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CHAPTER 1
The Structure of Metals
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Chapter 1 Outline
Figure 1.1 An outline of the topics described in Chapter 1
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Body-Centered Cubic Crystal Structure
Figure 1.2 The body-centered cubic (bcc) crystal structure: (a) hard-ball model; (b) unit cell; and (c) singlecrystal with many unit cells. Source: W. G. Moffatt, et al., The Structure and Properties of Materials, Vol. 1,John Wiley & Sons, 1976.
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Face-Centered Cubic Crystal Structure
Figure 1.3 The face-centered cubic (fcc) crystal structure: (a) hard-ball model; (b) unit cell; and (c) singlecrystal with many unit cells. Source: W. G. Moffatt, et al., The Structure and Properties of Materials, Vol. 1,John Wiley & Sons, 1976.
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Hexagonal Close-Packed Crystal Structure
Figure 1.4 The hexagonal close-packed (hcp) crystal structure:(a) unit cell; and (b) singlecrystal with many unit cells.Source: W. G. Moffatt, et al., TheStructure and Properties ofMaterials, Vol. 1, John Wiley &Sons, 1976.
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Slip and Twinning
Figure 1.5 Permanent deformation (alsocalled plastic deformation) of a singlecrystal subjected to a shear stress: (a)structure before deformation; and (b)permanent deformation by slip. The sizeof the b/a ratio influences the magnitudeof the shear stress required to cause slip.
Figure 1.6 (a) Permanent deformation of a singlecrystal under a tensile load. Note that the slip planestend to align themselves in the direction of the pullingforce. This behavior can be simulated using a deck ofcards with a rubber band around them. (b) Twinningin a single crystal in tension.
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Slip Lines and Slip Bands
Figure 1.7 Schematic illustration of slip linesand slip bands in a single crystal (grain)subjected to a shear stress. A slip band consistsof a number of slip planes. The crystal at thecenter of the upper illustration is an individualgrain surrounded by other grains.
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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 forEngineering, 4th ed., 1980.
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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.
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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 bytheory.
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SolidificationFigure 1.11 Schematicillustration of the stagesduring solidification ofmolten metal; each smallsquare represents a unit cell.(a) Nucleation of crystals atrandom sites in the moltenmetal; note that thecrystallographic orientationof each site is different. (b)and (c) Growth of crystals assolidification continues. (d)Solidified metal, showingindividual grains and grainboundaries; note the differentangles at which neighboringgrains meet each other.Source: W. Rosenhain.
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Grain Sizes
TABLE 1.1ASTM No. Grains/mm2 Grains/mm3
–3–2–10123456789101112
1248163264128256512
1,0242,0484,0968,200
16,40032,800
0.72
5.61645128360
1,0202,9008,20023,00065,000
185,000520,000
1,500,0004,200,000
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Preferred Orientation
Figure 1.12 Plastic deformation ofidealized (equiaxed) grains in aspecimen subjected to compression(such as occurs in the rolling or forgingof metals): (a) before deformation; and(b) after deformation. Note htealignment of grain boundaries along ahorizontal direction; this effect isknown as preferred orientation.
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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 withrespect 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)
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Annealing
Figure 1.14 Schematic illustration of theeffects of recovery, recrystallization, andgrain growth on mechanical propertiesand on the shape and size of grains. Notethe formation of small new grains duringrecrystallization. Source: G. Sachs.
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Homologous Temperature Ranges for VariousProcesses
TABLE 1.2Process T/TmCold workingWarm workingHot working
< 0.30.3 to 0.5> 0.6
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CHAPTER 2
Mechanical Behavior, Testing, andManufacturing Properties of Materials
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Relative Mechanical Properties of Materials atRoom Temperature
TABLE 2.1Strength Hardness Toughness Stiffness Strength/DensityGlass fibersGraphite fibersKevlar fibersCarbidesMolybdenumSteelsTantalumTitaniumCopperReinforcedReinforcedThermoplasticsLead
DiamondCubic boron nitrideCarbidesHardened steelsTitaniumCast ironsCopperThermosetsMagnesiumthermosetsthermoplasticsLeadRubbers
Ductile metalsReinforced plasticsThermoplasticsWoodThermosetsCeramicsGlassCeramicsReinforcedThermoplasticsTinThermoplastics
DiamondCarbidesTungstenSteelCopperTitaniumAluminumTantalumplasticsWoodThermosets
Reinforced plasticsTitaniumSteelAluminumMagnesiumBerylliumCopper
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Tensile-Test Specimen and Machine
(b)
Figure 2.1 (a) A standard tensile-test specimen before and after pulling, showing original and finalgage lengths. (b) A typical tensile-testing machine.
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Stress-Strain Curve
Figure 2.2 A typical stress-strain curve obtained from atension test, showing variousfeatures.
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Mechanical Properties of Various Materials atRoom Temperature
TABLE 2.2 Mechanical Properties of Various Materials at Room Temperature
Metals (Wrought) E (GPa) Y (MPa) UTS (MPa)
Elongationin 50 mm
(%)Aluminum and its alloysCopper and its alloysLead and its alloysMagnesium and its alloysMolybdenum and its alloysNickel and its alloysSteelsTitanium and its alloysTungsten and its alloys
69–79105–150
1441–45
330–360180–214190–20080–130350–400
35–55076–1100
14130–30580–2070
105–1200205–1725344–1380550–690
90–600140–1310
20–55240–38090–2340345–1450415–1750415–1450620–760
45–465–350–921–5
40–3060–565–225–7
0Nonmetallic materialsCeramicsDiamondGlass and porcelainRubbersThermoplasticsThermoplastics, reinforcedThermosetsBoron fibersCarbon fibersGlass fibersKevlar fibers
70–1000820–1050
70-800.01–0.11.4–3.4
2–503.5–17
380275–415
73–8562–117
———————————
140–2600—
140—
7–8020–12035–170
35002000–30003500–4600
2800
0———
1000–510–1
00000
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.
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Loading and Unloading of Tensile-TestSpecimen
Figure 2.3 Schematic illustration of theloading and the unloading of a tensile- testspecimen. Note that, during unloading,the curve follows a path parallel to theoriginal elastic slope.
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Elongation versus % Area Reduction
Figure 2.4Approximaterelationshipbetween elongationand tensilereduction of areafor various groupsof metals.
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Construction of True Stress-True Strain Curve
Figure 2.5 (a) Load-elongationcurve in tension testing of astainless steel specimen. (b)Engineering stress-engineeringstrain curve, drawn from the datain Fig. 2.5a. (c) True stress-truestrain curve, drawn from the datain Fig. 2.5b. Note that this curvehas a positive slope, indicatingthat the material is becomingstronger as it is strained. (d) Truestress-true strain curve plotted onlog-log paper and based on thecorrected curve in Fig. 2.5c. Thecorrection is due to the triaxialstate of stress that exists in thenecked region of a specimen.
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Typical Values for K and n at RoomTemperature
TABLE 2.3K (MPa) n
Aluminum1100–O2024–T46061–O6061–T67075–O
Brass70–30, annealed85–15, cold-rolled
Cobalt-base alloy, heat-treatedCopper, annealedSteel
Low-C annealed4135 annealed4135 cold-rolled4340 annealed304 stainless, annealed410 stainless, annealed
180690205410400
900580
2070315
53010151100640
1275960
0.200.160.200.050.17
0.490.340.500.54
0.260.170.140.150.450.10
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True Stress-True Strain Curves
Figure 2.6 True stress-truestrain curves in tension atroom temperature forvarious metals. The curvesstart at a finite level ofstress: The elastic regionshave too steep a slope to beshown in this figure, and soeach curve starts at theyield stress, Y, of thematerial.
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Temperature Effects on Stress-Strain Curves
Figure 2.7 Typical effects of temperatureon stress-strain curves. Note thattemperature affects the modulus ofelasticity, the yield stress, the ultimatetensile strength, and the toughness (areaunder the curve) of materials.
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Typical Ranges of Strain and Deformation Rate inManufacturing Processes
TABLE 2.4
Process True strainDeformation rate
(m/s)Cold working
Forging, rollingWire and tube drawing
Explosive formingHot working and warm working
Forging, rollingExtrusion
MachiningSheet-metal formingSuperplastic forming
0.1–0.50.05–0.50.05–0.2
0.1–0.52–51–10
0.1–0.50.2–3
0.1–1000.1–10010–100
0.1–300.1–1
0.1–1000.05–2
10-4
-10-2
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Effect of Strain Rate on Ultimate TensileStrength
Figure 2.8 The effect of strainrate on the ultimate tensilestrength for aluminum. Notethat, as the temperatureincreases, the slopes of thecurves increase; thus, strengthbecomes more and moresensitive to strain rate astemperature increases. Source:J. H. Hollomon.
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Disk and Torsion-Test Specimens
Figure 2.9 Disk test on a brittlematerial, showing the directionof loading and the fracture path.
Figure 2.10 Typical torsion-testspecimen; it is mounted between thetwo heads of a testing machine andtwisted. Note the shear deformation ofan element in the reduced section ofthe specimen.
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Bending
Figure 2.11 Two bend-testmethods for brittle materials: (a)three-point bending; (b) four-point bending. The areas on thebeams represent the bending-moment diagrams, described intexts on mechanics of solids.Note the region of constantmaximum bending moment in(b); by contrast, the maximumbending moment occurs only atthe center of the specimen in(a).
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Hardness Tests
Figure 2.12 Generalcharacteristics ofhardness-testingmethods and formulasfor calculatinghardness. The quantityP is the load applied.Source: H. W. Hayden,et al., The Structureand Properties ofMaterials, Vol. III(John Wiley & Sons,1965).
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Brinell Testing
(c)
Figure 2.13 Indentation geometry inBrinell testing; (a) annealed metal; (b)work-hardened metal; (c) deformation ofmild steel under a spherical indenter.Note that the depth of the permanentlydeformed zone is about one order ofmagnitude larger than the depth ofindentation. For a hardness test to bevalid, this zone should be fullydeveloped in the material. Source: M. C.Shaw and C. T. Yang.
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HardnessConversion
Chart
Figure 2.14 Chartfor convertingvarious hardnessscales. Note thelimited range ofmost scales.Because of themany factorsinvolved, theseconversions areapproximate.
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S-N Curves
Figure 2.15 Typical S-Ncurves for two metals. Notethat, unlike steel, aluminumdoes not have an endurancelimit.
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Endurance Limit/Tensile Strength versusTensile Strength
Figure 2.16 Ratio of endurance limit totensile strength for various metals, as afunction of tensile strength. Becausealuminum does not have an endurance limit,the correlation for aluminum are based on aspecific number of cycles, as is seen in Fig.2.15.
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Creep Curve
Figure 2.17 Schematicillustration of a typical creepcurve. The linear segment ofthe curve (secondary) is usedin designing components for aspecific creep life.
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Impact Test Specimens
Figure 2.18 Impact testspecimens: (a) Charpy;(b) Izod.
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Failures of Materials and Fractures inTension
Figure 2.19 Schematic illustrationof types of failures in materials: (a)necking and fracture of ductilematerials; (b) Buckling of ductilematerials under a compressive load;(c) fracture of brittle materials incompression; (d) cracking on thebarreled surface of ductile materialsin compression.
Figure 2.20 Schematic illustration of the types offracture in tension: (a) brittle fracture in polycrystallinemetals; (b) shear fracture in ductile single crystals--seealso Fig. 1.6a; (c) ductile cup-and-cone fracture inpolycrystalline metals; (d) complete ductile fracture inpolycrystalline metals, with 100% reduction of area.
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Ductile Fracture
Figure 2.21 Surface of ductilefracture in low-carbon steel,showing dimples. Fracture isusually initiated at impurities,inclusions, or preexisting voids(microporosity) in the metal.Source: K.-H. Habig and D.Klaffke. Photo by BAMBerlin/Germany.
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Fracture of a Tensile-Test Specimen
Figure 2.22 Sequence of events in necking and fracture of a tensile-test specimen: (a) early stage ofnecking; (b) small voids begin to form within the necked region; (c) voids coalesce, producing aninternal crack; (d) the rest of the cross-section begins to fail at the periphery, by shearing; (e) the finalfracture surfaces, known as cup- (top fracture surface) and cone- (bottom surface) fracture.
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Deformation of Soft and Hard Inclusions
Figure 2.23 Schematic illustration of the deformation of soft and hard inclusions and of their effect on voidformation in plastic deformation. Note that, because they do not comply with the overall deformation of theductile matrix, hard inclusions can cause internal voids.
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Transition Temperature
Figure 2.24 Schematicillustration of transitiontemperature in metals.
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Brittle Fracture Surface
Figure 2.25 Fracturesurface of steel that hasfailed in a brittle manner.The fracture path istransgranular (through thegrains). Magnification:200X. Source: Courtesyof B. J. Schulze and S. L.Meiley and PackerEngineering Associates,Inc.
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Intergranular Fracture
Figure 2.26 Intergranularfracture, at two differentmagnifications. Grainsand grain boundaries areclearly visible in thismicrograph. Te fracturepath is along the grainboundaries.Magnification: left, 100X;right, 500X. Source:Courtesy of B. J. Schulzeand S. L. Meiley andPacker EngineeringAssociates, Inc.
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Fatigue-Fracture Surface
Figure 2.27 Typicalfatigue-fracture surface onmetals, showing beachmarks. Magnification:left, 500X; right, 1000X.Source: Courtesy of B. J.Schulze and S. L. Meileyand Packer EngineeringAssociates, Inc.
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Reduction in Fatigue Strength
Figure 2.28 Reductions in thefatigue strength of cast steelssubjected to various surface-finishing operations. Note that thereduction becomes greater as thesurface roughness and the strengthof the steel increase. Source: M.R. Mitchell.
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Residual Stresses
Figure 2.29 Residual stresses developed in bending a beam having a rectangular cross-section. Note that thehorizontal forces and moments caused by residual stresses in the beam must be balanced internally. Because ofnonuniform deformation during metalworking operations, most parts develop residual stresses.
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Distortion of Parts with Residual Stresses
Figure 2.30 Distortion of parts, with residual stresses, after cutting or slitting: (a) flatsheet or plate; (b) solid round rod; (c) think-walled tubing or pipe.
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CHAPTER 3
Physical Properties of Materials
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Physical Properties of Selected Materials atRoom Temperature
TABLE 3.1 Physical Properties of Selected Materials at Room TemperatureMetal Density
(kg/m3)
Melting Point(°C)
Specific heat(J/kg K)
Thermal conductivity(W/m K)
AluminumAluminum alloysBerylliumColumbium (niobium)CopperCopper alloysIronSteelsLeadLead alloysMagnesiumMagnesium alloysMolybdenum alloysNickelNickel alloysTantalum alloysTitaniumTitanium alloysTungstenZincZinc alloys
27002630–2820
185485808970
7470–89407860
6920–913011,350
8850–11,3501745
1770–178010,2108910
7750–885016,6004510
4430–470019,2907140
6640–7200
660476–654
127824681082
885–12601537
1371–1532327
182–326650
610–62126101453
1110–145429961668
1549–16493410419
386–525
900880–920
1884272385
377–435460
448–502130
126–18810251046276440
381–544142519
502–544138385402
222121–239
14652393
29–23474
15–5235
24–46154
75–13814292
12–635417
8–12166113
105–113
NonmetallicCeramicsGlassesGraphitePlasticsWood
2300–55002400–27001900–2200900–2000400–700
—580–1540
—110–330
—
750–950500–850
8401000–20002400–2800
10–170.6–1.7
5–100.1–0.40.1–0.4
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Physical Properties of Material
TABLE 3.2 Physical Properties of Materials, in Descending OrderDensity Melting point Specific heat Thermal
conductivityThermalexpansion
Electricalconductivity
PlatinumGoldTungstenTantalumLeadSilverMolybdenumCopperSteelTitaniumAluminumBerylliumGlassMagnesiumPlastics
TungstenTantalumMolybdenumColumbiumTitaniumIronBerylliumCopperGoldSilverAluminumMagnesiumLeadTinPlastics
WoodBerylliumPorcelainAluminumGraphiteGlassTitaniumIronCopperMolybdenumTungstenLead
SilverCopperGoldAluminumMagnesiumGraphiteTungstenBerylliumZincSteelTantalumCeramicsTitaniumGlassPlastics
PlasticsLeadTinMagnesiumAluminumCopperSteelGoldCeramicsGlassTungsten
SilverCopperGoldAluminumMagnesiumTungstenBerylliumSteelTinGraphiteCeramicsGlassPlasticsQuartz
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SpecificStrength and
SpecificStiffness
Figure 3.1 Specificstrength (tensilestrength/density) andspecific stiffness (elasticmodulus/density) forvarious materials atroom temperature. (Seealso Chapter 9.) Source:M.J. Salkind.
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Specific Strength versus Temperature
Figure 3.2 Specific strength (tensile strength/density) for a variety of materials as afunction of temperature. Note the useful temperature range for these materials and thehigh values for composite materials.
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CHAPTER 4
Metal Alloys: Their Structure andStrengthening by Heat Treatment
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Induction-Hardened Surface
Figure 4.1 Cross-section ofgear teeth showinginduction-hardenedsurfaces. Source: TOCCODiv., Park-Ohio Industries,Inc.
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Chapter 4 Outline
Figure 4.2 Outline of topics described in Chapter 4.
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Two-Phase System
Figure 4.3 (a) Schematic illustration of grains, grain boundaries, and particles dispersed throughoutthe structure of a two-phase system, such as a lead-copper alloy. The grains represent lead in solidsolution 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 haveseparate compositions and properties.
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Cooling Curve
Figure 4.4 Cooling curve forthe solidification of puremetals. Note that freezing takesplace at a constant temperature;during freezing the latent heatof solidification is given off.
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Nickel-Copper Alloy Phase Diagram
Figure 4.5 Phasediagram for nickel-copper alloy systemobtained at a slowrate of solidification.Note that pure nickeland pure copper eachhas one freezing ormelting temperature.The top circle on theright depicts thenucleation ofcrystals. The secondcircle shows theformation ofdendrites (seeSection 10.2). Thebottom circle showsthe solidified alloy,with grainboundaries.
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Mechanical Properties of Copper-Nickel andCopper-Zinc Alloys
Figure 4.6 Mechanicalproperties of copper-nickeland copper-zinc alloys as afunction of theircomposition. The curvesfor zinc are short, becausezinc has a maximum solidsolubility of 40% in copper.Source: L. H. Van Vlack;Materials for Engineering.Addison-WesleyPublishing Co., Inc., 1982.
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Lead-Tin Phase Diagram
Figure 4.7 Thelead-tin phasediagram. Note thatthe composition ofthe eutectic point forthis alloy is 61.9%Sn-38.1% Pb. Acomposition eitherlower or higher thanthis ratio will have ahigher liquidustemperature.
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Iron-Iron Carbide Phase Diagram
Figure 4.8 The iron-ironcarbide phase diagram.Because of theimportance of steel as anengineering material, thisdiagram is one of themost important of allphase diagrams.
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Austenite, Ferrite, and Martensite
Figure 4.9 The unit cells for (a) austenite, (b) ferrite, and (c) martensite. The effect of percentage ofcarbon (by weight) on the lattice dimensions for martensite is shown in (d). Note the interstitial positionof 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.
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Iron-Carbon Alloy Above and Below EutectoidTemperature
Figure 4.10 Schematic illustrationof the microstructures for an iron-carbon alloy of eutectoidcomposition (0.77% carbon), aboveand below the eutectoid temperatureof 727 °C (1341 °F).
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Pearlite Microstructure
Figure 4.11 Microstructure ofpearlite in 1080 steel, formedfrom austenite of eutectoidcomposition. In this lamellarstructure, the lighter regions areferrite, and the darker regions arecarbide. Magnification: 2500X.Source: Courtesy of USXCorporation.
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Extended Iron-Carbon Phase Diagram
Figure 4.12 Phase diagram for the iron-carbon system with graphite (insteadof cementite) as the stable phase. Note that this figure is an extended versionof Fig. 4.8.
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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 ironsolidified as white cast iron, with the carbon present as cementite, and was heat treated to graphitize the carbon.Source: ASM International.
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Austenite toPearlite
Transformation
Figure 4.14 (a) Austenite-to-pearlite transformationof iron-carbon alloy as afunctionof time andtemperature. (b)Isothermal transformationdiagram obtained from (a)for a transformationtemperature of 675 °C(1247 °F). (continued)
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Austenite to Pearlite Transformation (cont.)
Figure 4.14 (c) Microstructuresobtained for a eutectoid iron-carbonalloy as a function of cooling rate.Source: ASM International.
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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 carbideshape. Carbides in the pearlite are lamellar. Fine pearlite is obtained by increasing the cooling rate. Thespheroidite structure has spherelike carbide particles. Note htat the percentage of pearlite begins to decreaseafter 0.77% carbon. Source: L. H. Van Vlack; Materials for Engineering. Addison-Wesley Publishing Co.,Inc., 1982.
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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, withincreasing amounts of pearlite and iron carbide. Source: L. H. Van Vlack; Materials for Engineering.Addison-Wesley Publishing Co., Inc., 1982.
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Eutectoid Steel Microstructure
Figure 4.17 Microstructureof eutectoid steel.Spheroidite is formed bytempering the steel at 700 °C(1292 °F). Magnification:1000X. Source: Courtesy ofUSX Corporation.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 4-20
Martensite
(b)
Figure 4.18 (a) Hardness of martensite, as a function of carbon content. (b) Micrograph of martensitecontaining 0.8% carbon. The gray platelike regions are martensite; they have the same composition as theoriginal austenite (white regions). Magnification: 1000X. Source: Courtesy of USX Corporation.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 4-21
Hardness of Tempered Martensite
Figure 4.19 Hardnessof temperedmartensite, as afunction of temperingtime, for 1080 steelquenched to 65 HRC.Hardness decreasesbecause the carbideparticles coalesce andgrow in size, therebyincreasing theinterparticle distanceof the softer ferrite.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 4-22
End-QuenchHardenability
Test
Figure 4.20 (a)End-quench testand cooling rate.(b) Hardenabilitycurves for fivedifferent steels, asobtained from theend-quench test.Small variations incomposition canchange the shape ofthese curves. Eachcurve is actually aband, and its exactdetermination isimportant in theheat treatment ofmetals, for bettercontrol ofproperties. Source:L. H. Van Vlack;Materials forEngineering.Addison-WesleyPublishing Co.,Inc., 1982.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 4-23
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 forEngineering. Addison-Wesley Publishing Co., Inc., 1982.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 4-24
Age Hardening
Figure 4.22 The effect of agingtime and temperature on the yieldstress of 2014-T4 aluminum alloy.Note that, for each temperature,there is an optimal aging time formaximum strength.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 4-25
Outline of Heat Treatment Processes forSurface Hardening
TABLE 4.1Process Metals hardened Element added to
surfaceProcedure General Characteristics Typical applications
Carburizing Low-carbon steel(0.2% C), alloysteels (0.08–0.2%C)
C Heat steel at 870–950 °C (1600–1750°F) in an atmosphere of carbonaceousgases (gas carburizing) or carbon-containing solids(pack carburizing). Then quench.
A hard, high-carbon surface isproduced. Hardness 55 to 65HRC. Case depth < 0.5–1.5 mm( < 0.020 to 0.060 in.). Somedistortion of part during heattreatment.
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 carbonaceousgas 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.). Lessdistortion than incarburizing.
Bolts, nuts, gears
Cyaniding Low-carbon steel(0.2% C), alloysteels (0.08–0.2%C)
C and N Heat steel at 760–845 °C (1400–1550°F) in a molten bath of solutions ofcyanide (e.g., 30% sodium cyanide) andother salts.
Surface hardness up to 65 HRC.Case depth 0.025 to 0.25 mm(0.001 to 0.010 in.). Somedistortion.
Bolts, nuts, screws, smallgears
Nitriding Steels (1% Al,1.5% Cr, 0.3%Mo), alloy steels(Cr, Mo), stainlesssteels, high-speedtool steels
N Heat steel at 500–600 °C (925–1100 °F)in an atmosphere of ammonia gas ormixtures of molten cyanide salts. Nofurther treatment.
Surface hardness up to 1100HV. Case depth 0.1 to 0.6 mm(0.005 to 0.030 in.) and 0.02 to0.07 mm (0.001to 0.003 in.) for high speedsteel.
Gears, shafts, sprockets,valves, cutters, boringbars, fuel-injection pumpparts
Boronizing Steels B Part is heated using boron-containinggas or solid in contact with part.
Extremely hard and wearresistant surface. Case depth0.025– 0.075 mm (0.001–0.003 in.).
Tool and die steels
Flame hardening Medium-carbonsteels, cast irons
None Surface is heated with an oxyacetylenetorch, then quenched with water spray orother quenching methods.
Surface hardness 50 to 60 HRC.Case depth 0.7 to 6 mm (0.030to 0.25 in.). Little distortion.
Gear and sprocket teeth,axles, crankshafts, pistonrods, lathe beds andcenters
Inductionhardening
Same as above None Metal part is placed in copper inductioncoils and is heated by high frequencycurrent, then quenched.
Same as above Same as above
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Heat Treatment ProcessesFigure 4.23 Heat-treating temperature ranges forplain-carbon steels, as indicated on the iron-ironcarbide phase diagram. Source: ASMInternational.
Figure 4.24 Hardness of steels in the quenched andnormalized conditions, as a function of carbon content.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 4-27
Properties of Oil-Quenched Steel
Figure 4.25 Mechanical properties ofoil-quenched 4340 steel, as a functionof tempering temperature. Source:Courtesy of LTV Steel Company
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 4-28
Induction Heating
Figure 4.26 Types of coils used in induction heating of various surfaces of parts.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 5-1
CHAPTER 5
Ferrous Metals and Alloys: Production,General Properties, and Applications
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 5-2
Blast Furnace
Figure 5.1Schematicillustration of ablast furnace.Source: Courtesyof American Ironand Steel Institute.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 5-3
Electric Furnaces
Figure 5.2 Schematic illustration of types of electric furnaces: (a) direct arc, (b) indirect arc, and (c) induction.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 5-4
Basic-Oxygen Process
Figure 5.3 Schematicillustrations showing(a) charging, (b)melting, and (c)pouring of molten ironin a basic-oxygenprocess. Source:Inland Steel Company
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ContinuousCasting
Figure 5.4 Thecontinuous-castingprocess for steel.Typically, the solidifiedmetal descends at a speedof 25 mm/s (1 in./s).Note that the platform isabout 20 m (65 ft) aboveground level. Source:Metalcaster's Referenceand Guide, AmericanFoundrymen's Society.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 5-6
Typical Selection of Carbon and Alloy Steels forVarious Applications
TABLE 5.1Product Steel Product SteelAircraft forgings,
tubing, fittingsAutomobile bodiesAxlesBall bearings and racesBoltsCamshaftsChains (transmission)Coil springsConnecting rodsCrankshafts (forged)
4140, 8740
10101040, 4140521001035, 4042, 48151020, 10403135, 314040631040, 3141, 43401045, 1145, 3135, 3140
Differential gearsGears (car and truck)Landing gearLock washersNutsRailroad rails and wheelsSprings (coil)Springs (leaf)TubingWireWire (music)
40234027, 40324140, 4340, 87401060313010801095, 4063, 61501085, 4063, 9260, 615010401045, 10551085
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 5-7
Mechanical Properties of Selected Carbon andAlloy Steels in Various Conditions
TABLE 5.2 Typical Mechanical Properties of Selected Carbon and Alloy Steels in the Hot-Rolled,Normalized, and Annealed ConditionAISI Condition Ultimate
tensilestrength(MPa)
YieldStrength(MPa)
Elongation in50 mm (%)
Reduction ofarea (%)
Hardness(HB)
1020
1080
3140
4340
8620
As-rolledNormalizedAnnealedAs-rolled
NormalizedAnnealed
NormalizedAnnealed
NormalizedAnnealed
NormalizedAnnealed
448441393
1010965615891689
1279744632536
346330294586524375599422861472385357
363536121124192412222631
596766172045575036495962
143131111293293174262197363217183149
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 5-8
AISI Designation for High-Strength SheetSteel
TABLE 5.3Yield Strength Chemical
CompositionDeoxidation
Practice
psi x 103 MPa
35404550607080
100120140
240275310350415485550690830970
S = structural alloy
X = low alloy
W = weathering
D = dual phase
F = killed plus sulfide inclusion control
K = killed
O = nonkilled
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Room-Temperature Mechanical Properties andApplications of Annealed Stainless Steels
TABLE 5.4 Room-Temperature Mechanical Properties and Typical Applications of Selected AnnealedStainless Steels
AISI(UNS)
Ultimatetensile
strength(MPa)
Yieldstrength(MPa)
Elongationin 50 mm
(%) Characteristics and typical applications303(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, fertilizerparts, ketchup cooking kettles, and yeast tubs.
410(S41000)
480–520 240–310 35–25 Machine parts, pump shafts, bolts, bushings, coalchutes, cutlery, tackle, hardware, jet engine parts,mining machinery, rifle barrels, screws, andvalves.
416(S41600)
480–520 275 30–20 Aircraft fittings, bolts, nuts, fire extinguisherinserts, rivets, and screws.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 5-10
Basic Types of Tool and Die Steels
TABLE 5.5Type AISIHigh 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)SP1 to P19 (low carbon)P20 to P39 (others)L (low alloy)F (carbon-tungsten)W
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 5-11
Processing and Service Characteristics ofCommon Tool and Die Steels
TABLE 5.6 Processing and Service Characteristics of Common Tool and Die Steels
AISIdesignation
Resistance todecarburization
Resistance tocracking
Approximatehardness(HRC) Machinability Toughness
Resistance tosoftening
Resistance towear
M2 Medium Medium 60–65 Medium Low Very high Very highT1 High High 60–65 Medium Low Very high Very highT5 Low Medium 60–65 Medium Low Highest Very highH11, 12, 13 Medium Highest 38–55 Medium to high Very high High MediumA2 Medium Highest 57–62 Medium Medium High HighA9 Medium Highest 35–56 Medium High High Medium to
highD2 Medium Highest 54–61 Low Low High High to very
highD3 Medium High 54–61 Low Low High Very highH21 Medium High 36–54 Medium High High Medium to
highH26 Medium High 43–58 Medium Medium Very high HighP20 High High 28–37 Medium to high High Low Low to
mediumP21 High Highest 30–40 Medium Medium Medium MediumW1, W2 Highest Medium 50–64 Highest High Low Low to
medium
Source: Adapted from Tool Steels, American Iron and Steel Institute, 1978.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 6-1
CHAPTER 6
Nonferrous Metals and Alloys:Production, General Properties, and
Applications
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Approximate Cost per Unit Volume for WroughtMetals and Plastics Relative to Carbon Steel
TABLE 6.1 Approximate Cost per Unit Volume for Wrought Metals and Plastics Relative toCost of Carbon SteelGoldSilverMolybdenum alloysNickelTitanium alloysCopper alloysZinc alloysStainless steels
60,000600200–2503520–405–61.5–3.52–9
Magnesium alloysAluminum alloysHigh-strength low-alloy steelsGray cast ironCarbon steelNylons, acetals, and silicon rubber
*
Other plastics and elastomers*
2–42–31.41.211.1–20.2–1
*As molding compounds.Note: Costs vary significantly with quantity of purchase, supply and demand, size and shape, and various other factors.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 6-3
General Characteristics of Nonferrous Metalsand Alloys
TABLE 6.2Material CharacteristicsNonferrous 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.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 6-4
Example of Alloy Usage
Figure 6.1 Cross-section of a jetengine (PW2037)showing variouscomponents and thealloys used inmanufacturingthem. Source:Courtesy of UnitedAircraft Pratt &Whitney.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 6-5
Properties of Selected Aluminum Alloys atRoom Temperature
TABLE 6.3
Alloy (UNS) TemperUltimate tensilestrength (MPa)
Yield strength(MPa)
Elongationin 50 mm
(%)1100 (A91100)11002024 (A92024)20243003 (A93003)30035052 (A95052)50526061 (A96061)60617075 (A97075)7075
OH14
OT4O
H14O
H34OT6OT6
90125190470110150190260125310230570
3512075325401459021555275105500
35–459–2020–2219–2030–408–1625–3010–1425–3012–1716–17
11
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Manufacturing Properties and Applications ofSelected Wrought Aluminum Alloys
TABLE 6.4
Characteristics*
AlloyCorrosionresistance Machinability Weldability Typical applications
1100 A C–D A Sheet metal work, spun hollow ware, tinstock
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, andappliances; bus, truck and marine uses
6061 B C–D A Heavy-duty structures where corrosionresistance is needed, truck and marinestructures, railroad cars, furniture,pipelines, bridge rail-ings, hydraulictubing
7075 C B–D D Aircraft and other structures, keys,hydraulic fittings
* A, excellent; D, poor.
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All-Aluminum Automobile
Figure 6.2 (a) The Audi A8automobile which has an all-aluminum body structure. (b) Thealuminum body structure, showingvarious components made byextrusion, sheet forming, and castingprocesses. Source: Courtesy ofALCOA, Inc.
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Properties and Typical Forms of SelectedWrought Magnesium Alloys
TABLE 6.5
Composition (%)Ultimatetensile Yield Elongation
Alloy Al Zn Mn Zr Conditionstrength(MPa)
strength(MPa)
in 50 mm(%) Typical forms
AZ31 B 3.0 1.0 0.2 F 260 200 15 ExtrusionsH24 290 220 15 Sheet and plates
AZ80A 8.5 0.5 0.2 T5 380 275 7 Extrusions andforgings
HK31A 3Th 0.7 H24 255 200 8 Sheet and platesZK60A 5.7 0.55 T5 365 300 11 Extrusions and
forgings
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Properties and Typical Applications of SelectedWrought Copper and Brasses
TABLE 6.6
Type and UNSnumber
Nominalcomposition (%)
Ultimatetensile
strength(MPa)
Yieldstrength(MPa)
Elongationin 50 mm
(%) Typical applicationsElectrolytic 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, fireextinguishers, condenser and heatexchanger tubing
Cartridge brass, 70%(C26000)
70.0 Cu, 30.0 Zn 300–900 75–450 66–3 Radiator cores and tanks, flashlightshells, lamp fixtures, fasteners,locks, hinges, ammunitioncomponents, 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, propellershafts, rivets, valve stems,condenser plates
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 6-10
Properties and Typical Applications of SelectedWrought Bronzes
TABLE 6.7
Type and UNS numberNominal
composition (%)
Ultimatetensile
strength(MPa)
Yieldstrength(MPa)
Elongationin 50 mm
(%) Typical applicationsArchitectural bronze(C38500)
57.0 Cu, 3.0 Pb,40.0 Zn
415 (Asextruded)
140 30 Architectural extrusions, storefronts, 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, wirebrushes, chemical hardware, textilemachinery
Free-cutting phosphorbronze (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, electricalconduits, 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
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 6-11
Properties and Typical Applications of SelectedNickel Alloys
TABLE 6.8 Properties and Typical Applications of Selected Nickel Alloys (All are Trade Names)
Type and UNS numberNominal
composition (%)
Ultimatetensile
strength(MPa)
Yieldstrength(MPa)
Elongationin 50 mm
(%) Typical applicationsNickel 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 (hotrolled)
30 Cu 525 230 35 Screw-machine products, water meterparts
Monel K-500 29 Cu, 3 Al 1050 750 30 Pump shafts, valve stems, springs (agehardened)
Inconel 600 (annealed) 15 Cr, 8 Fe 640 210 48 Gas turbine parts, heat-treatingequipment, electronic parts, nuclearreactors
Hastelloy C-4 (solution-treated and quenched)
16 Cr, 15 Mo 785 400 54 High temperature stability, resistanceto stress-corrosion cracking
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Properties and Typical Applications of SelectedNickel-Base Superalloys at 870 °C
TABLE 6.9 Properties and Typical Applications of Selected Nickel-Base Superalloys at 870 °C(1600 °F) (All are Trade Names)
Alloy Condition
Ultimatetensile
strength(MPa)
Yieldstrength(MPa)
Elongationin 50 mm
(%) Typical applicationsAstroloy Wrought 770 690 25 Forgings for high temperatureHastelloy X Wrought 255 180 50 Jet engine sheet partsIN-100 Cast 885 695 6 Jet engine blades and wheelsIN-102 Wrought 215 200 110 Superheater and jet engine partsInconel 625 Wrought 285 275 125 Aircraft engines and structures,
chemical processing equipmentlnconel 718 Wrought 340 330 88 Jet engine and rocket partsMAR-M 200 Cast 840 760 4 Jet engine bladesMAR-M 432 Cast 730 605 8 Integrally cast turbine wheelsRené 41 Wrought 620 550 19 Jet engine partsUdimet 700 Wrought 690 635 27 Jet engine partsWaspaloy Wrought 525 515 35 Jet engine parts
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Properties and Typical Applications of SelectedWrought Titanium Alloys
TABLE 6.10 Properties and Typical Applications of Selected Wrought Titanium Alloys at VariousTemperaturesNominalcompos-ition(%) UNS Condition
Ultimatetensile
strength(MPa)
Yieldstrength(MPa)
Elonga-tion (%)
Reduc-tion of
area (%)Temp.(°C)
Ultimatetensile
strength(MPa)
Yieldstrength(MPa)
Elonga-tion in50 mm
(%)
Reduc-tion ofarea Typical Applications
99.5 Ti R50250 Annealed 330 240 30 55 300 150 95 32 80 Airframes; chemical,desalination, andmarine parts; platetype heat exchangers
5 Al,2.5 Sn
R54520 Annealed 860 810 16 40 300 565 450 18 45 Aircraft enginecompressor blades andducting; steam turbineblades
6 Al,4V
R56400 Annealed 1000 925 14 30 300 725 650 14 35 Rocket motor cases;blades and disks foraircraft turbines andcompressors;structural forgings andfasteners; orthopedicimplants
425 670 570 18 40550 530 430 35 50
Solution +age
1175 1100 10 20 300 980 900 10 28
12 3522 45
13 V,11 Cr,3 Al
R58010 Solution +age
1275 1210 8 — 425 1100 830 12 — High strengthfasteners; aerospacecomponents;honeycomb panels
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 7-1
CHAPTER 7
Polymers: Structure, General Propertiesand Applications
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 7-2
Range of Mechanical Properties for VariousEngineering Plastics
TABLE 7.1
Material UTS (MPa) E (GPa)Elongation
(%)Poisson’sratio (ν)
ABSABS, reinforcedAcetalAcetal, reinforcedAcrylicCellulosicEpoxyEpoxy, reinforcedFluorocarbonNylonNylon, reinforcedPhenolicPolycarbonatePolycarbonate, reinforcedPolyesterPolyester, reinforcedPolyethylenePolypropylenePolypropylene, reinforcedPolystyrenePolyvinyl chloride
28–55100
55–70135
40–7510–48
35–14070–1400
7–4855–83
70–21028–7055–70
11055
110–1607–40
20–3540–10014–837–55
1.4–2.87.5
1.4–3.510
1.4–3.50.4–1.43.5–1721–520.7–2
1.4–2.82–10
2.8–212.5–3
62
8.3–120.1–1.40.7–1.23.5–61.4–4
0.014–4
75–5—
75–25—
50–5100–510–14–2
300–100200–60
10–12–0
125–106–4
300–53–1
1000–15500–10
4–260–1
450–40
—0.35—
0.35–0.40————
0.46–0.480.32–0.40
——
0.38—
0.38—
0.46——
0.35—
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Chapter 7 Outline
Figure 7.1 Outline of the topics described in Chapter 7
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Structure ofPolymer
Molecules
Figure 7.2 Basic structure of polymer molecules: (a) ethylene molecule; (b)polyethylene, a linear chain of many ethylene molecules; © molecular structureof various polymers. These are examples of the basic building blocks forplastics
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Molecular Weight and Degree of Polymerization
Figure 7.3 Effect of molecular weightand degree of polymerization on thestrength and viscosity of polymers.
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Polymer Chains
Figure 7.4 Schematicillustration of polymer chains.(a) Linear structure--thermoplastics such asacrylics, nylons, polyethylene,and polyvinyl chloride havelinear structures. (b) Branchedstructure, such as inpolyethylene. (c) Cross-linkedstructure--many rubbers orelastomers have this structure,and the vulcanization of rubberproduces this structure. (d)Network structure, which isbasically highly cross-linked--examples are thermosettingplastics, such as epoxies andphenolics.
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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.
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Crystallinity
Figure 7.6 Amorphousand crystalline regions ina polymer. The crystallineregion (crystallite) has anorderly arrangement ofmolecules. The higher thecrystallinity, the harder,stiffer, and less ductile thepolymer.
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Specific Volume as a Function of Temperature
Figure 7.7 Specific volume of polymersas a function of temperature. Amorphouspolymers, such as acrylic andpolycarbonate, have a glass-transitiontemperature, Tg, but do not have a specificmelting point, Tm. Partly crystallinepolymers, such as polyethylene andnylons, contract sharply while passingthrough their melting temperatures duringcooling.
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Glass-Transition and Melting Temperatures ofSome Polymers
TABLE 7.2Material Tg (°C) Tm (°C)Nylon 6,6PolycarbonatePolyesterPolyethylene
High densityLow density
PolymethylmethacrylatePolypropylenePolystyrenePolytetrafluoroethylenePolyvinyl chlorideRubber
5715073
–90–110105–14100–9087–73
265265265
137115—176239327212—
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Behavior of Plastics
Figure 7.8 General terminology describingthe behavior of three types of plastics. PTFE(polytetrafluoroethylene) has Teflon as itstrade name. Source: R. L. E. Brown.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 7-12
Temperature Effects
Figure 7.9 Effect of temperature on the stress-straincurve for cellulose acetate, a thermoplastic. Note thelarge drop in strength and the large increase inductility with a relatively small increase intemperature. Source: After T. S. Carswell and H. K.Nason. Figure 7.10 Effect of temperature on the impact
strength of various plastics. Small changes intemperature can have a significant effect on impactstrength. Source: P. C. Powell.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 7-13
Elongation
(a) (b) Figure 7.11 (a) Load-elongation curve forpolycarbonate, athermoplastic. Source: R. P.Kambour and R. E.Robertson. (b) High-densitypolyethylene tensile-testspecimen, showing uniformelongation (the long, narrowregion in the specimen).
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 7-14
General Recommendations for Plastic Products
TABLE 7.3Design requirement Applications PlasticsMechanical strength Gears, cams, rollers, valves, fan
blades, impellers, pistonsAcetal, nylon, phenolic,polycarbonate
Functional and decorative Handles, knobs, camera andbattery cases, trim moldings, pipefittings
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-processingequipment, laboratory hardware
Acrylic, polycarbonate,polystyrene, polysulfone
Wear resistance Gears, wear strips and liners,bearings, bushings, roller-skatewheels
Acetal, nylon, phenolic,polyimide, polyurethane,ultrahigh molecular weightpolyethylene
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 7-15
Load-Elongation Curve for Rubber
Figure 7.12 Typical load-elongationcurve for rubbers. The clockwise lop,indicating the loading and theunloading paths, displays the hysteresisloss. Hysteresis gives rubbers thecapacity to dissipate energy, dampvibraion, and absorb shock loading, asis necessary in automobile tires and invibration dampers placed undermachinery.
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CHAPTER 8
Ceramics, Graphite, and Diamond:Structure, General Properties, and
Applications
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Examples of Ceramics
(a) (b)
Figure 8.1 A variety of ceramic components. (a) High-strength alumina for high-temperatureapplications. (b) Gas-turbine rotors made of silicon nitride. Source: Wesgo Div., GTE.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 8-3
Types andGeneral
Characteristicsof Ceramics
TABLE 8.1Type General CharacteristicsOxide 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.
CarbidesTungsten 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 abrasivesand cutting tools.
Titanium nitride Gold in color; used as coatings because of low frictionalcharacteristics.
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-temperaturenonstructural applications.
Glasses Contain at least 50 percent silica; amorphous structures; severaltypes 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 thermalconductivity; good thermal shock resistance.
Diamond Hardest substance known; available as single crystal orpolycrystalline form; used as cutting tools and abrasives and as diesfor fine wire drawing.
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Properties of Various Ceramics at RoomTemperature
TABLE 8.2
Material Symbol
Transverserupturestrength(MPa)
Compressivestrength(MPa)
Elasticmodulus
(GPa)Hardness
(HK)Poisson’sratio (ν)
Density(kg/m3)
Aluminumoxide
Al2O3 140–240 1000–2900 310–410 2000–3000 0.26 4000–4500
Cubic boronnitride
CBN 725 7000 850 4000–5000 — 3480
Diamond — 1400 7000 830–1000 7000–8000 — 3500Silica, fused SiO2 — 1300 70 550 0.25 —Siliconcarbide
SiC 100–750 700–3500 240–480 2100–3000 0.14 3100
Siliconnitride
Si3 N4 480–600 — 300–310 2000–2500 0.24 3300
Titaniumcarbide
TiC 1400–1900 3100–3850 310–410 1800–3200 — 5500–5800
Tungstencarbide
WC 1030–2600 4100–5900 520–700 1800–2400 — 10,000–15,000
Partiallystabilizedzirconia
PSZ 620 — 200 1100 0.30 5800
Note: These properties vary widely depending on the condition of the material.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 8-5
Properties of Various Glasses
TABLE 8.3Soda-lime
glassLead glass Borosilicate
glass96 Percent
silicaFusedsilica
Density High Highest Medium Low LowestStrength Low Low Moderate High HighestResistance to thermal
shockLow Low Good Better Best
Electrical resistivity Moderate Best Good Good GoodHot workability Good Best Fair Poor PoorestHeat treatability Good Good Poor None NoneChemical resistance Poor Fair Good Better BestImpact-abrasion
resistanceFair Poor Good Good Best
Ultraviolet-lighttransmission
Poor Poor Fair Good Good
Relative cost Lowest Low Medium High Highest
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Graphite Components
Figure 8.2 Variousengineeringcomponents made ofgraphite. Source: PocoGraphite, Inc., a UnocalCo.
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CHAPTER 9
Composite Materials: Structure, GeneralProperties, and Applications
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Application of Advanced Composite Materials
Figure 9.1Application ofadvancedcompositematerials inBoeing 757-200commercialaircraft. Source:BoeingCommercialAirplaneCompany.
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Methods of Reinforcing Plastics
Figure 9.2 Schematicillustration of methodsof reinforcing plastics(matrix) with (a)particles, and (b) shortor long fibers orflakes. The four layersof continuous fibers inillustration (c) areassembled into alaminate structure.
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Types and General Characteristics ofComposite Materials
TABLE 9.1Material CharacteristicsFibers 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.
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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 widerange of specific strengths and stiffnesses available.
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Typical Properties of Reinforcing Fibers
TABLE 9.2
Type
Tensilestrength(MPa)
Elasticmodulus
(GPa)Density( kg/m
3) Relative cost
Boron 3500 380 2600 HighestCarbon High strength 3000 275 1900 Low High modulus 2000 415 1900 LowGlass E type 3500 73 2480 Lowest S type 4600 85 2540 LowestKevlar 29 2800 62 1440 High 49 2800 117 1440 HighNote: These properties vary significantly depending on the material and method of preparation.
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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 boronfiber-reinforced composite material.
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Effect of Fiber Type on Fiber-Reinforced Nylon
Figure 9.5 The effectof type of fiber onvarious properties offiber-reinforced nylon(6,6). Source: NASA.
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Fracture Surfaces of Fiber-Reinforced EpoxyComposites
(a) (b)
Figure 9.6 (a) Fracture surface of glass-fiber reinforced epoxy composite. The fibers are10 µm (400 µin.) in diameter and have random orientation. (b) Fracture surface of agraphite-fiber reinforced epoxy composite. The fibers, 9 µm-11 µm in diameter, are inbundles and are all aligned in the same direction. Source: L. J. Broutman.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 7-10
Tensile Strength of Glass-Reinforced Polyester
Figure 9.7 The tensile strengthof glass-reinforced polyester as afunction of fiber content andfiber direction in the matrix.Source: R. M. Ogorkiewicz, TheEngineering Properties ofPlastics. Oxford: OxfordUniversity Press, 1977.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 7-11
Example of Advanced Materials Construction
Figure 9.8 Cross-section of acomposite sailboard, an exampleof advanced materialsconstruction. Source: K.Easterling, Tomorrow’s Materials(2d ed.), p. 133. Institute ofMetals, 1990.
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Metal-Matrix Composite Materials andApplications
TABLE 9.3Fiber Matrix ApplicationsGraphite Aluminum
MagnesiumLeadCopper
Satellite, missile, and helicopter structuresSpace and satellite structuresStorage-battery platesElectrical contacts and bearings
Boron AluminumMagnesiumTitanium
Compressor blades and structural supportsAntenna structuresJet-engine fan blades
Alumina AluminumLeadMagnesium
Superconductor restraints in fission power reactorsStorage-battery platesHelicopter transmission structures
Silicon carbide Aluminum, titaniumSuperalloy (cobalt-base)
High-temperature structuresHigh-temperature engine components
Molybdenum, tungsten Superalloy High-temperature engine components
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CHAPTER 10
Fundamentals of Metal-Casting
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Cast Structures of Metals
Figure 10.1 Schematic illustration ofthree cast structures of metalssolidified in a square mold: (a) puremetals; (b) solid-solution alloys; and(c) structure obtained by usingnucleating agents. Source: G. W.Form, J. F. Wallace, J. L. Walker, andA. Cibula.
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Preferred Texture Development
Figure 10.2 Development of a preferred texture at a cool mold wall. Note that onlyfavorably oriented grains grow away from the surface of the mold.
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Alloy Solidification
Figure 10.3 Schematicillustration of alloysolidification andtemperaturedistribution in thesolidifying metal.Note the formation ofdendrites in the mushyzone.
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Solidification Patterns
Figure 10.4 (a) Solidification patterns for gray cast iron in a 180-mm (7-in.) square casting. Note thatafter 11 min. of cooling, dendrites reach each other, but the casting is still mushy throughout. It takesabout two hours for this casting to solidify completely. (b) Solidification of carbon steels in sand andchill (metal) molds. Note the difference in solidification patterns as the carbon content increases.Source: H. F. Bishop and W. S. Pellini.
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Cast Structures
Figure 10.5Schematicillustration of threebasic types of caststructures: (a)columnar dendritic;(b) equiaxeddendritic; and (c)equiaxednondendritic.Source: D. Apelian.
Figure 10.6 Schematic illustration of cast structuresin (a) plane front, single phase, and (b) plane front,two phase. Source: D. Apelian.
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Riser-Gated Casting
Figure 10.7 Schematic illustrationof a typical riser-gated casting.Risers serve as reservoirs,supplying molten metal to thecasting as it shrinks duringsolidification. See also Fig. 11.4Source: American Foundrymen’sSociety.
Kalpakjian • SchmidManufacturing Engineering and Technology © 2001 Prentice-Hall Page 10-8
Fluidity Test
Figure 10.8 A test method for fluidity usinga spiral mold. The fluidity index is the lengthof the solidified metal in the spiral passage.The greater the length of the solidified metal,the greater is its fluidity.
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Temperature Distribution
Figure 10.9 Temperaturedistribution at the interface of themold wall and the liquid metalduring solidification of metals incasting.
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Solidification Time
Figure 10.10 Solidified skin on asteel casting. The remainingmolten metal is poured out at thetimes indicated in the figure.Hollow ornamental and decorativeobjects are made by a processcalled slush casting, which is basedon this principle. Source: H. F.Taylor, J. Wulff, and M. C.Flemings.
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Solidification Contraction for Various CastMetals
TABLE 10.1
Metal or alloy
Volumetricsolidification
contraction (%) Metal or alloy
Volumetricsolidification
contraction (%)Aluminum 6.6 70%Cu–30%Zn 4.5Al–4.5%Cu 6.3 90%Cu–10%Al 4Al–12%Si 3.8 Gray iron Expansion to 2.5Carbon steel 2.5–3 Magnesium 4.21% carbon steel 4 White iron 4–5.5Copper 4.9 Zinc 6.5Source: After R. A. Flinn.
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Hot Tears
Figure 10.11 Examples of hot tears in castings. These defects occur becausethe casting cannot shrink freely during cooling, owing to constraints invarious portions of the molds and cores. Exothermic (heat-producing)compounds may be used (as exothermic padding) to control cooling at criticalsections to avoid hot tearing.
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Casting DefectsFigure 10.12 Examples of common defects in castings. These defects can be minimized or eliminated byproper design and preparation of molds and control of pouring procedures. Source: J. Datsko.
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Internal and External Chills
Figure 10.13Various types of(a) internal and(b) external chills(dark areas atcorners), used incastings toeliminate porositycaused byshrinkage. Chillsare placed inregions wherethere is a largervolume of metals,as shown in (c).
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Solubility of Hydrogen in Aluminum
Figure 10.14 Solubility of hydrogen inaluminum. Note the sharp decrease insolubility as the molten metal begins tosolidify.
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