Manufacturing engineering and technology - Schmid and Kalpakjian

Kalpakjian • Schmid
Manufacturing Engineering and Technology © 2001 Prentice-Hall Page 1-1
CHAPTER 1
The Structure of Metals

Chapter 1 Outline
Figure 1.1 An outline of the topics described in Chapter 1

Body-Centered Cubic Crystal Structure
Figure 1.2 The body-centered cubic (bcc) crystal structure: (a) hard-ball model; (b) unit cell; and (c) single
crystal with many unit cells. Source: W. G. Moffatt, et al., The Structure and Properties of Materials, Vol. 1,
John Wiley & Sons, 1976.

Face-Centered Cubic Crystal Structure
Figure 1.3 The face-centered cubic (fcc) crystal structure: (a) hard-ball model; (b) unit cell; and (c) single
crystal with many unit cells. Source: W. G. Moffatt, et al., The Structure and Properties of Materials, Vol. 1,
John Wiley & Sons, 1976.

Hexagonal Close-Packed Crystal Structure
Figure 1.4 The hexagonal close-
packed (hcp) crystal structure:
(a) unit cell; and (b) single
crystal with many unit cells.
Source: W. G. Moffatt, et al., The
Structure and Properties of
Materials, Vol. 1, John Wiley &
Sons, 1976.

Slip and Twinning
Figure 1.5 Permanent deformation (also
called plastic deformation) of a single
crystal subjected to a shear stress: (a)
structure before deformation; and (b)
permanent deformation by slip. The size
of the b/a ratio influences the magnitude
of the shear stress required to cause slip.
Figure 1.6 (a) Permanent deformation of a single
crystal under a tensile load. Note that the slip planes
tend to align themselves in the direction of the pulling
force. This behavior can be simulated using a deck of
cards with a rubber band around them. (b) Twinning
in a single crystal in tension.

Slip Lines and Slip Bands
Figure 1.7 Schematic illustration of slip lines
and slip bands in a single crystal (grain)
subjected to a shear stress. A slip band consists
of a number of slip planes. The crystal at the
center of the upper illustration is an individual
grain surrounded by other grains.

Edge and Screw Dislocations
Figure 1.8 Types of dislocations in a single crystal: (a) edge dislocation; and (b) screw dislocation.
Source: (a) After Guy and Hren, Elements of Physical Metallurgy, 1974. (b) L. Van Vlack, Materials for
Engineering, 4th ed., 1980.

Defects in a Single-Crystal Lattice
Figure 1.9 Schematic illustration of types of defects in a single-crystal lattice: self-
interstitial, vacancy, interstitial, and substitutional.

Movement of an Edge Dislocation
Figure 1.10 Movement of an edge dislocation across the crystal lattice under a shear stress.
Dislocations help explain why the actual strength of metals in much lower than that predicted by
theory.

Solidification
Figure 1.11 Schematic
illustration of the stages
during solidification of
molten metal; each small
square represents a unit cell.
(a) Nucleation of crystals at
random sites in the molten
metal; note that the
crystallographic orientation
of each site is different. (b)
and (c) Growth of crystals as
solidification continues. (d)
Solidified metal, showing
individual grains and grain
boundaries; note the different
angles at which neighboring
grains meet each other.
Source: W. Rosenhain.

Grain Sizes
TABLE 1.1
ASTM No. Grains/mm2
Grains/mm3
–3
–2
–1
0
1
2
3
4
5
6
7
8
9
10
11
12
1
2
4
8
16
32
64
128
256
512
1,024
2,048
4,096
8,200
16,400
32,800
0.7
2
5.6
16
45
128
360
1,020
2,900
8,200
23,000
65,000
185,000
520,000
1,500,000
4,200,000

Preferred Orientation
Figure 1.12 Plastic deformation of
idealized (equiaxed) grains in a
specimen subjected to compression
(such as occurs in the rolling or forging
of metals): (a) before deformation; and
(b) after deformation. Note hte
alignment of grain boundaries along a
horizontal direction; this effect is
known as preferred orientation.

Anisotropy
Figure 1.13 (a) Schematic illustration of a crack in sheet metal that has been subjected to bulging
(caused by, for example, pushing a steel ball against the sheet). Note the orientation of the crack with
respect to the rolling direction of the sheet; this sheet is anisotropic. (b) Aluminum sheet with a crack
(vertical dark line at the center) developed in a bulge test; the rolling direction of the sheet was vertical.
Source: J.S. Kallend, Illinois Institute of Technology.
(b)

Annealing
Figure 1.14 Schematic illustration of the
effects of recovery, recrystallization, and
grain growth on mechanical properties
and on the shape and size of grains. Note
the formation of small new grains during
recrystallization. Source: G. Sachs.

Homologous Temperature Ranges for Various
Processes
TABLE 1.2
Process T/Tm
Cold working
Warm working
Hot working
< 0.3
0.3 to 0.5
> 0.6

CHAPTER 2
Mechanical Behavior, Testing, and
Manufacturing Properties of Materials

Relative Mechanical Properties of Materials at
Room Temperature
TABLE 2.1
Strength Hardness Toughness Stiffness Strength/Density
Glass fibers
Graphite fibers
Kevlar fibers
Carbides
Molybdenum
Steels
Tantalum
Titanium
Copper
Reinforced
Reinforced
Thermoplastics
Lead
Diamond
Cubic boron nitride
Carbides
Hardened steels
Titanium
Cast irons
Copper
Thermosets
Magnesium
thermosets
thermoplastics
Lead
Rubbers
Ductile metals
Reinforced plastics
Thermoplastics
Wood
Thermosets
Ceramics
Glass
Ceramics
Reinforced
Thermoplastics
Tin
Thermoplastics
Diamond
Carbides
Tungsten
Steel
Copper
Titanium
Aluminum
Tantalum
plastics
Wood
Thermosets
Reinforced plastics
Titanium
Steel
Aluminum
Magnesium
Beryllium
Copper

Tensile-Test Specimen and Machine
(b)
Figure 2.1 (a) A standard tensile-test specimen before and after pulling, showing original and final
gage lengths. (b) A typical tensile-testing machine.

Stress-Strain Curve
Figure 2.2 A typical stress-
strain curve obtained from a
tension test, showing various
features.

Mechanical Properties of Various Materials at
Room Temperature
TABLE 2.2 Mechanical Properties of Various Materials at Room Temperature
Metals (Wrought) E (GPa) Y (MPa) UTS (MPa)
Elongation
in 50 mm
(%)
Aluminum and its alloys
Copper and its alloys
Lead and its alloys
Magnesium and its alloys
Molybdenum and its alloys
Nickel and its alloys
Steels
Titanium and its alloys
Tungsten and its alloys
69–79
105–150
14
41–45
330–360
180–214
190–200
80–130
350–400
35–550
76–1100
14
130–305
80–2070
105–1200
205–1725
344–1380
550–690
90–600
140–1310
20–55
240–380
90–2340
345–1450
415–1750
415–1450
620–760
45–4
65–3
50–9
21–5
40–30
60–5
65–2
25–7
0
Nonmetallic materials
Ceramics
Diamond
Glass and porcelain
Rubbers
Thermoplastics
Thermoplastics, reinforced
Thermosets
Boron fibers
Carbon fibers
Glass fibers
Kevlar fibers
70–1000
820–1050
70-80
0.01–0.1
1.4–3.4
2–50
3.5–17
380
275–415
73–85
62–117
—
—
—
—
—
—
—
—
—
—
—
140–2600
—
140
—
7–80
20–120
35–170
3500
2000–3000
3500–4600
2800
0
—
—
—
1000–5
10–1
0
0
0
0
0
Note: In the upper table the lowest values for E, Y, and UTS and the highest values for elongation are for pure metals.
Multiply gigapascals (GPa) by 145,000 to obtain pounds per square in. (psi), megapascals (MPa) by 145 to obtain psi.

Loading and Unloading of Tensile-Test
Specimen
Figure 2.3 Schematic illustration of the
loading and the unloading of a tensile- test
specimen. Note that, during unloading,
the curve follows a path parallel to the
original elastic slope.

Elongation versus % Area Reduction
Figure 2.4
Approximate
relationship
between elongation
and tensile
reduction of area
for various groups
of metals.

Construction of True Stress-True Strain Curve
Figure 2.5 (a) Load-elongation
curve in tension testing of a
stainless steel specimen. (b)
Engineering stress-engineering
strain curve, drawn from the data
in Fig. 2.5a. (c) True stress-true
strain curve, drawn from the data
in Fig. 2.5b. Note that this curve
has a positive slope, indicating
that the material is becoming
stronger as it is strained. (d) True
stress-true strain curve plotted on
log-log paper and based on the
corrected curve in Fig. 2.5c. The
correction is due to the triaxial
state of stress that exists in the
necked region of a specimen.

Typical Values for K and n at Room
Temperature
TABLE 2.3
K (MPa) n
Aluminum
1100–O
2024–T4
6061–O
6061–T6
7075–O
Brass
70–30, annealed
85–15, cold-rolled
Cobalt-base alloy, heat-treated
Copper, annealed
Steel
Low-C annealed
4135 annealed
4135 cold-rolled
4340 annealed
304 stainless, annealed
410 stainless, annealed
180
690
205
410
400
900
580
2070
315
530
1015
1100
640
1275
960
0.20
0.16
0.20
0.05
0.17
0.49
0.34
0.50
0.54
0.26
0.17
0.14
0.15
0.45
0.10

True Stress-True Strain Curves
Figure 2.6 True stress-true
strain curves in tension at
room temperature for
various metals. The curves
start at a finite level of
stress: The elastic regions
have too steep a slope to be
shown in this figure, and so
each curve starts at the
yield stress, Y, of the
material.

Temperature Effects on Stress-Strain Curves
Figure 2.7 Typical effects of temperature
on stress-strain curves. Note that
temperature affects the modulus of
elasticity, the yield stress, the ultimate
tensile strength, and the toughness (area
under the curve) of materials.

Typical Ranges of Strain and Deformation Rate in
Manufacturing Processes
TABLE 2.4
Process True strain
Deformation rate
(m/s)
Cold working
Forging, rolling
Wire and tube drawing
Explosive forming
Hot working and warm working
Forging, rolling
Extrusion
Machining
Sheet-metal forming
Superplastic forming
0.1–0.5
0.05–0.5
0.05–0.2
0.1–0.5
2–5
1–10
0.1–0.5
0.2–3
0.1–100
0.1–100
10–100
0.1–30
0.1–1
0.1–100
0.05–2
10
-4
-10
-2

Effect of Strain Rate on Ultimate Tensile
Strength
Figure 2.8 The effect of strain
rate on the ultimate tensile
strength for aluminum. Note
that, as the temperature
increases, the slopes of the
curves increase; thus, strength
becomes more and more
sensitive to strain rate as
temperature increases. Source:
J. H. Hollomon.

Disk and Torsion-Test Specimens
Figure 2.9 Disk test on a brittle
material, showing the direction
of loading and the fracture path.
Figure 2.10 Typical torsion-test
specimen; it is mounted between the
two heads of a testing machine and
twisted. Note the shear deformation of
an element in the reduced section of
the specimen.

Bending
Figure 2.11 Two bend-test
methods for brittle materials: (a)
three-point bending; (b) four-
point bending. The areas on the
beams represent the bending-
moment diagrams, described in
texts on mechanics of solids.
Note the region of constant
maximum bending moment in
(b); by contrast, the maximum
bending moment occurs only at
the center of the specimen in
(a).

Hardness Tests
Figure 2.12 General
characteristics of
hardness-testing
methods and formulas
for calculating
hardness. The quantity
P is the load applied.
Source: H. W. Hayden,
et al., The Structure
and Properties of
Materials, Vol. III
(John Wiley & Sons,
1965).

Brinell Testing
(c)
Figure 2.13 Indentation geometry in
Brinell testing; (a) annealed metal; (b)
work-hardened metal; (c) deformation of
mild steel under a spherical indenter.
Note that the depth of the permanently
deformed zone is about one order of
magnitude larger than the depth of
indentation. For a hardness test to be
valid, this zone should be fully
developed in the material. Source: M. C.
Shaw and C. T. Yang.

Hardness
Conversion
Chart
Figure 2.14 Chart
for converting
various hardness
scales. Note the
limited range of
most scales.
Because of the
many factors
involved, these
conversions are
approximate.

S-N Curves
Figure 2.15 Typical S-N
curves for two metals. Note
that, unlike steel, aluminum
does not have an endurance
limit.

Endurance Limit/Tensile Strength versus
Tensile Strength
Figure 2.16 Ratio of endurance limit to
tensile strength for various metals, as a
function of tensile strength. Because
aluminum does not have an endurance limit,
the correlation for aluminum are based on a
specific number of cycles, as is seen in Fig.
2.15.

Creep Curve
illustration of a typical creep
curve. The linear segment of
the curve (secondary) is used
in designing components for a
specific creep life.

Impact Test Specimens
Figure 2.18 Impact test
specimens: (a) Charpy;
(b) Izod.

Failures of Materials and Fractures in
Tension
Figure 2.19 Schematic illustration
of types of failures in materials: (a)
necking and fracture of ductile
materials; (b) Buckling of ductile
materials under a compressive load;
(c) fracture of brittle materials in
compression; (d) cracking on the
barreled surface of ductile materials
in compression.
Figure 2.20 Schematic illustration of the types of
fracture in tension: (a) brittle fracture in polycrystalline
metals; (b) shear fracture in ductile single crystals--see
also Fig. 1.6a; (c) ductile cup-and-cone fracture in
polycrystalline metals; (d) complete ductile fracture in
polycrystalline metals, with 100% reduction of area.

Ductile Fracture
Figure 2.21 Surface of ductile
fracture in low-carbon steel,
showing dimples. Fracture is
usually initiated at impurities,
inclusions, or preexisting voids
(microporosity) in the metal.
Source: K.-H. Habig and D.
Klaffke. Photo by BAM
Berlin/Germany.

Fracture of a Tensile-Test Specimen
Figure 2.22 Sequence of events in necking and fracture of a tensile-test specimen: (a) early stage of
necking; (b) small voids begin to form within the necked region; (c) voids coalesce, producing an
internal crack; (d) the rest of the cross-section begins to fail at the periphery, by shearing; (e) the final
fracture surfaces, known as cup- (top fracture surface) and cone- (bottom surface) fracture.

Deformation of Soft and Hard Inclusions
Figure 2.23 Schematic illustration of the deformation of soft and hard inclusions and of their effect on void
formation in plastic deformation. Note that, because they do not comply with the overall deformation of the
ductile matrix, hard inclusions can cause internal voids.

Transition Temperature
illustration of transition
temperature in metals.

Brittle Fracture Surface
Figure 2.25 Fracture
surface of steel that has
failed in a brittle manner.
The fracture path is
transgranular (through the
grains). Magnification:
200X. Source: Courtesy
of B. J. Schulze and S. L.
Meiley and Packer
Engineering Associates,
Inc.

Intergranular Fracture
Figure 2.26 Intergranular
fracture, at two different
magnifications. Grains
and grain boundaries are
clearly visible in this
micrograph. Te fracture
path is along the grain
boundaries.
Magnification: left, 100X;
right, 500X. Source:
Courtesy of B. J. Schulze
and S. L. Meiley and
Packer Engineering
Associates, Inc.

Fatigue-Fracture Surface
Figure 2.27 Typical
fatigue-fracture surface on
metals, showing beach
marks. Magnification:
left, 500X; right, 1000X.
Source: Courtesy of B. J.
Schulze and S. L. Meiley
and Packer Engineering
Associates, Inc.

Reduction in Fatigue Strength
Figure 2.28 Reductions in the
fatigue strength of cast steels
subjected to various surface-
finishing operations. Note that the
reduction becomes greater as the
surface roughness and the strength
of the steel increase. Source: M.
R. Mitchell.

Residual Stresses
Figure 2.29 Residual stresses developed in bending a beam having a rectangular cross-section. Note that the
horizontal forces and moments caused by residual stresses in the beam must be balanced internally. Because of
nonuniform deformation during metalworking operations, most parts develop residual stresses.

Distortion of Parts with Residual Stresses
Figure 2.30 Distortion of parts, with residual stresses, after cutting or slitting: (a) flat
sheet or plate; (b) solid round rod; (c) think-walled tubing or pipe.

CHAPTER 3
Physical Properties of Materials

Physical Properties of Selected Materials at
Room Temperature
TABLE 3.1 Physical Properties of Selected Materials at Room Temperature
Metal Density
(kg/m
3
)
Melting Point
(°C)
Specific heat
(J/kg K)
Thermal conductivity
(W/m K)
Aluminum
Aluminum alloys
Beryllium
Columbium (niobium)
Copper
Copper alloys
Iron
Steels
Lead
Lead alloys
Magnesium
Magnesium alloys
Molybdenum alloys
Nickel
Nickel alloys
Tantalum alloys
Titanium
Titanium alloys
Tungsten
Zinc
Zinc alloys
2700
2630–2820
1854
8580
8970
7470–8940
7860
6920–9130
11,350
8850–11,350
1745
1770–1780
10,210
8910
7750–8850
16,600
4510
4430–4700
19,290
7140
6640–7200
660
476–654
1278
2468
1082
885–1260
1537
1371–1532
327
182–326
650
610–621
2610
1453
1110–1454
2996
1668
1549–1649
3410
419
386–525
900
880–920
1884
272
385
377–435
460
448–502
130
126–188
1025
1046
276
440
381–544
142
519
502–544
138
385
402
222
121–239
146
52
393
29–234
74
15–52
35
24–46
154
75–138
142
92
12–63
54
17
8–12
166
113
105–113
Nonmetallic
Ceramics
Glasses
Graphite
Plastics
Wood
2300–5500
2400–2700
1900–2200
900–2000
400–700
—
580–1540
—
110–330
—
750–950
500–850
840
1000–2000
2400–2800
10–17
0.6–1.7
5–10
0.1–0.4
0.1–0.4

Physical Properties of Material
TABLE 3.2 Physical Properties of Materials, in Descending Order
Density Melting point Specific heat Thermal
conductivity
Thermal
expansion
Electrical
conductivity
Platinum
Gold
Tungsten
Tantalum
Lead
Silver
Molybdenum
Copper
Steel
Titanium
Aluminum
Beryllium
Glass
Magnesium
Plastics
Tungsten
Tantalum
Molybdenum
Columbium
Titanium
Iron
Beryllium
Copper
Gold
Silver
Aluminum
Magnesium
Lead
Tin
Plastics
Wood
Beryllium
Porcelain
Aluminum
Graphite
Glass
Titanium
Iron
Copper
Molybdenum
Tungsten
Lead
Silver
Copper
Gold
Aluminum
Magnesium
Graphite
Tungsten
Beryllium
Zinc
Steel
Tantalum
Ceramics
Titanium
Glass
Plastics
Plastics
Lead
Tin
Magnesium
Aluminum
Copper
Steel
Gold
Ceramics
Glass
Tungsten
Silver
Copper
Gold
Aluminum
Magnesium
Tungsten
Beryllium
Steel
Tin
Graphite
Ceramics
Glass
Plastics
Quartz

Specific
Strength and
Specific
Stiffness
Figure 3.1 Specific
strength (tensile
strength/density) and
specific stiffness (elastic
modulus/density) for
various materials at
room temperature. (See
also Chapter 9.) Source:
M.J. Salkind.

Specific Strength versus Temperature
Figure 3.2 Specific strength (tensile strength/density) for a variety of materials as a
function of temperature. Note the useful temperature range for these materials and the
high values for composite materials.

CHAPTER 4
Metal Alloys: Their Structure and
Strengthening by Heat Treatment

Induction-Hardened Surface
Figure 4.1 Cross-section of
gear teeth showing
induction-hardened
surfaces. Source: TOCCO
Div., Park-Ohio Industries,
Inc.

Chapter 4 Outline
Figure 4.2 Outline of topics described in Chapter 4.

Two-Phase System
Figure 4.3 (a) Schematic illustration of grains, grain boundaries, and particles dispersed throughout
the structure of a two-phase system, such as a lead-copper alloy. The grains represent lead in solid
solution in copper, and the particles are lead as a second phase. (b) Schematic illustration of a two-
phase system consisting of two sets of grains: dark, and light. The dark and the light grains have
separate compositions and properties.

Cooling Curve
Figure 4.4 Cooling curve for
the solidification of pure
metals. Note that freezing takes
place at a constant temperature;
during freezing the latent heat
of solidification is given off.

Nickel-Copper Alloy Phase Diagram
Figure 4.5 Phase
diagram for nickel-
copper alloy system
obtained at a slow
rate of solidification.
Note that pure nickel
and pure copper each
has one freezing or
melting temperature.
The top circle on the
right depicts the
nucleation of
crystals. The second
circle shows the
formation of
dendrites (see
Section 10.2). The
bottom circle shows
the solidified alloy,
with grain
boundaries.

Mechanical Properties of Copper-Nickel and
Copper-Zinc Alloys
Figure 4.6 Mechanical
properties of copper-nickel
and copper-zinc alloys as a
function of their
composition. The curves
for zinc are short, because
zinc has a maximum solid
solubility of 40% in copper.
Source: L. H. Van Vlack;
Materials for Engineering.
Addison-Wesley
Publishing Co., Inc., 1982.

Lead-Tin Phase Diagram
Figure 4.7 The
lead-tin phase
diagram. Note that
the composition of
the eutectic point for
this alloy is 61.9%
Sn-38.1% Pb. A
composition either
lower or higher than
this ratio will have a
higher liquidus
temperature.

Iron-Iron Carbide Phase Diagram
Figure 4.8 The iron-iron
carbide phase diagram.
Because of the
importance of steel as an
engineering material, this
diagram is one of the
most important of all
phase diagrams.

Austenite, Ferrite, and Martensite
Figure 4.9 The unit cells for (a) austenite, (b) ferrite, and (c) martensite. The effect of percentage of
carbon (by weight) on the lattice dimensions for martensite is shown in (d). Note the interstitial position
of the carbon atoms (see Fig. 1.9). Note, also, the increase in dimension c with increasing carbon content;
this effect causes the unit cell of martensite to be in the shape of a rectangular prism.

Iron-Carbon Alloy Above and Below Eutectoid
Temperature
of the microstructures for an iron-
carbon alloy of eutectoid
composition (0.77% carbon), above
and below the eutectoid temperature
of 727 °C (1341 °F).

Pearlite Microstructure
Figure 4.11 Microstructure of
pearlite in 1080 steel, formed
from austenite of eutectoid
composition. In this lamellar
structure, the lighter regions are
ferrite, and the darker regions are
carbide. Magnification: 2500X.
Source: Courtesy of USX
Corporation.

Extended Iron-Carbon Phase Diagram
Figure 4.12 Phase diagram for the iron-carbon system with graphite (instead
of cementite) as the stable phase. Note that this figure is an extended version
of Fig. 4.8.

Microstructures for Cast Irons
(a) (b) (c)
Figure 4.13 Microstructure for cast irons. Magnification: 100X. (a) Ferritic gray iron with graphite flakes. (b)
Ferritic Ductile iron (nodular iron), with graphite in nodular form. (c) Ferritic malleable iron; this cast iron
solidified as white cast iron, with the carbon present as cementite, and was heat treated to graphitize the carbon.
Source: ASM International.

Austenite to
Pearlite
Transformation
Figure 4.14 (a) Austenite-
to-pearlite transformation
of iron-carbon alloy as a
functionof time and
temperature. (b)
Isothermal transformation
diagram obtained from (a)
for a transformation
temperature of 675 °C
(1247 °F). (continued)

Austenite to Pearlite Transformation (cont.)
Figure 4.14 (c) Microstructures
obtained for a eutectoid iron-carbon
alloy as a function of cooling rate.

Hardness and Toughness of Annealed Steels
Figure 4.15 (a) and (b) Hardness and (c) toughness for annealed plain-carbon steels, as a function of carbide
shape. Carbides in the pearlite are lamellar. Fine pearlite is obtained by increasing the cooling rate. The
spheroidite structure has spherelike carbide particles. Note htat the percentage of pearlite begins to decrease
after 0.77% carbon. Source: L. H. Van Vlack; Materials for Engineering. Addison-Wesley Publishing Co.,
Inc., 1982.

Mechanical Properties of Annealed Steels
Figure 4.16 Mechanical properties of annealed steels, as a function of composition and microstructure. Note
(in (a)) the increase in hardness and strength and (in (b)) the decrease in ductility and toughness, with
increasing amounts of pearlite and iron carbide. Source: L. H. Van Vlack; Materials for Engineering.
Addison-Wesley Publishing Co., Inc., 1982.

Eutectoid Steel Microstructure
Figure 4.17 Microstructure
of eutectoid steel.
Spheroidite is formed by
tempering the steel at 700 °C
(1292 °F). Magnification:
1000X. Source: Courtesy of
USX Corporation.

Martensite
(b)
Figure 4.18 (a) Hardness of martensite, as a function of carbon content. (b) Micrograph of martensite
containing 0.8% carbon. The gray platelike regions are martensite; they have the same composition as the
original austenite (white regions). Magnification: 1000X. Source: Courtesy of USX Corporation.

Hardness of Tempered Martensite
Figure 4.19 Hardness
of tempered
martensite, as a
function of tempering
time, for 1080 steel
quenched to 65 HRC.
Hardness decreases
because the carbide
particles coalesce and
grow in size, thereby
increasing the
interparticle distance
of the softer ferrite.

End-Quench
Hardenability
Test
Figure 4.20 (a)
End-quench test
and cooling rate.
(b) Hardenability
curves for five
different steels, as
obtained from the
end-quench test.
Small variations in
composition can
change the shape of
these curves. Each
curve is actually a
band, and its exact
determination is
important in the
heat treatment of
metals, for better
control of
properties. Source:
L. H. Van Vlack;
Materials for
Engineering.
Addison-Wesley
Publishing Co.,
Inc., 1982.

Aluminum-Copper Phase Diagram
Figure 4.21 (a) Phase diagram for the aluminum-copper alloy system. (b) Various micro-
structures obtained during the age-hardening process. Source: L. H. Van Vlack; Materials for
Engineering. Addison-Wesley Publishing Co., Inc., 1982.

Age Hardening
Figure 4.22 The effect of aging
time and temperature on the yield
stress of 2014-T4 aluminum alloy.
Note that, for each temperature,
there is an optimal aging time for
maximum strength.

Outline of Heat Treatment Processes for
Surface Hardening
TABLE 4.1
Process Metals hardened Element added to
surface
Procedure General Characteristics Typical applications
Carburizing Low-carbon steel
(0.2% C), alloy
steels (0.08–0.2%
C)
C Heat steel at 870–950 °C (1600–1750
°F) in an atmosphere of carbonaceous
gases (gas carburizing) or carbon-
containing solids
(pack carburizing). Then quench.
A hard, high-carbon surface is
produced. Hardness 55 to 65
HRC. Case depth < 0.5–1.5 mm
( < 0.020 to 0.060 in.). Some
distortion of part during heat
treatment.
Gears, cams, shafts,
bearings, piston pins,
sprockets, clutch plates
Carbonitriding Low-carbon steel C and N Heat steel at 700–800 °C (1300–1600
°F) in an atmosphere of carbonaceous
gas and ammonia. Then quench in oil.
Surface hardness 55 to 62 HRC.
Case depth 0.07 to 0.5 mm
(0.003 to 0.020 in.). Less
distortion than in
carburizing.
Bolts, nuts, gears
Cyaniding Low-carbon steel
(0.2% C), alloy
steels (0.08–0.2%
C)
C and N Heat steel at 760–845 °C (1400–1550
°F) in a molten bath of solutions of
cyanide (e.g., 30% sodium cyanide) and
other salts.
Surface hardness up to 65 HRC.
Case depth 0.025 to 0.25 mm
(0.001 to 0.010 in.). Some
distortion.
Bolts, nuts, screws, small
gears
Nitriding Steels (1% Al,
1.5% Cr, 0.3%
Mo), alloy steels
(Cr, Mo), stainless
steels, high-speed
tool steels
N Heat steel at 500–600 °C (925–1100 °F)
in an atmosphere of ammonia gas or
mixtures of molten cyanide salts. No
further treatment.
Surface hardness up to 1100
HV. Case depth 0.1 to 0.6 mm
(0.005 to 0.030 in.) and 0.02 to
0.07 mm (0.001
to 0.003 in.) for high speed
steel.
Gears, shafts, sprockets,
valves, cutters, boring
bars, fuel-injection pump
parts
Boronizing Steels B Part is heated using boron-containing
gas or solid in contact with part.
Extremely hard and wear
resistant surface. Case depth
0.025– 0.075 mm (0.001–
0.003 in.).
Tool and die steels
Flame hardening Medium-carbon
steels, cast irons
None Surface is heated with an oxyacetylene
torch, then quenched with water spray or
other quenching methods.
Surface hardness 50 to 60 HRC.
Case depth 0.7 to 6 mm (0.030
to 0.25 in.). Little distortion.
Gear and sprocket teeth,
axles, crankshafts, piston
rods, lathe beds and
centers
Induction
hardening
Same as above None Metal part is placed in copper induction
coils and is heated by high frequency
current, then quenched.
Same as above Same as above

Heat Treatment Processes
Figure 4.23 Heat-treating temperature ranges for
plain-carbon steels, as indicated on the iron-iron
carbide phase diagram. Source: ASM
International.
Figure 4.24 Hardness of steels in the quenched and
normalized conditions, as a function of carbon content.

Properties of Oil-Quenched Steel
Figure 4.25 Mechanical properties of
oil-quenched 4340 steel, as a function
of tempering temperature. Source:
Courtesy of LTV Steel Company

Induction Heating
Figure 4.26 Types of coils used in induction heating of various surfaces of parts.

CHAPTER 5
Ferrous Metals and Alloys: Production,
General Properties, and Applications

Blast Furnace
Figure 5.1
Schematic
illustration of a
blast furnace.
Source: Courtesy
of American Iron
and Steel Institute.

Electric Furnaces
Figure 5.2 Schematic illustration of types of electric furnaces: (a) direct arc, (b) indirect arc, and (c) induction.

Basic-Oxygen Process
illustrations showing
(a) charging, (b)
melting, and (c)
pouring of molten iron
in a basic-oxygen
process. Source:
Inland Steel Company

Continuous
Casting
Figure 5.4 The
continuous-casting
process for steel.
Typically, the solidified
metal descends at a speed
of 25 mm/s (1 in./s).
Note that the platform is
about 20 m (65 ft) above
ground level. Source:
Metalcaster's Reference
and Guide, American
Foundrymen's Society.

Typical Selection of Carbon and Alloy Steels for
Various Applications
TABLE 5.1
Product Steel Product Steel
Aircraft forgings,
tubing, fittings
Automobile bodies
Axles
Ball bearings and races
Bolts
Camshafts
Chains (transmission)
Coil springs
Connecting rods
Crankshafts (forged)
4140, 8740
1010
1040, 4140
52100
1035, 4042, 4815
1020, 1040
3135, 3140
4063
1040, 3141, 4340
1045, 1145, 3135, 3140
Differential gears
Gears (car and truck)
Landing gear
Lock washers
Nuts
Railroad rails and wheels
Springs (coil)
Springs (leaf)
Tubing
Wire
Wire (music)
4023
4027, 4032
4140, 4340, 8740
1060
3130
1080
1095, 4063, 6150
1085, 4063, 9260, 6150
1040
1045, 1055
1085

Mechanical Properties of Selected Carbon and
Alloy Steels in Various Conditions
TABLE 5.2 Typical Mechanical Properties of Selected Carbon and Alloy Steels in the Hot-Rolled,
Normalized, and Annealed Condition
AISI Condition Ultimate
tensile
strength
(MPa)
Yield
Strength
(MPa)
Elongation in
50 mm (%)
Reduction of
area (%)
Hardness
(HB)
1020
1080
3140
4340
8620
As-rolled
Normalized
Annealed
As-rolled
Normalized
Annealed
Normalized
Annealed
Normalized
Annealed
Normalized
Annealed
448
441
393
1010
965
615
891
689
1279
744
632
536
346
330
294
586
524
375
599
422
861
472
385
357
36
35
36
12
11
24
19
24
12
22
26
31
59
67
66
17
20
45
57
50
36
49
59
62
143
131
111
293
293
174
262
197
363
217
183
149

AISI Designation for High-Strength Sheet
Steel
TABLE 5.3
Yield Strength Chemical
Composition
Deoxidation
Practice
psi x 10
3
MPa
35
40
45
50
60
70
80
100
120
140
240
275
310
350
415
485
550
690
830
970
S = structural alloy
X = low alloy
W = weathering
D = dual phase
F = killed plus sulfide inclusion control
K = killed
O = nonkilled

Room-Temperature Mechanical Properties and
Applications of Annealed Stainless Steels
TABLE 5.4 Room-Temperature Mechanical Properties and Typical Applications of Selected Annealed
Stainless Steels
AISI
(UNS)
Ultimate
tensile
strength
(MPa)
Yield
strength
(MPa)
Elongation
in 50 mm
(%) Characteristics and typical applications
303
(S30300)
550–620 240–260 53–50 Screw machine products, shafts, valves, bolts,
bushings, and nuts; aircraft fittings; bolts; nuts;
rivets; screws; studs.
304
(S30400)
565–620 240–290 60–55 Chemical and food processing equipment,
brewing equipment, cryogenic vessels, gutters,
downspouts, and flashings.
316
(S31600)
550–590 210–290 60–55 High corrosion resistance and high creep strength.
Chemical and pulp handling equipment,
photographic equipment, brandy vats, fertilizer
parts, ketchup cooking kettles, and yeast tubs.
410
(S41000)
480–520 240–310 35–25 Machine parts, pump shafts, bolts, bushings, coal
chutes, cutlery, tackle, hardware, jet engine parts,
mining machinery, rifle barrels, screws, and
valves.
416
(S41600)
480–520 275 30–20 Aircraft fittings, bolts, nuts, fire extinguisher
inserts, rivets, and screws.

Basic Types of Tool and Die Steels
TABLE 5.5
Type AISI
High speed
Hot work
Cold work
Shock resisting
Mold steels
Special purpose
Water hardening
M (molybdenum base)
T (tungsten base)
H1 to H19 (chromium base)
H20 to H39 (tungsten base)
H40 to H59 (molybdenum base)
D (high carbon, high chromium)
A (medium alloy, air hardening)
O (oil hardening)
S
P1 to P19 (low carbon)
P20 to P39 (others)
L (low alloy)
F (carbon-tungsten)
W

Processing and Service Characteristics of
Common Tool and Die Steels
TABLE 5.6 Processing and Service Characteristics of Common Tool and Die Steels
AISI
designation
Resistance to
decarburization
Resistance to
cracking
Approximate
hardness
(HRC) Machinability Toughness
Resistance to
softening
Resistance to
wear
M2 Medium Medium 60–65 Medium Low Very high Very high
T1 High High 60–65 Medium Low Very high Very high
T5 Low Medium 60–65 Medium Low Highest Very high
H11, 12, 13 Medium Highest 38–55 Medium to high Very high High Medium
A2 Medium Highest 57–62 Medium Medium High High
A9 Medium Highest 35–56 Medium High High Medium to
high
D2 Medium Highest 54–61 Low Low High High to very
high
D3 Medium High 54–61 Low Low High Very high
H21 Medium High 36–54 Medium High High Medium to
high
H26 Medium High 43–58 Medium Medium Very high High
P20 High High 28–37 Medium to high High Low Low to
medium
P21 High Highest 30–40 Medium Medium Medium Medium
W1, W2 Highest Medium 50–64 Highest High Low Low to
medium
Source: Adapted from Tool Steels, American Iron and Steel Institute, 1978.

CHAPTER 6
Nonferrous Metals and Alloys:
Production, General Properties, and
Applications

Approximate Cost per Unit Volume for Wrought
Metals and Plastics Relative to Carbon Steel
TABLE 6.1 Approximate Cost per Unit Volume for Wrought Metals and Plastics Relative to
Cost of Carbon Steel
Gold
Silver
Molybdenum alloys
Nickel
Titanium alloys
Copper alloys
Zinc alloys
Stainless steels
60,000
600
200–250
35
20–40
5–6
1.5–3.5
2–9
Magnesium alloys
Aluminum alloys
High-strength low-alloy steels
Gray cast iron
Carbon steel
Nylons, acetals, and silicon rubber
*
Other plastics and elastomers
*
2–4
2–3
1.4
1.2
1
1.1–2
0.2–1
*As molding compounds.
Note: Costs vary significantly with quantity of purchase, supply and demand, size and shape, and various other factors.

General Characteristics of Nonferrous Metals
and Alloys
TABLE 6.2
Material Characteristics
Nonferrous alloys More expensive than steels and plastics; wide range of mechanical, physical, and
electrical properties; good corrosion resistance; high-temperature applications.
Aluminum High strength-to-weight ratio; high thermal and electrical conductivity; good
corrosion resistance; good manufacturing properties.
Magnesium Lightest metal; good strength-to-weight ratio.
Copper High electrical and thermal conductivity; good corrosion resistance; good
manufacturing properties.
Superalloys Good strength and resistance to corrosion at elevated temperatures; can be iron-,
cobalt-, and nickel-base.
Titanium Highest strength-to-weight ratio of all metals; good strength and corrosion
resistance at high temperatures.
Refractory metals Molybdenum, niobium (columbium), tungsten, and tantalum; high strength at
elevated temperatures.
Precious metals Gold, silver, and platinum; generally good corrosion resistance.

Example of Alloy Usage
Figure 6.1 Cross-
section of a jet
engine (PW2037)
showing various
components and the
alloys used in
manufacturing
them. Source:
Courtesy of United
Aircraft Pratt &
Whitney.

Properties of Selected Aluminum Alloys at
Room Temperature
TABLE 6.3
Alloy (UNS) Temper
Ultimate tensile
strength (MPa)
Yield strength
(MPa)
Elongation
in 50 mm
(%)
1100 (A91100)
1100
2024 (A92024)
2024
3003 (A93003)
3003
5052 (A95052)
5052
6061 (A96061)
6061
7075 (A97075)
7075
O
H14
O
T4
O
H14
O
H34
O
T6
O
T6
90
125
190
470
110
150
190
260
125
310
230
570
35
120
75
325
40
145
90
215
55
275
105
500
35–45
9–20
20–22
19–20
30–40
8–16
25–30
10–14
25–30
12–17
16–17
11

Manufacturing Properties and Applications of
Selected Wrought Aluminum Alloys
TABLE 6.4
Characteristics*
Alloy
Corrosion
resistance Machinability Weldability Typical applications
1100 A C–D A Sheet metal work, spun hollow ware, tin
stock
2024 C B–C B–C Truck wheels, screw machine products,
aircraft structures
3003 A C–D A Cooking utensils, chemical equipment,
pressure vessels, sheet metal work,
builders’ hardware, storage tanks
5052 A C–D A Sheet metal work, hydraulic tubes, and
appliances; bus, truck and marine uses
6061 B C–D A Heavy-duty structures where corrosion
resistance is needed, truck and marine
structures, railroad cars, furniture,
pipelines, bridge rail-ings, hydraulic
tubing
7075 C B–D D Aircraft and other structures, keys,
hydraulic fittings
* A, excellent; D, poor.

All-Aluminum Automobile
Figure 6.2 (a) The Audi A8
automobile which has an all-
aluminum body structure. (b) The
aluminum body structure, showing
various components made by
extrusion, sheet forming, and casting
processes. Source: Courtesy of
ALCOA, Inc.

Properties and Typical Forms of Selected
Wrought Magnesium Alloys
TABLE 6.5
Composition (%)
Ultimate
tensile Yield Elongation
Alloy Al Zn Mn Zr Condition
strength
(MPa)
strength
(MPa)
in 50 mm
(%) Typical forms
AZ31 B 3.0 1.0 0.2 F 260 200 15 Extrusions
H24 290 220 15 Sheet and plates
AZ80A 8.5 0.5 0.2 T5 380 275 7 Extrusions and
forgings
HK31A 3Th 0.7 H24 255 200 8 Sheet and plates
ZK60A 5.7 0.55 T5 365 300 11 Extrusions and
forgings

Properties and Typical Applications of Selected
Wrought Copper and Brasses
TABLE 6.6
Type and UNS
number
Nominal
composition (%)
Ultimate
tensile
strength
(MPa)
Yield
strength
(MPa)
Elongation
in 50 mm
(%) Typical applications
Electrolytic tough pitch
copper (C11000)
99.90 Cu, 0.04 O 220–450 70–365 55–4 Downspouts, gutters, roofing,
gaskets, auto radiators, busbars,
nails, printing rolls, rivets
Red brass, 85%
(C23000)
85.0 Cu, 15.0 Zn 270–725 70–435 55–3 Weather-stripping, conduits,
sockets, fas-teners, fire
extinguishers, condenser and heat
exchanger tubing
Cartridge brass, 70%
(C26000)
70.0 Cu, 30.0 Zn 300–900 75–450 66–3 Radiator cores and tanks, flashlight
shells, lamp fixtures, fasteners,
locks, hinges, ammunition
components, plumbing accessories
Free-cutting brass
(C36000)
61.5 Cu, 3.0 Pb,
35.5 Zn
340–470 125–310 53–18 Gears, pinions, automatic high-
speed screw machine parts
Naval brass
(C46400 to C46700)
60.0 Cu, 39.25 Zn,
0.75 Sn
380–610 170–455 50–17 Aircraft turnbuckle barrels, balls,
bolts, marine hardware, propeller
shafts, rivets, valve stems,
condenser plates

Wrought Bronzes
TABLE 6.7
Type and UNS number
Nominal
composition (%)
Ultimate
tensile
strength
(MPa)
Yield
strength
(MPa)
Elongation
in 50 mm
Architectural bronze
(C38500)
57.0 Cu, 3.0 Pb,
40.0 Zn
415 (As
extruded)
140 30 Architectural extrusions, store
fronts, thresholds, trim, butts,
hinges
Phosphor bronze, 5% A
(C51000)
95.0 Cu, 5.0 Sn,
trace P
325–960 130–550 64–2 Bellows, clutch disks, cotter pins,
diaphragms, fasteners, wire
brushes, chemical hardware, textile
machinery
Free-cutting phosphor
bronze (C54400)
88.0 Cu, 4.0 Pb,
4.0 Zn, 4.0 Sn
300–520 130–435 50–15 Bearings, bushings, gears, pinions,
shafts, thrust washers, valve parts
Low silicon bronze, B
(C65100)
98.5 Cu, 1.5 Si 275–655 100–475 55–11 Hydraulic pressure lines, bolts,
marine hardware, electrical
conduits, heat exchanger tubing
Nickel silver, 65–10
(C74500)
65.0 Cu, 25.0 Zn,
10.0 Ni
340–900 125–525 50–1 Rivets, screws, slide fasteners,
hollow ware, nameplates

Nickel Alloys
TABLE 6.8 Properties and Typical Applications of Selected Nickel Alloys (All are Trade Names)
Type and UNS number
Nominal
composition (%)
Ultimate
tensile
strength
(MPa)
Yield
strength
(MPa)
Elongation
in 50 mm
Nickel 200 (annealed) None 380–550 100–275 60–40 Chemical and food processing
industry, aerospace equipment,
electronic parts
Duranickel 301 4.4 Al, 0.6 Ti 1300 900 28 Springs, plastics extrusion equipment,
(age hardened) molds for glass,
diaphragms
Monel R-405 (hot
rolled)
30 Cu 525 230 35 Screw-machine products, water meter
parts
Monel K-500 29 Cu, 3 Al 1050 750 30 Pump shafts, valve stems, springs (age
hardened)
Inconel 600 (annealed) 15 Cr, 8 Fe 640 210 48 Gas turbine parts, heat-treating
equipment, electronic parts, nuclear
reactors
Hastelloy C-4 (solution-
treated and quenched)
16 Cr, 15 Mo 785 400 54 High temperature stability, resistance
to stress-corrosion cracking

Nickel-Base Superalloys at 870 °C
TABLE 6.9 Properties and Typical Applications of Selected Nickel-BaseSuperalloys at 870 °C
(1600 °F) (All are Trade Names)
Alloy Condition
Ultimate
tensile
strength
(MPa)
Yield
strength
(MPa)
Elongation
in 50 mm
Astroloy Wrought 770 690 25 Forgings for high temperature
Hastelloy X Wrought 255 180 50 Jet engine sheet parts
IN-100 Cast 885 695 6 Jet engine blades and wheels
IN-102 Wrought 215 200 110 Superheater and jet engine parts
Inconel 625 Wrought 285 275 125 Aircraft engines and structures,
chemical processing equipment
lnconel 718 Wrought 340 330 88 Jet engine and rocket parts
MAR-M 200 Cast 840 760 4 Jet engine blades
MAR-M 432 Cast 730 605 8 Integrally cast turbine wheels
René 41 Wrought 620 550 19 Jet engine parts
Udimet 700 Wrought 690 635 27 Jet engine parts
Waspaloy Wrought 525 515 35 Jet engine parts

Wrought Titanium Alloys
TABLE 6.10 Properties and Typical Applications of Selected Wrought Titanium Alloys at Various
Temperatures
Nominal
compos-
ition
(%) UNS Condition
Ultimate
tensile
strength
(MPa)
Yield
strength
(MPa)
Elonga-
tion (%)
Reduc-
tion of
area (%)
Temp.
(°C)
Ultimate
tensile
strength
(MPa)
Yield
strength
(MPa)
Elonga-
tion in
50 mm
(%)
Reduc-
tion of
area Typical Applications
99.5 Ti R50250 Annealed 330 240 30 55 300 150 95 32 80 Airframes; chemical,
desalination, and
marine parts; plate
type heat exchangers
5 Al,
2.5 Sn
R54520 Annealed 860 810 16 40 300 565 450 18 45 Aircraft engine
compressor blades and
ducting; steam turbine
blades
6 Al,
4V
R56400 Annealed 1000 925 14 30 300 725 650 14 35 Rocket motor cases;
blades and disks for
aircraft turbines and
compressors;
structural forgings and
fasteners; orthopedic
implants
425 670 570 18 40
550 530 430 35 50
Solution +
age
1175 1100 10 20 300 980 900 10 28
12 35
22 45
13 V,
11 Cr,
3 Al
R58010 Solution +
age
1275 1210 8 — 425 1100 830 12 — High strength
fasteners; aerospace
components;
honeycomb panels

CHAPTER 7
Polymers: Structure, General Properties
and Applications

Range of Mechanical Properties for Various
Engineering Plastics
TABLE 7.1
Material UTS (MPa) E (GPa)
Elongation
(%)
Poisson’s
ratio (ν)
ABS
ABS, reinforced
Acetal
Acetal, reinforced
Acrylic
Cellulosic
Epoxy
Epoxy, reinforced
Fluorocarbon
Nylon
Nylon, reinforced
Phenolic
Polycarbonate
Polycarbonate, reinforced
Polyester
Polyester, reinforced
Polyethylene
Polypropylene
Polypropylene, reinforced
Polystyrene
Polyvinyl chloride
28–55
100
55–70
135
40–75
10–48
35–140
70–1400
7–48
55–83
70–210
28–70
55–70
110
55
110–160
7–40
20–35
40–100
14–83
7–55
1.4–2.8
7.5
1.4–3.5
10
1.4–3.5
0.4–1.4
3.5–17
21–52
0.7–2
1.4–2.8
2–10
2.8–21
2.5–3
6
2
8.3–12
0.1–1.4
0.7–1.2
3.5–6
1.4–4
0.014–4
75–5
—
75–25
—
50–5
100–5
10–1
4–2
300–100
200–60
10–1
2–0
125–10
6–4
300–5
3–1
1000–15
500–10
4–2
60–1
450–40
—
0.35
—
0.35–0.40
—
—
—
—
0.46–0.48
0.32–0.40
—
—
0.38
—
0.38
—
0.46
—
—
0.35
—

Chapter 7 Outline
Figure 7.1 Outline of the topics described in Chapter 7

Structure of
Polymer
Molecules
Figure 7.2 Basic structure of polymer molecules: (a) ethylene molecule; (b)
polyethylene, a linear chain of many ethylene molecules; © molecular structure
of various polymers. These are examples of the basic building blocks for
plastics

Molecular Weight and Degree of Polymerization
Figure 7.3 Effect of molecular weight
and degree of polymerization on the
strength and viscosity of polymers.

Polymer Chains
illustration of polymer chains.
(a) Linear structure--
thermoplastics such as
acrylics, nylons, polyethylene,
and polyvinyl chloride have
linear structures. (b) Branched
structure, such as in
polyethylene. (c) Cross-linked
structure--many rubbers or
elastomers have this structure,
and the vulcanization of rubber
produces this structure. (d)
Network structure, which is
basically highly cross-linked--
examples are thermosetting
plastics, such as epoxies and
phenolics.

Polymer Behavior
Figure 7.5 Behavior of polymers as a function of temperature and (a) degree of crystallinity and (b)
cross-linking. The combined elastic and viscous behavior of polymers is known as viscoelasticity.

Crystallinity
Figure 7.6 Amorphous
and crystalline regions in
a polymer. The crystalline
region (crystallite) has an
orderly arrangement of
molecules. The higher the
crystallinity, the harder,
stiffer, and less ductile the
polymer.

Specific Volume as a Function of Temperature
Figure 7.7 Specific volume of polymers
as a function of temperature. Amorphous
polymers, such as acrylic and
polycarbonate, have a glass-transition
temperature, Tg, but do not have a specific
melting point, Tm. Partly crystalline
polymers, such as polyethylene and
nylons, contract sharply while passing
through their melting temperatures during
cooling.

Glass-Transition and Melting Temperatures of
Some Polymers
TABLE 7.2
Material Tg (°C) Tm (°C)
Nylon 6,6
Polycarbonate
Polyester
Polyethylene
High density
Low density
Polymethylmethacrylate
Polypropylene
Polystyrene
Polytetrafluoroethylene
Polyvinyl chloride
Rubber
57
150
73
–90
–110
105
–14
100
–90
87
–73
265
265
265
137
115
—
176
239
327
212
—

Behavior of Plastics
Figure 7.8 General terminology describing
the behavior of three types of plastics. PTFE
(polytetrafluoroethylene) has Teflon as its
trade name. Source: R. L. E. Brown.

Temperature Effects
Figure 7.9 Effect of temperature on the stress-strain
curve for cellulose acetate, a thermoplastic. Note the
large drop in strength and the large increase in
ductility with a relatively small increase in
temperature. Source: After T. S. Carswell and H. K.
Nason. Figure 7.10 Effect of temperature on the impact
strength of various plastics. Small changes in
temperature can have a significant effect on impact
strength. Source: P. C. Powell.

Elongation
(a) (b) Figure 7.11 (a) Load-
elongation curve for
polycarbonate, a
thermoplastic. Source: R. P.
Kambour and R. E.
Robertson. (b) High-density
polyethylene tensile-test
specimen, showing uniform
elongation (the long, narrow
region in the specimen).

General Recommendations for Plastic Products
TABLE 7.3
Design requirement Applications Plastics
Mechanical strength Gears, cams, rollers, valves, fan
blades, impellers, pistons
Acetal, nylon, phenolic,
polycarbonate
Functional and decorative Handles, knobs, camera and
battery cases, trim moldings, pipe
fittings
ABS, acrylic, cellulosic,
phenolic, polyethylene,
polypropylene, polystyrene,
polyvinyl chloride
Housings and hollow shapes Power tools, pumps, housings,
sport helmets, telephone cases
ABS, cellulosic, phenolic,
polycarbonate, polyethylene,
polypropylene, polystyrene
Functional and transparent Lenses, goggles, safety glazing,
signs, food-processing
equipment, laboratory hardware
Acrylic, polycarbonate,
polystyrene, polysulfone
Wear resistance Gears, wear strips and liners,
bearings, bushings, roller-skate
wheels
Acetal, nylon, phenolic,
polyimide, polyurethane,
ultrahigh molecular weight
polyethylene

Load-Elongation Curve for Rubber
Figure 7.12 Typical load-elongation
curve for rubbers. The clockwise lop,
indicating the loading and the
unloading paths, displays the hysteresis
loss. Hysteresis gives rubbers the
capacity to dissipate energy, damp
vibraion, and absorb shock loading, as
is necessary in automobile tires and in
vibration dampers placed under
machinery.

CHAPTER 8
Ceramics, Graphite, and Diamond:
Structure, General Properties, and
Applications

Examples of Ceramics
(a) (b)
Figure 8.1 A variety of ceramic components. (a) High-strength alumina for high-temperature
applications. (b) Gas-turbine rotors made of silicon nitride. Source: Wesgo Div., GTE.

Types and
General
Characteristics
of Ceramics
TABLE 8.1
Type General Characteristics
Oxide ceramics
Alumina High hardness, moderate strength; most widely used ceramic;
cutting tools, abrasives, electrical and thermal insulation.
Zirconia High strength and toughness; thermal expansion close to cast iron;
suitable for heat engine components.
Carbides
Tungsten carbide Hardness, strength, and wear resistance depend on cobalt binder
content; commonly used for dies and cutting tools.
Titanium carbide Not as tough as tungsten carbide; has nickel and molybdenum as
the binder; used as cutting tools.
Silicon carbide High-temperature strength and wear resistance; used for heat
engines and as abrasives.
Nitrides
Cubic boron nitride Second-hardest substance known, after diamond; used as abrasives
and cutting tools.
Titanium nitride Gold in color; used as coatings because of low frictional
characteristics.
Silicon nitride High resistance to creep and thermal shock; used in heat engines.
Sialon Consists of silicon nitrides and other oxides and carbides; used as
cutting tools.
Cermets Consist of oxides, carbides, and nitrides; used in high-temperature
applications.
Silica High temperature resistance; quartz exhibits piezoelectric effect;
silicates containing various oxides are used in high-temperature
nonstructural applications.
Glasses Contain at least 50 percent silica; amorphous structures; several
types available with a range of mechanical and physical properties.
Glass ceramics Have a high crystalline component to their structure; good thermal-
shock resistance and strong.
Graphite Crystalline form of carbon; high electrical and thermal
conductivity; good thermal shock resistance.
Diamond Hardest substance known; available as single crystal or
polycrystalline form; used as cutting tools and abrasives and as dies
for fine wire drawing.

Properties of Various Ceramics at Room
Temperature
TABLE 8.2
Material Symbol
Transverse
rupture
strength
(MPa)
Compressive
strength
(MPa)
Elastic
modulus
(GPa)
Hardness
(HK)
Poisson’s
ratio (ν)
Density
(kg/m3
)
Aluminum
oxide
Al2O3 140–240 1000–2900 310–410 2000–3000 0.26 4000–4500
Cubic boron
nitride
CBN 725 7000 850 4000–5000 — 3480
Diamond — 1400 7000 830–1000 7000–8000 — 3500
Silica, fused SiO2 — 1300 70 550 0.25 —
Silicon
carbide
SiC 100–750 700–3500 240–480 2100–3000 0.14 3100
Silicon
nitride
Si3 N4 480–600 — 300–310 2000–2500 0.24 3300
Titanium
carbide
TiC 1400–1900 3100–3850 310–410 1800–3200 — 5500–5800
Tungsten
carbide
WC 1030–2600 4100–5900 520–700 1800–2400 — 10,000–15,000
Partially
stabilized
zirconia
PSZ 620 — 200 1100 0.30 5800
Note: These properties vary widely depending on the condition of the material.

Properties of Various Glasses
TABLE 8.3
Soda-lime
glass
Lead glass Borosilicate
glass
96 Percent
silica
Fused
silica
Density High Highest Medium Low Lowest
Strength Low Low Moderate High Highest
Resistance to thermal
shock
Low Low Good Better Best
Electrical resistivity Moderate Best Good Good Good
Hot workability Good Best Fair Poor Poorest
Heat treatability Good Good Poor None None
Chemical resistance Poor Fair Good Better Best
Impact-abrasion
resistance
Fair Poor Good Good Best
Ultraviolet-light
transmission
Poor Poor Fair Good Good
Relative cost Lowest Low Medium High Highest

Graphite Components
Figure 8.2 Various
engineering
components made of
graphite. Source: Poco
Graphite, Inc., a Unocal
Co.

CHAPTER 9
Composite Materials: Structure, General
Properties, and Applications

Application of Advanced Composite Materials
Figure 9.1
Application of
advanced
composite
materials in
Boeing 757-200
commercial
aircraft. Source:
Boeing
Commercial
Airplane
Company.

Methods of Reinforcing Plastics
illustration of methods
of reinforcing plastics
(matrix) with (a)
particles, and (b) short
or long fibers or
flakes. The four layers
of continuous fibers in
illustration (c) are
assembled into a
laminate structure.

Types and General Characteristics of
Composite Materials
TABLE 9.1
Material Characteristics
Fibers
Glass High strength, low stiffness, high density; lowest cost; E (calcium aluminoborosilicate) and S
(magnesia-aluminosilicate) types commonly used.
Graphite Available as high-modulus or high-strength; low cost; less dense than glass.
Boron High strength and stiffness; highest density; highest cost; has tungsten filament at its center.
Aramids (Kevlar) Highest strength-to-weight ratio of all fibers; high cost.
Other fibers Nylon, silicon carbide, silicon nitride, aluminum oxide, boron carbide, boron nitride, tantalum
carbide, steel, tungsten, molybdenum.
Matrix materials
Thermosets Epoxy and polyester, with the former most commonly used; others are phenolics,
fluorocarbons, polyethersulfone, silicon, and polyimides.
Thermoplastics Polyetheretherketone; tougher than thermosets but lower resistance to temperature.
Metals Aluminum, aluminum-lithium, magnesium, and titanium; fibers are graphite, aluminum oxide,
silicon carbide, and boron.
Ceramics Silicon carbide, silicon nitride, aluminum oxide, and mullite; fibers are various ceramics.

Strength and Stiffness of Reinforced Plastics
Figure 9.3 Specific tensile strength (tensile strength-to-density ratio) and specific tensile modulus
(modulus of elasticity-to-density ratio) for various fibers used in reinforced plastics. Note the wide
range of specific strengths and stiffnesses available.

Typical Properties of Reinforcing Fibers
TABLE 9.2
Type
Tensile
strength
(MPa)
Elastic
modulus
(GPa)
Density
( kg/m
3
) Relative cost
Boron 3500 380 2600 Highest
Carbon
High strength 3000 275 1900 Low
High modulus 2000 415 1900 Low
Glass
E type 3500 73 2480 Lowest
S type 4600 85 2540 Lowest
Kevlar
29 2800 62 1440 High
49 2800 117 1440 High
Note: These properties vary significantly depending on the material and method of preparation.

Fiber Reinforcing
Figure 9.4 (a) Cross-section of a tennis racket, showing graphite and aramid (Kevlar) reinforcing fibers. Source:
J. Dvorak, Mercury Marine Corporation, and F. Garrett, Wilson Sporting Goods Co. (b) Cross-section of boron
fiber-reinforced composite material.

Effect of Fiber Type on Fiber-Reinforced Nylon
Figure 9.5 The effect
of type of fiber on
various properties of
fiber-reinforced nylon
(6,6). Source: NASA.

Fracture Surfaces of Fiber-Reinforced Epoxy
Composites
(a) (b)
Figure 9.6 (a) Fracture surface of glass-fiber reinforced epoxy composite. The fibers are
10 µm (400 µin.) in diameter and have random orientation. (b) Fracture surface of a
graphite-fiber reinforced epoxy composite. The fibers, 9 µm-11 µm in diameter, are in
bundles and are all aligned in the same direction. Source: L. J. Broutman.

Tensile Strength of Glass-Reinforced Polyester
Figure 9.7 The tensile strength
of glass-reinforced polyester as a
function of fiber content and
fiber direction in the matrix.
Source: R. M. Ogorkiewicz, The
Engineering Properties of
Plastics. Oxford: Oxford
University Press, 1977.

Example of Advanced Materials Construction
Figure 9.8 Cross-section of a
composite sailboard, an example
of advanced materials
construction. Source: K.
Easterling, Tomorrow’s Materials
(2d ed.), p. 133. Institute of
Metals, 1990.

Metal-Matrix Composite Materials and
Applications
TABLE 9.3
Fiber Matrix Applications
Graphite Aluminum
Magnesium
Lead
Copper
Satellite, missile, and helicopter structures
Space and satellite structures
Storage-battery plates
Electrical contacts and bearings
Boron Aluminum
Magnesium
Titanium
Compressor blades and structural supports
Antenna structures
Jet-engine fan blades
Alumina Aluminum
Lead
Magnesium
Superconductor restraints in fission power reactors
Storage-battery plates
Helicopter transmission structures
Silicon carbide Aluminum, titanium
Superalloy (cobalt-base)
High-temperature structures
High-temperature engine components
Molybdenum, tungsten Superalloy High-temperature engine components

CHAPTER 10
Fundamentals of Metal-Casting

Cast Structures of Metals
Figure 10.1 Schematic illustration of
three cast structures of metals
solidified in a square mold: (a) pure
metals; (b) solid-solution alloys; and
(c) structure obtained by using
nucleating agents. Source: G. W.
Form, J. F. Wallace, J. L. Walker, and
A. Cibula.

Preferred Texture Development
Figure 10.2 Development of a preferred texture at a cool mold wall. Note that only
favorably oriented grains grow away from the surface of the mold.

Alloy Solidification
illustration of alloy
solidification and
temperature
distribution in the
solidifying metal.
Note the formation of
dendrites in the mushy
zone.

Solidification Patterns
Figure 10.4 (a) Solidification patterns for gray cast iron in a 180-mm (7-in.) square casting. Note that
after 11 min. of cooling, dendrites reach each other, but the casting is still mushy throughout. It takes
about two hours for this casting to solidify completely. (b) Solidification of carbon steels in sand and
chill (metal) molds. Note the difference in solidification patterns as the carbon content increases.
Source: H. F. Bishop and W. S. Pellini.

Cast Structures
Figure 10.5
Schematic
illustration of three
basic types of cast
structures: (a)
columnar dendritic;
(b) equiaxed
dendritic; and (c)
equiaxed
nondendritic.
Source: D. Apelian.
Figure 10.6 Schematic illustration of cast structures
in (a) plane front, single phase, and (b) plane front,
two phase. Source: D. Apelian.

Riser-Gated Casting
of a typical riser-gated casting.
Risers serve as reservoirs,
supplying molten metal to the
casting as it shrinks during
solidification. See also Fig. 11.4
Source: American Foundrymen’s
Society.

Fluidity Test
Figure 10.8 A test method for fluidity using
a spiral mold. The fluidity index is the length
of the solidified metal in the spiral passage.
The greater the length of the solidified metal,
the greater is its fluidity.

Temperature Distribution
Figure 10.9 Temperature
distribution at the interface of the
mold wall and the liquid metal
during solidification of metals in
casting.

Solidification Time
Figure 10.10 Solidified skin on a
steel casting. The remaining
molten metal is poured out at the
times indicated in the figure.
Hollow ornamental and decorative
objects are made by a process
called slush casting, which is based
on this principle. Source: H. F.
Taylor, J. Wulff, and M. C.
Flemings.

Solidification Contraction for Various Cast
Metals
TABLE 10.1
Metal or alloy
Volumetric
solidification
contraction (%) Metal or alloy
Volumetric
solidification
contraction (%)
Aluminum 6.6 70%Cu–30%Zn 4.5
Al–4.5%Cu 6.3 90%Cu–10%Al 4
Al–12%Si 3.8 Gray iron Expansion to 2.5
Carbon steel 2.5–3 Magnesium 4.2
1% carbon steel 4 White iron 4–5.5
Copper 4.9 Zinc 6.5
Source: After R. A. Flinn.

Hot Tears
Figure 10.11 Examples of hot tears in castings. These defects occur because
the casting cannot shrink freely during cooling, owing to constraints in
various portions of the molds and cores. Exothermic (heat-producing)
compounds may be used (as exothermic padding) to control cooling at critical
sections to avoid hot tearing.

Casting Defects
Figure 10.12 Examples of common defects in castings. These defects can be minimized or eliminated by
proper design and preparation of molds and control of pouring procedures. Source: J. Datsko.

Internal and External Chills
Figure 10.13
Various types of
(a) internal and
(b) external chills
(dark areas at
corners), used in
castings to
eliminate porosity
caused by
shrinkage. Chills
are placed in
regions where
there is a larger
volume of metals,
as shown in (c).

Solubility of Hydrogen in Aluminum
Figure 10.14 Solubility of hydrogen in
aluminum. Note the sharp decrease in
solubility as the molten metal begins to
solidify.

CHAPTER 11
Metal-Casting Processes

Summary of
Casting
Processes
TABLE 11.1
Process Advantages Limitations
Sand Almost any metal cas t; no limit
to size,shape or weight; low
tooling cost.
Some finishing required;
somewhat coars e finis h; wide
tolerances.
Shell mold Gooddimensional accuracy and
surface finish; highproduction
rate .
Part size limited; expensive
patterns andequipment
required.
Expendable pattern Most metals cast withno limit
to size; complex shapes
Patterns have lowstrengthand
can be cos tly for lowquantities
Plaster mold Intricate shapes; good
dimens ional accuracy and
finish; lowporos ity.
Limitedto nonferrous metals;
limitedsize andvolume of
production; moldmaking time
relatively long.
Ceramic mold Intricate shapes; close
tolerance parts; good surface
finish.
Limitedsize.
Investment Intricate shapes; excellent
surface finishandaccuracy;
almost any metal cast.
Part size limited; expensive
patterns ,molds,andlabor.
Permanent mold Goodsurface finis hand
dimens ional accuracy; low
poros ity; highproductionrate .
Highmold cost; limitedshape
and intricacy; not suitable for
high-melting-point metals .
Die Excellent dimensional accuracy
andsurface finis h; high
productionrate .
Die cost is high; part size
limited; usually limitedto
nonferrous metals; long lead
time.
Centrifugal Large cylindrical parts with
goodquality; highproduction
rate .
Equipment is expensive; part
shape limited.

Die-Casting Examples
(a) (b)
Figure 11.1 (a) The Polaroid PDC-2000 digital camera with a AZ91D die-cast, high purity
magnesium case. (b) Two-piece Polaroid camera case made by the hot-chamber die casting
process. Source: Courtesy of Polaroid Corporation and Chicago White Metal Casting, Inc.

General Characteristics of Casting Processes
TABLE 11.2
Typical Weig ht (kg)
Typical
surface Sectionthic kness (mm)
Process
materials
cast Minimum Maximum
finish
(µm, Ra) Porosity*
Shape
complexity*
Dimensional
accuracy* Minimum Maximum
Sand All 0.05 No limit 5-25 4 1-2 3 3 No limit
Shell All 0.05 100+ 1-3 4 2-3 2 2 --
Expendable
mold
pattern All 0.05 No limit 5-20 4 1 2 2 No limit
Plas ter
mold
Nonferrous
(Al,Mg,Zn,
Cu) 0.05 50+ 1-2 3 1-2 2 1 --
Investment
All
(High melting
pt.) 0.005 100+ 1-3 3 1 1 1 75
Permanent
mold All 0.5 300 2-3 2-3 3-4 1 2 50
Die
Nonferrous
(Al,Mg,Zn,
Cu) <0.05 50 1-2 1-2 3-4 1 0.5 12
Centrifugal All -- 5000+ 2-10 1-2 3-4 3 2 100
*Relative rating:1 bes t,5 wors t.
Note : These ratings are only general; significant variations can occur,depending on the methods used.

Casting Examples
Figure 11.2 Typical gray-
iron castings used in
automobiles, including
transmission valve body
(left) and hub rotor with
disk-brake cylinder (front).
Source: Courtesy of Central
Foundry Division of General
Motors Corporation.
Figure 11.3 A cast
transmission housing.

Sand Mold Features
Figure 11.4 Schematic illustration of a sand mold, showing various features.

Figure 11.5 Outline of production steps in a typical sand-casting operation.
Steps in Sand Casting

Pattern Material Characteristics
TABLE 11.3
Ratinga
Characteristic Wood Aluminum Steel Plastic Cast iron
Machinability E G F G G
Wear resistance P G E F E
Strength F G E G G
Weightb E G P G P
Repairability E P G F G
Resistance to:
Corrosionc E E P E P
Swellingc P E E E E
aE, Excellent; G, good; F, fair; P, poor.
bAs a factor in operator fatigue.
cBy water.
Source: D.C. Ekey and W.R. Winter, Introduction to Foundry Technology. New York.
McGraw-Hill, 1958.

Patterns for Sand Casting
Figure 11.6 A typical metal
match-plate pattern used in
sand casting.
Figure 11.7 Taper on patterns for
ease of removal from the sand mold.

Examples of Sand Cores and Chaplets
Figure 11.8 Examples of sand cores showing core prints and chaplets to support cores.

Squeeze Heads
Figure 11.9 Various designs
of squeeze heads for mold
making: (a) conventional
flat head; (b) profile head;
(c) equalizing squeeze
pistons; and (d) flexible
diaphragm. Source: ©
Institute of British
Foundrymen. Used with
permission.

Vertical Flaskless Molding
Figure 11.10 Vertical flaskless molding. (a) Sand is squeezed between two halves of the pattern. (b)
Assembled molds pass along an assembly line for pouring.

Sequence of Operations for Sand Casting
Figure 11.11 Schematic illustration of the sequence of operations for sand casting. Source: Steel
Founders' Society of America. (a) A mechanical drawing of the part is used to generate a design for the
pattern. Considerations such as part shrinkage and draft must be built into the drawing. (b-c) Patterns
have been mounted on plates equipped with pins for alignment. Note the presence of core prints designed
to hold the core in place. (d-e) Core boxes produce core halves, which are pasted together. The cores will
be used to produce the hollow area of the part shown in (a). (f) The cope half of the mold is assembled by
securing the cope pattern plate to the flask with aligning pins, and attaching inserts to form the sprue and
risers. (continued)

Figure 11.11 (g) The flask is rammed with sand and the plate and inserts are removed. (g) The drag half is
produced in a similar manner, with the pattern inserted. A bottom board is placed below the drag and aligned
with pins. (i) The pattern, flask, and bottom board are inverted, and the pattern is withdrawn, leaving the
appropriate imprint. (j) The core is set in place within the drag cavity. (k) The mold is closed by placing the
cope on top of the drag and buoyant forces in the liquid, which might lift the cope. (l) After the metal solidifies,
the casting is removed from the mold. (m) The sprue and risers are cut off and recycled and the casting is
cleaned, inspected, and heat treated (when necessary).
Sequence of Operations for Sand Casting (cont.)

Surface Roughness for Various Metalworking Processes
Figure 11.12 Surface roughness in casting and other metalworking processes. See also Figs. 22.14 and
26.4 for comparison with other manufacturing processes.

Dump-Box Technique
Figure 11.13 A common
method of making shell
molds. Called dump-box
technique, the limitations are
the formation of voids in the
shell and peelback (when
sections of the shell fall off
as the pattern is raised).

Composite Molds
Figure 11.14 (a) Schematic illustration of a semipermanent composite mold. Source: Steel
Castings Handbook, 5th ed. Steel Founders' Society of America, 1980. (b) A composite
mold used in casting an aluminum-alloy torque converter. This part was previously cast in
an all-plaster mold. Source: Metals Handbook, vol. 5, 8th ed.

Expendable Pattern Casting
Figure 11.15
Schematic
illustration of the
expendable
pattern casting
process, also
known as lost
foam or
evaporative
casting.

Ceramic Molds
Figure 11.16 Sequence of operations in
making a ceramic mold. Source: Metals
Handbook, vol. 5, 8th ed.
Figure 11.17 A typical ceramic
mold (Shaw process) for casting
steel dies used in hot forging.
Source: Metals Handbook, vol.
5, 8th ed.

Figure 11.18
Schematic
illustration of
investment
casting, (lost-
wax process).
Castings by this
method can be
made with very
fine detail and
from a variety of
metals. Source:
Steel Founders'
Society of
America.
Investment
Casting

Investment Casting of a Rotor
Figure 11.19 Investment casting of an integrally cast rotor for a gas turbine. (a) Wax pattern assembly.
(b) Ceramic shell around wax pattern. (c) Wax is melted out and the mold is filled, under a vacuum,
with molten superalloy. (d) The cast rotor, produced to net or near-net shape. Source: Howmet
Corporation.

Investment and Conventionally Cast Rotors
Figure 11.20 Cross-
section and
microstructure of two
rotors: (top)
investment-cast;
(bottom) conventionally
cast. Source: Advanced
Materials and
Processes, October
1990, p. 25 ASM
International

Vacuum-Casting Process
Figure 11.21 Schematic illustration of the vacuum-casting process. Note that the mold has a
bottom gate. (a) Before and (b) after immersion of the mold into the molten metal. Source:
From R. Blackburn, "Vacuum Casting Goes Commercial," Advanced Materials and Processes,
February 1990, p. 18. ASM International.

Pressure Casting
Figure 11.22 (a) The bottom-pressure casting process utilizes graphite molds for the production of
steel railroad wheels. Source: The Griffin Wheel Division of Amsted Industries Incorporated. (b)
Gravity-pouring method of casting a railroad wheel. Note that the pouring basin also serves as a riser.
Railroad wheels can also be manufactured by forging.

Hot- and Cold-Chamber Die-Casting
Figure 11.23 (a) Schematic illustration of the hot-chamber die-casting process. (b) Schematic
illustration of the cold-chamber die-casting process. Source: Courtesy of Foundry Management and
Technology.
(a) (b)

Cold-Chamber Die-Casting Machine
(a)
Figure 11.24 (a) Schematic illustration of a cold-chamber die-casting machine.
These machines are large compared to the size of the casting because large forces are
required to keep the two halves of the dies closed.

Figure 11.24 (b) 800-ton hot-chamber die-casting machine, DAM 8005 (made
in Germany in 1998). This is the largest hot-chamber machine in the world
and costs about $1.25 million.
(b)
Hot-Chamber Die-Casting Machine

Die-Casting Die Cavities
Figure 11.25 Various types of cavities in a die-casting die. Source: Courtesy of
American Die Casting Institute.
Figure 11.26 Examples of
cast-in- place inserts in die
casting. (a) Knurled
bushings. (b) Grooved
threaded rod.

Properties and Typical Applications of
Common Die-Casting Alloys
TABLE 11.4
Alloy
Ultimate
tensile
strength
(MPa)
Yield
strength
(MPa)
Elongation
in 50 mm
(%) Applications
Aluminum 380 (3.5Cu-8.5 Si) 320 160 2.5 Appliances,automotive components,
electrical motor frames andhousings
13(12Si) 300 150 2.5 Complex shapes withthinwalls,parts
requiringstrengthatelevated
temperatures
Brass 858(60Cu) 380 200 15 Plumbingfiztures,lock hardware,
bushings,ornamentalcastings
MagnesiumAZ91 B(9Al-0.7 Zn) 230 160 3 Power tools,automotive parts,sporting
goods
Zinc No.3 (4Al) 280 -- 10 Automotive parts,office equipment,
householdutensils,buildinghardware,
toys
5 (4Al-1 Cu) 320 -- 7 Appliances,automotive parts,building
hardware,business equipment
Source : Data fromAmericanDieCasting Institute

Centrifugal Casting Process
illustration of the centrifugal
casting process. Pipes,
cylinder liners, and similarly
shaped parts can be cast with
this process.

Semicentrifugal Casting
Figure 11.28 (a) Schematic illustration of the semicentrifugal casting process. Wheels with spokes can
be cast by this process. (b) Schematic illustration of casting by centrifuging. The molds are placed at
the periphery of the machine, and the molten metal is forced into the molds by centrifugal force.

Squeeze-Casting
Figure 11.29 Sequence of operations in the squeeze-casting process. This process combines the
advantages of casting and forging.

Single Crystal Casting of Turbine Blades
(c)
Figure 11.30 Methods of casting turbine blades: (a) directional solidification; (b) method to produce
a single-crystal blade; and (c) a single-crystal blade with the constriction portion still attached.
Source: (a) and (b) B. H. Kear, Scientific American, October 1986; (c) Advanced Materials and
Processes, October 1990, p. 29, ASM International.

Single Crystal Casting
Figure 11.31 Two methods of
crystal growing: (a) crystal
pulling (Czochralski process)
and (b) the floating-zone
method. Crystal growing is
especially important in the
semiconductor industry.
Source: L. H. Van Vlack,
Materials for Engineering.
Addison-Wesley Publishing
Co., Inc., 1982.

Melt Spinning
illustration of melt-spinning to
produce thin strips of
amorphous metal.

Types of Melting Furnaces
Figure 11.33 Two types of melting furnaces used in foundries: (a) crucible, and (b) cupola.

CHAPTER 12
Metal Casting: Design, Materials, and
Economics

Casting Design Modifications
Figure 12.1 Suggested design
modifications to avoid defects
in castings. Note that sharp
corners are avoided to reduce
stress concentrations.

Casting Cross-Sections
Figure 12.2 Examples of designs showing the importance of maintaining uniform cross- sections in
castings to avoid hot spots and shrinkage cavities.

Avoiding Shrinkage Cavities
design modifications to avoid
shrinkage cavities in castings.
Source: Steel Castings
Handbook, 5th ed. Steel
Founders' Society of America,
1980. Used with permission.

Chills
Figure 12.4 The use of
metal padding (chills) to
increase the rate of cooling
in thick regions in a casting
to avoid shrinkage cavities.
Source: Steel Castings
Founders' Society of
America, 1980. Used with
permission.

Normal Shrinkage Allowance for Some Metals
Cast in Sand Molds
TABLE 12.1
Metal Percent
Gray cast iron
White cast iron
Malleable cast iron
Aluminum alloys
Magnesium alloys
Yellow brass
Phosphor bronze
Aluminum bronze
High-manganese steel
0.83–1.3
2.1
0.78–1.0
1.3
1.3
1.3–1.6
1.0–1.6
2.1
2.6

Parting Line
Figure 12.5 Redesign of a
casting by making the parting
line straight to avoid defects.
Source: Steel Casting
Founders' Society of America,
1980. Used with permission.

Casting Design
Modifications
Figure 12.6
Examples of
casting design
modifications.
Source: Steel
Casting
Handbook, 5th
ed. Steel
Founders'
Society of
America, 1980.
Used with
permission.

Desirable and Undesirable Die-Casting
Practices
undesirable and desirable design
practices for die-cast parts. Note
that section-thickness uniformity is
maintained throughout the part.
Source: American Die Casting
Institute.

Mechanical Properties for Various Groups of
Cast Alloys
Figure 12.8 Mechanical properties for various groups of cast alloys. Note that gray iron has very little
ductility and toughness, compared with most other cast alloys, some of which undergo considerable
elongation and reduction of area in tension. Note also that even within the same group, the properties of
cast alloys vary over a wide range, particularly for cast steels. Source: Steel Founders' Society of
America.

Mechanical Properties for Various Groups of
Cast Alloys (cont.)
Figure 12.8 Mechanical properties for various groups of cast alloys. Note that gray iron has very little
ductility and toughness, compared with most other cast alloys, some of which undergo considerable
elongation and reduction of area in tension. Note also that even within the same group, the properties of
cast alloys vary over a wide range, particularly for cast steels. Source: Steel Founders' Society of
America.

Typical Applications for Casting and Casting
Characteristics
TABLE 12.2
Type of alloy Application Castability* Weldability* Machinability*
Aluminum Pistons, clutch housings, intake
manifolds
E F G–E
Copper Pumps, valves, gear blanks,
marine propellers
F–G F F–G
Ductile iron Crankshafts, heavy-duty gears G D G
Gray iron Engine blocks, gears, brake disks
and drums, machine bases
E D G
Magnesium Crankcase, transmission housings G–E G E
Malleable iron Farm and construction machinery,
heavy-duty bearings, railroad
rolling stock
G D G
Nickel Gas turbine blades, pump and
valve components for chemical
plants
F F F
Steel (carbon and
low alloy)
Die blocks, heavy-duty gear
blanks, aircraft undercarriage
members, rail-road wheels
F E F
Steel (high alloy) Gas turbine housings, pump and
valve components, rock crusher
jaws
F E F
White iron Mill liners, shot blasting nozzles,
railroad brake shoes, crushers and
pulverizers
G VP VP
Zinc Door handles, radiator grills, E D E
*E, excellent; G, good; F, fair; VP, very poor; D, difficult.

Manufacturing engineering and technology - Schmid and Kalpakjian

Manufacturing engineering and technology - Schmid and Kalpakjian

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Viewers also liked

Viewers also liked (20)

Similar to Manufacturing engineering and technology - Schmid and Kalpakjian

Similar to Manufacturing engineering and technology - Schmid and Kalpakjian (20)

Recently uploaded

Recently uploaded (20)

Manufacturing engineering and technology - Schmid and Kalpakjian