Chapter 3: Solid Materials Iron is taken from the earth and copper is smelted from ore. Man puts an end to the darkness; he searches the farthest recesses for ore in the darkness. The Bible (Job 28:2-3) Image: Iron flows from a blast furnace. Source: American Iron and Steel Institute. ©1998 McGraw-Hill Hamrock, Jacobson and Schmid Ductile Tension Test Specimens Figure 3.1 Ductile material from a standard tensile test apparatus. (a) Necking; (b) failure. ©1998 McGraw-Hill text reference: Figure 3.1, page 90 Hamrock, Jacobson and Schmid Brittle Tension Test Specimen Figure 3.2 Failure of a brittle material from a standard tesile test apparatus. ©1998 McGraw-Hill text reference: Figure 3.2, page 91 Hamrock, Jacobson and Schmid Strength/Density Comparison Figure 3.3 Strength/density for various materials. ©1998 McGraw-Hill text reference: Figure 3.3, page 94 Hamrock, Jacobson and Schmid Fiber Reinforced Composite Figure 3.4 Cross section of fiber reinforced composite material. ©1998 McGraw-Hill text reference: Figure 3.4, page 95 Hamrock, Jacobson and Schmid Ductile - diagram Figure 3.5 Stress-strain diagram for a ductile material. ©1998 McGraw-Hill text reference: Figure 3.5, , page 96 Hamrock, Jacobson and Schmid Yield Strength Definition Figure 3.6 Typical stress-strain behavior for ductile metal showing elastic and plastic deformations and yield strength Sy. ©1998 McGraw-Hill text reference: Figure 3.6, page 97 Hamrock, Jacobson and Schmid Brittle and Ductile Metal Comparison Figure 3.7 Typical tensile stress-strain diagrams for brittle and ductile metals loaded to fracture. ©1998 McGraw-Hill text reference: Figure 3.7, page 98 Hamrock, Jacobson and Schmid Stress-Strain Diagram for a Ceramic Figure 3.8 Stress-strain diagram for a ceramic in tension and in compression. ©1998 McGraw-Hill text reference: Figure 3.8, page 99 Hamrock, Jacobson and Schmid Composite Bar Figure 3.9 Bending strength of bar used in Example 3.6. ©1998 McGraw-Hill text reference: Figure 3.9, page 100 Hamrock, Jacobson and Schmid Stress-Strain Diagram for Polymers Figure 3.10 Stress-strain diagram for polymer below, at, and above its glass transition temperature Tg. ©1998 McGraw-Hill text reference: Figure 3.10, page 101 Hamrock, Jacobson and Schmid Density of Various Materials Figure 3.11 Density for various metals, polymers and ceramics at room temperature (20°C, 68°F) [From ESDU (1984)]. ©1998 McGraw-Hill text reference: Figure 3.11, page 102 Hamrock, Jacobson and Schmid Material kg/m3 Dens ity, Metals Aluminum and its alloysa 2.7 x 103 Aluminum tin 3.1 x 103 Babbitt, lead-based white metal 10.1 x 103 Babbitt, tin-based white metal 7.4 x 103 Brasses 8.6 x 103 Bronze, aluminum 7.5 x 103 Bronze, leaded 8.9 x 103 b Bronze, phosphor (cast) 8.7 x 103 Bronze, porous 6.4 x 103 Copper 8.9 x 103 Copper lead 9.5 x 103 Iron, cast 7.4 x 103 Iron, porous 6.1 x 103 Iron, wrought 7.8 x 103 Magnesium alloys 1.8 x 103 c Steels 7.8 x 103 Zinc Alloys 6.7 x 103 Polymers Acetal (polyformaldehyde) 1.4 x 103 Nylons (polyamides) 1.14 x 103 Polyethylene, high density 0.95 x 103 Phenol formaldehyde 1.3 x 103 d Rubber, natural 1.0 x 103 Rubber, silicone 1.8 x 103 Ceramics Alumina (Al2 O3 ) 3.9 x 103 Graphite, high strength 1.7 x 103 Silicon carbide (SiC) 2.9 x 103 Silicon nitride (Si3 N4 ) 3.2 x 103 a Structural alloys b Bar stock typically 8.8 x 103 kg/m3 (0.03lbm/in3.) c Excluding “refractory” steels d “Mechanical” rubber ©1998 McGraw-Hill lbm/in3 0.097 0.11 0.36 0.27 0.31 0.27 0.32 0.31 0.23 0.32 0.34 0.27 0.22 0.28 0.065 0.28 0.24 0.051 0.041 0.034 0.047 0.036 0.065 Density for Various Materials Table 3.1 Density for various metals, polymers, and ceramics at room temperature (20°C; 68°F). [From ESDU (1984)] 0.14 0.061 0.10 0.12 text reference: Table 3.1, page 103 Hamrock, Jacobson and Schmid Elastic Modulus for Various Materials Figure 3.12 Modulus of elasticity for various metals, polymers, and ceramics at room temperature (20°C, 68°F) [From ESDU (1984)]. ©1998 McGraw-Hill text reference: Figure 3.12, page 105 Hamrock, Jacobson and Schmid Material Modulus of Elas ticity, E GPa Mps i Metals Aluminum 62 Aluminum alloysa 70 Aluminum tin 63 Babbitt, lead-based white metal 29 Babbitt, tin-based white metal 52 Brasses 100 Bronze, aluminum 117 Bronze, leaded 97 Bronze, phosphor 110 Bronze, porous 60 Copper 124 Iron, grey cast 109 Iron, malleable cast 170 Iron, spheroidal graphiteb 159 Iron, porous 80 Iron, wrought 170 Magnesium alloys 41 Steel, low alloys 196 Steel, medium and high alloys 200 Steel, stainlessc 193 Steel, high speed 212 Zinc alloysd 50 Polymers Acetal (polyformaldehyde) 2.7 Nylons (polyamides) 1.9 Polyethylene, high density 0.9 Phenol formaldehydee 7.0 Rubber, naturalf 0.004 Ceramics Alumina (Al2 O3 ) 390 Graphite 27 Cemented carbides 450 Silicon carbide (SiC) 450 Silicon nitride (Si3 N4 ) 314 a Structural alloys b For bearings c Precipitation-hardened alloys up to 211 Gpa (30 Mpsi). d Some alloys up to 96 Gpa (14 Mpsi). e Filled f 2.5%-carbon-black “mechanical” rubber. ©1998 McGraw-Hill 9.0 10.2 9.1 4.2 7.5 14.5 17.0 14.1 16.0 8.7 18.0 15.8 24.7 23.1 11.6 24.7 5.9 28.4 29.0 28.0 30.7 7.3 0.39 0.28 0.13 1.02 0.0006 Elastic Modulus for Various Materials Figure 3.12 Modulus of elasticity for various metals, polymers, and ceramics at room temperature (20°C; 68°F). [From ESDU (1984)] 56.6 3.9 65.3 65.3 45.5 text reference: Table 3.2, page 106 Hamrock, Jacobson and Schmid Material Metals Aluminum and its alloysa Aluminum tin Babbitt, lead-based white metal Babbitt, tin-based white metal Brasses Bronze Bronze, porous Copper Copper lead Iron, cast Iron, porous Iron, wrought Magnesium alloys Steels Zinc alloys Polymers Acetal (polyformaldehyde) Nylons (polyamides) Polyethylene, high density Phenol formaldehydee Rubber Ceramics Alumina (Al2 O3 ) Graphite, high strength Cemented carbides Silicon carbide (SiC) Silicon nitride (Si3 N4 ) a Structural alloys ©1998 McGraw-Hill Pois s on’s ratio, 0.33 ------0.33 0.33 0.22 0.33 --0.26 0.20 0.30 0.33 0.30 0.27 --0.40 0.35 --0.50 Poisson’s Ratio for Various Materials Table 3.3 Poisson’s ratio for various metals, polymers, and ceramics at room temperature (20°C; 68°F). [From ESDU (1984)] 0.28 --0.19 0.19 0.26 text reference: Table 3.3, page 107 Hamrock, Jacobson and Schmid Thermal Condictivity for Various Materials Figure 3.13 Thermal conductivity for various metals, polymers, and ceramics at room temperature (20°C, 68°F). [From ESDU (1984)]. ©1998 McGraw-Hill text reference: Figure 3.13, page 113 Hamrock, Jacobson and Schmid Material Metals Aluminum Aluminum alloys, casta Aluminum alloys, siliconb Aluminum alloys, wroughtc Aluminum tin Babbitt, lead-based white metal Babbitt, tin-based white metal Brassesa Bronze, aluminuma Bronze, leaded Bronze, phosphor (cast)d Bronze, porous Coppera Copper lead Iron, grey cast Iron, spheroidal graphite Iron, porous Iron, wrought Magnesium alloys Steel, low alloyse Steel, medium Steel, stainlessf Zinc alloys Polymers Acetal (polyformaldehyde) Nylons (polyamides) Polyethylene, high density Phenol formaldehydee Rubber, naturalf Ceramics Alumina (Al2 O3 )g Graphite, high strength Silicon carbide (SiC) Silicon nitride (Si3 N4 ) a At 100°C b At 100°C (~150 W/m-°C at 25°C) c 20 to 100°C d Bar stock typically 69 W/m-°C e 20 to 200°C f Typically 22W/m-°C at 200°C g Typically 12W/m-°C at 400°C ©1998 McGraw-Hill Thermal Conductivity, K t W/m-°C Btu/ft-hr°F 209 146 170 151 180 24 56 120 50 47 50 30 170 30 50 30 28 70 110 35 30 15 110 120 84 98 87 100 14 32 69 29 27 29 17 98 17 29 17 16 40 64 20 17 8.7 64 0.24 0.25 0.5 --1.6 0.14 0.14 0.29 --0.92 25 125 15 --- 14 72 8.6 --- Thermal Conductivity for Various Materials Table 3.4 Thermal conductivity for various metals, polymers, and ceramics at room temperature (20°C; 68°F). [From ESDU(1984)] text reference: Table 3.4, page 114 Hamrock, Jacobson and Schmid Thermal Expansion Coefficient for Various Materials Figure 3.14 Linear thermal expansion coefficient for various metals, polymers, and ceramics applied over temperature range 20 to 200°C (68 to 392°F) [From ESDU (1984)]. ©1998 McGraw-Hill text reference: Figure 3.14, page 115 Hamrock, Jacobson and Schmid Material Metals Aluminum Aluminum alloysa Aluminum tin Babbitt, lead-based white metal Babbitt, tin-based white metal Brasses Bronzes Copper Copper lead Iron, cast Iron, porous Iron, wrought Magnesium alloys Steel, alloyb Steel, stainless Steel, high speed Zinc alloys Polymers Thermoplasticsc Thermosetsd Acetal (polyformaldehyde) Nylons (polyamides) Polyethylene, high density Phenol formaldehydee Rubber, naturalf Rubber, nitrileg Rubber, silicone Ceramics Alumina (Al2 O3 )h Graphite, high strength Silicon carbide (SiC) Silicon nitride (Si3 N4 ) a Structural alloys b Cast alloys can be up to 15 x 10-6 /(°C) c Typical bearing materials d 25 x 10-6 (°C)-1 to 80 x 10-6 (°C)-1 when reinforced e Mineral filled f Fillers can reduce coefficients g Varies with composition h 0 to 200°C ©1998 McGraw-Hill Linear Thermal Expans ion Coefficient, a (°C) -1 (°F) -1 23 x 10-6 24 x 10-6 24 x 10-6 20 x 10-6 23 x 10-6 19 x 10-6 18 x 10-6 18 x 10-6 18 x 10-6 11 x 10-6 12 x 10-6 12 x 10-6 27 x 10-6 11 x 10-6 17 x 10-6 11 x 10-6 27 x 10-6 12.8 x 10-6 13.3 x 10-6 13.3 x 10-6 11 x 10-6 13 x 10-6 10.6 x 10-6 10.0 x 10-6 10.0 x 10-6 10.0 x 10-6 6.1 x 10-6 6.7 x 10-6 6.7 x 10-6 15 x 10-6 6.1 x 10-6 9.5 x 10-6 6.1 x 10-6 15 x 10-6 (60-100) x 10-6 (10-80) x 10-6 90 x 10-6 100 x 10-6 126 x 10-6 (25-40) x 10-6 (80-120) x 10-6 34 x 10-6 57 x 10-6 (33-56) x 10-6 (6-44) x 10-6 50 x 10-6 56 x 10-6 70 x 10-6 (14-22) x 10-6 (44-67) x 10-6 62 x 10-6 103 x 10-6 5.0 x 10-6 1.4-4.0 x 10-6 4.3 x 10-6 3.2 x 10-6 2.8 x 10-6 0.8-2.2 x 10-6 2.4 x 10-6 1.8 x 10-6 Linear Thermal Expansion Coefficient for Various Materials Table 3.5 Linear thermal expansion coefficient for various metals, polymers and ceramics at room temperature (20°C; 68°F). [From ESDU (1984)] text reference: Table 3.5, page 116 Hamrock, Jacobson and Schmid Specfic Heat Capacity for Various Materials Figure 3.15 Specific heat capacity for various metals, polymers, and ceramics at room temperature (20°C; 68°F) [From ESDU (1984)]. ©1998 McGraw-Hill text reference: Figure 3.15, page 117 Hamrock, Jacobson and Schmid Specific Heat Capacity for Various Materials Material S pecific Heat Capacity, C p kJ/kg-°C Btu/lb°F Metals Aluminum and its alloys 0.9 Aluminum tin 0.96 Babbitt, lead-based white metal 0.15 Babbitt, tin-based white metal 0.21 Brasses 0.39 Bronzes 0.38 Coppera 0.38 Copper lead 0.32 Iron, cast 0.42 Iron, porous 0.46 Iron, wrought 0.46 Magnesium alloys 1.0 Steelsb 0.45 Zinc alloys 0.4 Polymers Thermoplastics 1.4 Thermosets --Rubber, natural 2.0 Ceramics Alumina (Al2 O3 )h --Graphite 0.8 Cemented Carbides 0.7 Silicon carbide (SiC) --Silicon nitride (Si3 N4 ) --a Aluminum bronze up to 0.48 kJ/kg-°C (0.12 Btu/lbm-°F) b Rising to 0.55 kJ/kg-°C (0.13 Btu/lbm-°F) at 200°C (392 °F) 0.22 0.23 0.036 0.05 0.093 0.091 0.091 0.076 0.10 0.11 0.11 0.24 0.11 0.096 0.33 --0.48 --0.2 0.17 ----- Table 3.6 Specific heat capacity for various metals, polymer, and ceramics at room temperature (20°C; 68°F). [From ESDU (1984)] ©1998 McGraw-Hill text reference: Table 3.6, page 118 Hamrock, Jacobson and Schmid Rigid Beam Assembly Figure 3.16 Rigid beam assembly used in Example 3.12. ©1998 McGraw-Hill text reference: Figure 3.16, page 120 Hamrock, Jacobson and Schmid Elastic Modulus vs. Density Figure 3.17 Modulus of Elasticity plotted against density. The heavy envelopes enclose data for a given class of material. The diagonal contours show the longitudinal wave velocity. The guidelines of constant E/, E1/2/ , and E1/3/ allow selection of materials for minimum weight, deflection-limited design. [From Ashby (1992)]. ©1998 McGraw-Hill text reference: Figure 3.17, page 122 Hamrock, Jacobson and Schmid Material Classes Clas s Enginering alloys (the metals and alloys of engineering) Engineering polymers (the thermoplastics and thermosets of engineering) Engineering ceramics (fine ceramics capable of load-bearing application) ©1998 McGraw-Hill Members Aluminum alloys Copper alloys Lead alloys Magnesium alloys Molybdenum alloys Nickel alloys Steels Tin alloys Titanium alloys Tungsten alloys Zinc alloys Epoxies Melamines Polycarbonate Polyester Polyethylene, high density Polyethylene, low density Polyformaldehyde Polymethylmethacrylate Polypropylene Polytetrafluoroethylene Polyvinyl chloride Alumina Diamond Sialons Silicon carbide Silicon nitride Zirconia S hort name Al alloys Cu alloys Lead alloys Mg alloys Mo alloys Ni alloys Steels Tin alloys Ti alloys W alloys Zn alloys EP MEL PC PEST HDPE LDPE PF PMMA PP PTFE PVC Al2 O3 C Sialons SiC Si3 N4 ZrO2 text reference: Table 3.7, page 123 Table 3.7 Material classes and members and short names of each member. [From Ashby (1992)]. Hamrock, Jacobson and Schmid Material Classes (cont.) Clas s Engineering compos ites (the composites of engineering practice) A distinction is drawn between the properties of a ply (uniply) and a laminate (laminates) Porous ceramics (traditional ceramics, cements, rocks, and minerals Glas s es (ordinary silicate glass) Woods Separate clusters describe properties parallel to the grain and normal to it and wood products Elastomers (natural and artificial rubbers) Polymer foams (foamed polymers of engineering) ©1998 McGraw-Hill Members Carbon-fiber reinforced polymer Glass-fiber reinforced polymer Kevlar-fiber reinforced polymer S hort name CFRP Brick Cement Common rocks Concrete Porcelain Pottery Borosilicate glass Soda glass Silica Ash Balsa Fir Oak Pine Wood products (ply, etc.) Natural rubber Hard butyl rubber Polyurethanes Silicone rubber Soft butyl rubber Cork Polyester Polystyrene Polyurethane Brick Cement Rocks Concrete Pcln Pot B-glass Na-glass SiO2 Ash Balsa Fir Oak Pine Wood products Rubber Hard butyl PU Silicone Soft butyl Cork PEST PS PU GFRP KFRP text reference: Table 3.7, page 123 Table 3.7 Material classes and members and short names of each member. [From Ashby (1992)]. Hamrock, Jacobson and Schmid Strength vs. Density Figure 3.18 Strength plotted against density (yield strength for metals and polymers, compressive strength for ceramics, tear strength for elastomers, and tensile strength for composites). The guidelines of S/, S2/3/, and S1/2/ allow selection of materials for minimum-weight, yield-limited design. [From Ashby (1992)]. ©1998 McGraw-Hill text reference: Figure 3.18, page 125 Hamrock, Jacobson and Schmid Elastic Modulus vs. Strength Figure 3.19 Modulus of elasticity plotted against strength. The design guidelines help with the selection of materials for such machine elements as springs, knife-edges, diaphragms, and hinges. [From Ashby (1992)]. ©1998 McGraw-Hill text reference: Figure 3.19, page 127 Hamrock, Jacobson and Schmid Wear Constant vs. Limiting Pressure Figure 3.20 Archard wear constant plotted against limiting pressure. [From Ashby (1992)]. ©1998 McGraw-Hill text reference: Figure 3.20, page 129 Hamrock, Jacobson and Schmid Elastic Modulus vs. Cost x Density Figure 3.21 Modulus of elasticity plotted against cost times density. The reference lines help with selection of materials for machine elements. [From Ashby (1992)]. ©1998 McGraw-Hill text reference: Figure 3.21, page 131 Hamrock, Jacobson and Schmid