°F) for 2 h and slowly cooling. However, such treatment causes some loss of strength in AZ31B-H24 sheet products. If distortion of part is observed after rough machining, the cutting tool should be inspected to ensure that it is sharp and properly ground. If so, the size of cut should be decreased. With complex parts or parts machined to extremely close tolerances, it may be advisable to stress relieve or, if time permits, to store parts for 2 or 3 days between rough machining and finishing. Design and Weight Reduction By substituting magnesium alloys for heavier metals such as steel and aluminum alloys, many structural parts can be substantially reduced in weight with little or no redesign. This is possible because manufacturing limitations make many parts heavier than necessary. For example, for successful filling of the mold, a casting may require a minimum wall thickness greater than that dictated by service requirements and the strength of the metal used. Similarly, forgings and extrusions sometimes must be made thicker than necessary, and the light weight of magnesium can be used to advantage. In many instances, a casting, forging, or extrusion for which magnesium is substituted for a heavier metal can have adequate strength with no increase in wall thickness. In other parts, substitution of magnesium may require greater wall thickness, and substantial redesign may be necessary in order to realize maximum weight savings. Because strength and stiffness in bending of many structural sections increase approximately as the square and cube of the section depth, respectively, it is possible to obtain large increases in strength and stiffness with moderate increases in depth and cross-sectional area. When such increases in depth are permissible, it usually is economical to redesign the part for magnesium. The greater bulk of the redesigned part reduces local instability, and although the saving in weight is less than maximum, the reduction in instability allows design simplification and thus reduces manufacturing costs. The room-temperature thickness, strength, stiffness, and weight of magnesium alloys are compared with those of aluminum alloys and steel in Table 27. Bending strength is defined as the product of yield strength and section modulus. Table 27 Relative bending strength, stiffness, and weight of selected structural metals Material Thickness Bending strength Stiffness Weight For equal thickness 1025 steel 100 100.0 100.0 100.0 6061-T6 aluminum sheet and extrusions 100 97.2 34.5 34.5 AZ31B magnesium extrusions 100 47.2 22.4 22.5 ZK60A-T5 magnesium extrusions 100 88.9 22.4 22.5 AZ31B-H24 magnesium sheet 100 73.4 22.4 22.5 For equal bending strength 1025 steel 100 100 100.0 100.0 6061-T6 aluminum sheet and extrusions 101 100 35.8 34.8 AZ31B magnesium extrusions 146 100 69.2 32.9 ZK60A-T5 magnesium extrusions 106 100 26.7 23.9 AZ31B-H24 magnesium sheet 117 100 35.6 26.3 For equal stiffness 1025 steel 100 100 100 100.0 6061-T6 aluminum sheet and extrusions 143 199 100 49.2 AZ31B magnesium extrusions 165 129 100 37.2 ZK60A-T5 magnesium extrusions 165 242 100 37.2 AZ31B-H24 magnesium sheet 165 200 100 37.2 For equal weight 1025 steel 100 100 100 100 6061-T6 aluminum sheet and extrusions 290 817 841 100 AZ31B magnesium extrusions 444 930 1962 100 ZK60A-T5 magnesium extrusions 444 1753 1962 100 AZ31B-H24 magnesium sheet 444 1451 1962 100 Note: Comparison made at room temperature for rectangular beams of constant width with the following minimum yield s trengths: 1025 steel, 250 MPa (36 ksi); 6061- T6 aluminum, 240 MPa (35 ksi); magnesium alloys, average of minimum tensile yield and compressive yield strengths. All comparisons expressed in percent Bending. Rectangular steel, aluminum, and magnesium sections of equal thickness have rigidities in the ratio of their moduli of elasticity. The magnesium section weighs about 63% as much as the aluminum section and about 22% as much as the steel section. The rigidity in bending of a rectangular section is proportional both to the cube of its depth and to its modulus of elasticity. If the section thicknesses of a magnesium section, an aluminum section, and a steel section are adjusted until their rigidities are equal, the magnesium section will weigh about 71% of the aluminum and about 40% of the steel. If the section thickness of the magnesium is increased to about twice that of the steel, the magnesium will be more than 70% more rigid than the steel and less than 50% as heavy. Magnesium supporting its own weight shows no more deflection than other metals under the same conditions. At high temperatures, the difference between short-time ultimate and yield strengths of certain magnesium alloys decreases significantly. Creep properties that depend on time must also be considered in evaluating materials for long- time operation at elevated temperature. Creep-strength values of several magnesium alloys are given in the data compilations in the article "Properties of Magnesium Alloys" in this Volume. Plate Buckling. Structures subjected to compressive loads may be limited in efficiency (load carried versus weight of structure) by buckling at relatively low stresses. A structural index is a valuable aid to designers in the selection of optimum materials for plate structures that are critical in compression loading. A structural index is nondimensional; that is, equivalent designs give the same value of structural index regardless of the size of the actual part. The plate-buckling index is computed from the maximum edge load (P cr ) that will not cause crippling, the width (b) of the plate and a factor, K, determined by the amount of restraint or clamping along the unloaded edges for a simply supported edge, K = 4.0). The formula is: 0,5 ² cr Pk Index b = Using this index, the efficiency of various structural materials can be directly compared for given conditions of loading and structural configuration. For example, the efficiencies of three materials at room temperature and at 260 °C (500 °F) for plate-buckling indexes up to 4000 are shown in Fig. 19. Comparisons are based on typical properties after short-time exposure at temperature. Fig. 19 Effect of plate- buckling index and temperature on the structural efficiency of magnesium, aluminum, and titanium alloys. See text for discussion. A low value of plate-buckling index means either that the critical edge load is low or that the plate is wide, corresponding in either instance to a more lightly stressed structure. As the index value increases, it represents a transition to narrower plates and/or heavier edge loads and, at high values, corresponds to a condition of pure prismatic compression. The ratio of working stress to density is an inverse measure of structural weight the higher the ratio, the lighter the structure. Figure 19 shows the expected advantage in efficiency of the lowest-density magnesium alloy HK31A-H24 over the higher-density aluminum and titanium alloys. This advantage fades as the index increases, and the stress condition moves from elastic buckling toward prismatic compression. Comparison of the two charts shows that the range over which the magnesium alloy is the most efficient of the three alloys (magnesium, aluminum, and titanium) is higher at 260 °C (500 °F) than at room temperature. Wrought Magnesium Alloys AZ10A Specifications UNS. M11100 Government. Extruded rods, bars, and shapes: QQ-M- 31 Chemical Composition Composition limits. 1.0 to 1.5 Al, 0.2 to 0.6 Zn, 0.2 Mn min, 0.1 Si max, 0.1 Cu max, 0.005 Ni max, 0.005 Fe max, 0.04 Ca max, bal Mg Applications Typical uses. Low-cost extrusion alloy with moderate mechanical properties and high elongation. Used in as- extruded (F) temper Mechanical Properties Tensile properties. See Table 1. Table 1 Typical mechanical properties of AZ10A at room temperature Tensile strength Yield strength Compressive yield strength Size and shape MPa ksi MPa ksi Elongation, % MPa ksi Solid shapes with least dimension up to 6.4 mm (0.025 in.) 240 35 145 21 10 69 10 Solid shapes with least dimension to 6.4 to 38 mm (0.025 to 1.5 in.) 240 35 150 22 10 76 11 Hollow and semihollow shapes 230 33 145 21 8 69 10 Tube (152 mm, or 6 in. OD max) with 0.7 to 6.4 mm (0.028 to 0.25 in.) wall 230 33 145 21 8 69 10 Compressive properties. See Table 1. Poisson's ratio. 0.35 Elastic modulus. Tension, 45 GPa (6.5 × 10 6 psi) Mass Characteristics Density. 1.76 g/cm 3 (0.064 lb/in. 3 ) at 20 °C (68 °F) Thermal Properties Liquidus temperature. 645 °C (1190 °F) Solidus temperature. 630 °C (1170 °F) Coefficient of linear thermal expansion. 26.6 μm/m · K (14.8 μin./in. · °F) at 21 to 204 °C (70 to 400 °F) Thermal conductivity. 110 W/m · K (64 Btu/ft · h · °F) at 20 °C (68 °F) Electrical Properties Electrical resistivity. 64 nΩ · m at 20 °C (68 °F) Fabrication Characteristics Weldability. Good; does not require stress relief after welding AZ21X1 Specifications UNS. M11210 Chemical Composition Composition limits. 1.6 to 2.5 Al, 0.8 to 1.6 Zn, 0.1 to 0.25 Ca, 0.15 Mn max, 0.05 Si max, 0.05 Cu max, 0.005 Fe max, 0.002 Ni max, 0.3 max other, bal Mg Applications Typical uses. Impact-extruded battery anodes. Used in as-extruded (F) temper AZ31B, AZ31C Specifications AMS. AZ31B sheet: O temper, 4357; H24 temper, 4376 ASTM. Sheet: B 90. Extruded rod, bar, shapes, tubing, and wire: B 107, AZ31B forgings: B 91 SAE. AZ31B: J466. Former SAE alloy number: 510 UNS numbers. AZ31B: M11311. AZ31C: M11312 Government. AZ31B: forgings, sheet, and plate, QQ- M-40; extruded bar, rod, and shapes, QQ-M-31B; extruded tubing, WW-T-825B Foreign. Elektron AZ31 (extruded bar and tubing). British: sheet, BS 3370 MAG111; extruded bar and tubing, BS 3373 MAG111. German: DIN 9715 3.5312. French: AFNOR G-A371 Chemical Composition Composition limits of AZ31B. 2.5 to 3.5 Al, 0.20 Mn min, 0.60 to 1.4 Zn, 0.04 Ca max, 0.10 Si max, 0.05 Cu max, 0.005 Ni max, 0.005 Fe max, 0.30 max other (total); bal Mg Composition limits of AZ31C. 2.4 to 3.6 Al, 0.15 Mn min, 0.50 to 1.5 Zn, 0.10 Cu max, 0.03 Ni max, 0.10 Si max, bal Mg Consequence of exceeding impurity limits. Excessive Cu, Ni, or Fe degrades corrosion resistance. Applications Typical uses. AZ31B and AZ31C: forgings and extruded bar, rod, shapes, structural sections, and tubing with moderate mechanical properties and high elongation; AZ31C is the commercial grade, with the same properties as AZ31B but higher impurity limits. AZ31B only: sheet and plate with good formability and strength, high resistance to corrosion, and good weldability. AZ31B and AZ31C are used in the asfabricated (F), annealed (O), and hard-rooled (H24) tempers. Mechanical Properties Tensile properties. See Tables 2 and 3. Table 2 Typical room-temperature mechanical properties of AZ31B Tensile strength Tensile yield strength (a) Hardness Shear strength Compressive yield strength (a) Ultimate bearing strength (d) Bearing yield strength (d) Product form MPa ksi MPa ksi Elongation, % (b) HB (c) HRE MPa ksi MPa ksi MPa ksi MPa ksi Sheet, annealed 255 37 150 22 21 56 67 145 21 110 16 485 70 290 42 Sheet, hard rolled 290 42 220 32 15 73 83 160 23 180 26 495 72 325 47 Extruded bar, rod, and solid shapes 255 37 200 29 12 49 57 130 19 97 14 385 56 230 33 Extruded hollow shapes and tubing 241 35 165 24 16 46 51 . . . . . . 83 12 . . . . . . . . . . . . Forgings 260 38 170 25 15 50 59 130 19 . . . . . . . . . . . . . . . . . . (a) At 0.2% offset. (b) In 50 mm (2 in.). (c) 500 kg load 10 mm ball. (d) 4.75 mm ( 3 16 in.) pin diameter Table 3 Typical tensile properties of AZ31B at various temperatures Testing temperature Tensile strength Yield strength °C °F MPa ksi MPa ksi Elongation in 50 mm (2 in.), % Sheet, hard rolled -80 -112 331 48.0 234 34.0 . . . -27 -18 310 45.0 234 34.0 . . . 21 70 290 42.0 221 32.0 15 100 212 207 30.0 145 21.0 30 150 300 152 22.0 90 13.0 45 200 400 103 15.0 59 8.5 55 260 500 76 11.0 31 4.5 75 315 600 41 6.0 21 3.0 125 370 700 28 4.0 14 2.0 140 Extrusions, as fabricated -185 -300 434 63.0 338 49.0 6.0 -130 200 359 52.0 303 44.0 7.5 -73 -100 314 45.5 262 38.0 9.5 -18 0 283 41.0 228 33.0 12.5 21 70 262 38.0 200 29.0 15.0 93 200 238 34.5 148 21.5 23.5 120 250 217 31.5 117 17.0 29.5 150 300 179 26.0 100 14.5 37.5 Shear strength. See Table 2. Compressive yield strength. See Table 2. Bearing properties. See Table 2. Hardness: See Table 2. Poisson's ratio. 0.35 Elastic modulus. Tension, 45 GPa (6.5 × 10 6 psi); shear, 17 GPa (2.4 × 10 6 psi) Impact Strength. Forgings and extruded bar, rod, and solid shapes: Charpy V-notch, 4.3 J (3.2 ft · lbf) Directional properties. See Table 4. Mass Characteristics Density: 1.77 g/cm 3 (0.064 lb/in. 3 ) at 20 °C (68 °F) Thermal Properties Liquidus temperature. 630 °C (1170 °F) Solidus temperature. 605 °C (1120 °F) Coefficient of linear thermal expansion. 26 μm/m · K (14 μin./in. · °F) Specific heat versus temperature. C p = 0.2441 + 0.000105T - 2783T -2 Latent heat of fusion. 330 to 347 kJ/kg (142 to 149 Btu/lb) Thermal conductivity. 96 W/m · K (56 Btu/ft · h · °F) at 100 to 300 °C (212 to 572 °F) Electrical Properties Electrical conductivity. 18.5% IACS Electrical resistivity. 92 nΩ · m at 20 °C (68 °F) Electrolytic solution potential. 1.59 V versus saturated calomel electrode Fabrication Characteristics Weldability. Gas-shielded arc welding with AZ61A or AZ92A rod (AZ61A preferred), excellent; stress relief required. Resistance welding, excellent Recrystallization temperature. Recrystallizes after 1 h at 205 °C (400 °F) following 15% cold work Annealing temperature. 345 °C (650 °F) Hot-working temperature. 230 to 425 °C (450 to 800 °F) AZ61A Specifications AMS. Extrusions: 4350. Forgings: 4358 ASTM. Extrusions: B 107. Forgings: B 91 SAE. J466. Former SAE alloy numbers: 520 (extrusions) and 531 (forgings) UNS number. M11610 Government. Extruded bar, rod, and shapes: QQ-M- 31B. Extruded tubing: WW-T-825A. Forgings: QQ-M- 40B Foreign. Elektron AZ61 (extruded bar, sections, and tubing). British: extruded bar, sections, and tubing, BS 3373 MAG121; forgings, BS 3372 MAG121. German: DIN 9715 3.5612; castings, DIN 1729 3.5612. French: AFNOR G-A6Z1 Chemical Composition Table 4 Typical directional properties of AZ31B Tensile strength Yield strength Condition MPa ksi MPa ksi Elongation % (a) Parallel to rolling direction Annealed 255 37 150 22 21 Hard rolled 290 42 220 32 15 Perpendicular to rolling direction Annealed 270 39 170 25 19 Hard rolled 295 43 235 34 19 (a) In 50 mm (2 in.) Composition limits. 5.8 to 7.2 Al, 0.15 Mn min, 0.40 to 1.5 Zn. 0.10 Si max, 0.05 Cu max, 0.005 Ni max, 0.005 Fe max, 0.30 max other (total), bal Mg Consequence of exceeding impurity limits. Excessive Cu, Ni, or Fe degrades corrosion resistance. Applications Typical uses. General-purpose extrusions with good properties and moderate costs, and forgings with good mechanical properties; used in the as-fabricated (F) temper. This alloy is used in sheet form for battery applications only. Mechanical Properties Tensile properties. See Tables 5 and 6. Table 5 Typical room-temperature mechanical properties of AZ61A-F Tensile strength Tensile yield strength (a) Hardness Shear strength Compressive yield strength (a) Ultimate bearing strength (d) Bearing yield strength (d) Form and condition MPa ksi MPa ksi Elongation, % (b) HB (c) HRE MPa ksi MPa ksi MPa ksi MPa ksi Forgings 295 43 180 26 12 55 66 145 21 125 18 . . . . . . . . . . . . Extruded bar, rod, and shapes 305 44 205 30 16 60 72 140 20 130 19 470 68 285 41 Extruded tubing and hollow shapes 285 41 165 24 14 50 60 . . . . . . 110 16 . . . . . . . . . . . . Sheet 305 44 220 32 8 . . . . . . . . . . . . 150 22 . . . . . . . . . . . . (a) At 0.2% offset. (b) In 50 mm (2 in.). (c) 500 kg load, 10 mm ball. (d) 4.75 mm ( 3 16 in.) pin diameter Table 6 Typical properties of AZ61A-F extrusions at various temperatures Temperature Tensile strength Yield strength °C °F MPa ksi MPa ksi Elongation in 50 mm (2 in.), % -185 -300 379 55.0 317 46.0 4 -130 -200 355 51.5 296 43.0 6.5 -73 -100 331 48.0 265 38.5 9.5 -18 0 317 46.0 238 34.5 13 21 70 310 45.0 228 33.0 16 93 200 286 41.5 179 26.0 23 150 300 217 31.5 134 19.5 32 200 400 145 21.0 97 14.0 48.5 315 600 52 7.5 34 5.0 70 Shear strength. See Table 5. Compressive yield strength. See Table 5. Bearing properties. See Table 5. Hardness. See Table 5. Poisson's ratio. 0.35 Elastic modulus. Tension, 45 GPa (6.5 × 10 6 psi); shear, 17 GPa (2.4 × 10 6 psi) Impact strength. Charpy V-notch: forgings, 3 J (2.2 ft · lbf); extruded rod, bar, and shapes, 4.1 J (3.0 ft · lbf) Mass Characteristics Density: 1.8 g/cm 3 (0.065 lb/in. 3 ) at 20 °C (68 °F) Thermal Properties Liquidus temperature. 620 °C (1145 °F) Solidus temperature. 525 °C (975 °F) Incipient melting temperature. 418 °C (785 °F) Coefficient of linear thermal expansion. 26 μm/m · K (14 μin./in. · °F) at 20 °C (68 °F) Specific heat. 1.05 kJ/kg · K (0.25 Btu/lb · °F) at 25 °C (78 °F) Latent heat of fusion. 373 kJ/kg (160 Btu/lb) Thermal conductivity. 80 W/m · K (46 Btu/ft · h · °F) Electrical Properties Electrical conductivity. 11.6% IACS at 20 °C (68 °F) Electrical resistivity. 125 nΩ·m at 20 °C (68 °F) Electrolytic solution potential. 1.58 V versus saturated calomel electrode Fabrication Characteristics Weldability. Gas-shielded arc welding with AZ16A or AZ92A rod (AZ61A preferred), good; stress relief required. Resistance welding, excellent Recrystallization temperature. Recrystallizes after 1 h at 288 °C (550 °F) following 20% cold work Annealing temperature. 345 °C (650 °F) Hot-working temperature. 230 to 400 ° (450 to 750 °F) Hot-shortness temperature. 415 °C (780 °F) [...]... sheet(b) 21 70 235 34 170 25 130 19 8 200 400 125 18 115 17 105 15 30 260 500 110 16 105 15 105 15 25 315 600 97 14 83 12 83 12 15 370 70 0 76 11 55 8 55 8 50 HM21A-T5 forgings(c) 21 70 230 33 140 20 115 17 15 200 400 110 16 90 13 49(d) 315 600 90 13 76 11 37( d) 370 70 0 76 11 55 8 43(d) (a) In 50 mm (2 in.) (b) Under 100-h exposure (c) Rapid heating, except for forging tested at 21 °C ( 170 °F) (d)... 13.3 72 10.5 93 13.5 260 500 55 8.0 48 7. 0 62 9.0 315 600 34 5.0 34 5.0 41 6.0 370 70 0 16 2.3 18 2.6 24 3.5 Fig 6(a) Isochronous stress-strain curves for HM21A-T8 sheet tested at 204, 260, 316, and 371 °C (400, 500, 600, and 70 0 °F) Fig 6(b) Isochronous stress-strain curves for HM21A-T8 sheet tested at 4 27 and 482 °C (800 and 900 °F) Specimens held at test temperature 3 h before testing Electrical Properties. .. ksi MPa ksi MPa ksi 17 48 55 115 17 76 11 350 51 200 29 26 7 54 65 115 17 125 18 395 57 270 39 180 26 12 44 45 125 18 83 12 350 51 195 28 35 145 21 9 42 41 62 9 36 160 23 7 47 54 110 16 Tensile strength Tensile yield strength(a) MPa ksi MPa ksi Sheet, annealed 230 33 125 18 Sheet, hard rolled 240 35 180 Extruded bar and shapes 255 37 Extruded tubing and hollow shapes 240 Forgings... condition 49.350.8 360 375 52.254.4 4-6 As-extruded 170 190 24 .72 7.6 255 275 37. 040.0 12-15 T5 condition 215235 31.234.1 275 295 39.942.8 8-10 T6 condition 125 mm (5 in.) diam bar 340350 315335 45 .74 8.6 340360 49.352.2 5 -7 6 Elastic modulus Tension, 44.2 GPa (6.4 × 10 psi) at Solidus temperature 455 °C (850 °F) 20 °C (68 °F) Thermal conductivity 122 W/m · K (70 .5 Btu · ft · Hardness 70 to 80 HB °F) at 20... 125 18.0 1 -78 -108 260 38 125 18.0 7 93 200 235 34 1.5 150 300 160 23 9 260 500 83 12 22 F temper -78 T4 temper T6 temper(a) -78 -108 270 39 180 26.0 2 150 300 165 24 62 9.0 4 200 400 115 17 45 6.5 25 260 500 83 12 28 4.0 45 315 600 59 8.5 17 2.5 60 370 70 0 38 5.5 10 1.5 100 (a) Elevated-temperature properties were determined after prolonged heating Fig 8 Distribution of tensile properties. .. 120 250 190 27. 5 169 24.5 13 150 300 172 25.0 145 21.0 15 93 200 165 24.0 121 17. 5 25 120 250 145 21.0 1 07 15.5 26 150 300 131 19.0 93 13.5 31 200 400 114 16.5 69 10.0 34 260 500 83 12.0 45 6.5 67 315 600 41 6.0 28 4.0 140 Forgings Shear strength See Table 15 Compressive properties See Table 15 Bearing properties See Table 15 Hardness See Table 15 Directional properties See Table 17 Table 17 Typical... mechanical properties of AZ80A-F at various temperatures Testing temperature Tensile strength Yield strength Elongation in 50 mm (2 in.), % °C °F MPa ksi MPa ksi -73 -100 386 56.0 269 39.0 8.5 -18 0 355 51.5 252 36.5 10.5 21 70 338 49.0 248 36.0 11.0 93 200 3 07 44.5 221 32.0 18.0 150 300 241 35.0 176 25.5 25.5 200 400 1 97 28.5 121 17. 5 35.0 260 500 110 16.0 76 11.0 57. 0 Thermal conductivity 76 W/m ·... ksi MPa ksi F 150 22 83 12 T4 275 40 90 T61 275 40 T5 150 T7 260 Elongation in 50 mm (2 in.), % Hardness Shear strength HB HRE MPa ksi 2 53 61 125 18 13 10 52 62 140 20 150 22 1 69 80 145 21 22 110 16 2 58 70 38 125 18 1 67 78 (a) Values are the same for tensile and compressive yield strengths Table 23 Typical tensile properties of AM100A sand castings at elevated and subzero temperatures Elongation... uses Extruded products and press forgings UNS number M11800 This alloy can be heat treated Government Extruded bar, rod, and shapes: QQ-M- Mechanical Properties 31B Extruded tubing: WW- T-825 Forgings: QQ-M40B Tensile properties See Tables 7 and 8 Chemical Composition Table 7 Typical room-temperature mechanical properties of AZ80A Hardness Shear strength HB(c) HRE MPa 11 69 80 36 6 72 Tensile strength... (total), bal Mg AMS Sheet and plate: 4390 Forging: 4363 Applications ASTM Sheet and plate: B 90 Forging: B 91 Typical uses Sheet, plate, and forgings in the UNS number M13210 Government Sheet and plate: MIL-M-89 17 solution-heat-treated, cold-worked, and annealed condition (T8 temper), usable to 343 °C (650 °F) and above Forgings: QQ-M-40 Mechanical Properties Chemical Composition Tensile properties T8 temper: . 37 150 22 21 56 67 145 21 110 16 485 70 290 42 Sheet, hard rolled 290 42 220 32 15 73 83 160 23 180 26 495 72 325 47 Extruded bar, rod, and solid shapes 255 37 200 29 12 49 57 130 19 97. 10.5 21 70 338 49.0 248 36.0 11.0 93 200 3 07 44.5 221 32.0 18.0 150 300 241 35.0 176 25.5 25.5 200 400 1 97 28.5 121 17. 5 35.0 260 500 110 16.0 76 11.0 57. 0 Shear strength. See Table 7. Compressive. sheet (b) 21 70 235 34 170 25 130 19 8 200 400 125 18 115 17 105 15 30 260 500 110 16 105 15 105 15 25 315 600 97 14 83 12 83 12 15 370 70 0 76 11 55 8 55 8 50 HM21A-T5 forgings (c) 21 70 230