The austenitic chromium-nickel stainless steels are cold formed (bent, drawn, shaped) and the cold forming imparts a higher strength than for the original starting annealed condition. It is not typical to heat these stainless steels for forming as is often done with carbon steel. The following are the designations of cold worked tempers as defined by ASTM A 666, Standard Specification for Austenitic Stainless Steel, Sheet, Strip, Plate & Flat Bar. 1/4 Hard, 1/2 Hard, 3/4 Hard, Full Hard Reheating the cold worked austenitic stainless steels at temperatures below 370C (700F) increases the tensile strength. Reheating above 425C (900F) lowers the strength and increases the ductility. Cold working increases the fatigue strength of the austenitic stainless steels. However, the fatigue strength of these cold worked alloys is reduced by notches, as compared to notched fatigue strength in the annealed condition. Fatigue Strength (Endurance Limits) of Cold Worked Stainless Steels: AISI Type Temper Endurance Limit - ksi 301 Full Hard 80 302 Full Hard 75 303 1/4 Hard 48 304 Annealed 35 304 1/2 Hard 70 304 3/4 Hard 92 347 3/4 Hard 88 Minimum Tensile Strength of Cold Rolled Sheet & Strip for 304 The other common 300 series alloys are similar. Rockwell C Temper Tensile ksi Yield ksi Elong. % Hardness 1/4 Hard 125 75 23 25 1/2 Hard 150 110 16 32 3/4 Hard 175 135 11 37 Full Hard 185 140 8 41 Extra Full Hard 200 - - 45 Tensile Strength of Cold Drawn Cr-Ni Stainless Steel Wire Diameter Range of 0.126 - 0.375" AISI TYPE TEMPER YIELD-ksi TENSILE-ksi ELONG.% 302 1/4 hard 90-125 120-140 15-25 1/2 hard 120-150 145-176 10-17 3/4 hard 150-180 170-200 5-10 * Full hard 180-220 190-230 2-5 * Typical of wires used in making stranded wire rope 304 1/4 hard 90-110 120-140 20-30 1/2 hard 120-140 130-170 10-18 3/4 hard 140-170 170-200 5-10 Full hard 170-210 200-240 2-5 309S 1/4 hard 80-90 110-130 15-25 1/2 hard 105-125 125-155 10-11 3/4 hard 125-150 140-180 8-12 Full hard 150-185 160-190 4-8 310S 1/4 hard 80-90 110-130 15-25 1/2 hard 105-125 125-155 10-11 3/4 hard 125-150 140-180 8-12 Full hard 150-185 160-195 4-8 316 1/4 hard 80-100 110-130 20-30 1/2 hard 105-125 135-155 12-20 3/4 hard 135-165 165-195 8-12 Full hard 155-185 185-215 3-6 321 1/4 hard 90-110 120-140 20-30 1/2 hard 120-140 150-170 10-18 3/4 hard 140-170 170-200 5-10 Full Hard 170-210 200-240 2-5 347 1/4 hard 85-105 115-135 15-25 1/2 hard 110-130 140-160 10-13 3/4 hard 140-170 170-200 5-10 Full hard 160-190 190-220 3-6 TENSILE PROPERTIES OF AUSTENITIC STAINLESS STEELS FOR VARIOUS AMOUNTS OF COLD WORKING STRENGTH IN ksi for % COLD REDUCTION SHOWN ALLOY 0 10% 20% 30% 40% 50% 60% 301 Tensile 120 150 168 184 198 210 222 Yield 40 87 120 148 170 185 202 Elong. 75% 58% 42% 32% 22% 15% 6% 302 Tensile 93 108 122 138 152 168 180 Yield 37 91 107 120 134 147 160 Elong. 67% 42% 30% 20% 15% 10% 6% 303 Tensile 91 106 125 148 171 196 - Yield No data Elong. 63% 47% 29% 19% 15% 12% - 304 Tensile 86 98 113 130 146 158 169 Yield 34 69 97 120 135 145 152 Elong. 53% 36% 25% 16% 13% 10% 6% 304L Tensile 83 106 122 138 154 170 - Yield 32 72 97 120 138 152 - Elong. 57% 35% 23% 15% 10% 5% - 309S Tensile 80 87 98 115 135 151 165 Yield 37 57 82 102 122 140 153 Elong. 55% 45% 30% 14% 9% 5% 3% 310S Tensile 86 108 126 140 153 166 174 Yield 45 67 97 125 140 148 152 Elong. 45% 29% 15% 8% 6% 5% 5% 316 Tensile 85 95 110 130 142 150 169 Yield 38 70 98 118 128 137 148 Elong. 60% 40% 21% 12% 8% 6% 5% 321 Tensile 88 100 115 135 150 160 168 Yield 32 70 100 120 134 142 145 Elong. 55% 45% 26% 13% 8% 5% 4% 347 Tensile 96 105 122 144 159 168 173 Yield 40 78 109 128 138 143 149 Elong. 50% 33% 12% 8% 7% 6% 5%