The austenitic stainless steels remain tough and ductile to very low temperatures. Metals such as iron and constructional steels undergo a marked decrease in ductility at lower temperatures. COMMON CRYOGENIC TEMPERATURES: Environment Degrees C Degrees F Boiling Helium - 268.6 - 454 Boiling Hydrogen - 252.5 - 418 Freezing Nitrogen - 209.9 - 346 Boiling Nitrogen - 195.8 - 319 Boiling Methane - 164.0 - 265 Solid Carbon Dioxide - 78.5 - 108 Boiling Freon 12 - 29.8 - 22 Water as ice 0.0 32 EFFECT OF TEMPERATURE ON MODULUS OF ELASTICITY Room Temp. Modulus of Elasticity - ksi Alloy Tensile - ksi Room Temp. At -196øC 301 106 25.4 x 10-6 28.6 x 10-6 302 88 26.2 27.2 304 87 24.4 26.2 347 95 23.3 27.6 MECHANICAL PROPERTIES AT CRYOGENIC TEMPERATURES Strength by Alloy Listed in ksi 301 302 304 304L 310S 316 321 347 0øC Yield 42 42 38 28 35 40 40 40 Tensile 160 120 115 98 88 90 100 100 Elong. 60% 50% 60% 58% 50% 68% 58% 60% Charpy key hole notch 39 34 37 - 38 35 32 29 in ft. lb. 301 302 304 304L 310S 316 321 347 -40øC Yield 44 43 40 30 40 45 45 45 Tensile 180 135 135 115 94 105 120 115 Elong. 40% 58% 55% 55% 70% 67% 55% 58% Charpy key hole notch No data 301 302 304 304L 310S 316 321 347 -78øC Yield 50 58 45 35 48 57 50 50 Tensile 162 164 165 138 110 120 138 136 Elong. 52% 52% 48% 50% 78% 65% 53% 52% Charpy key hole notch 21 27 26 - 30 26 25 23 in ft. lb. 301 302 304 304L 310S 316 321 347 -168øC Yield 62 62 55 40 62 73 58 50 Tensile 210 210 208 175 140 160 185 180 Elong. 44% 43% 42% 44% 90% 61% 47% 45% Charpy key hole notch 5.5 9.5 21 16 24 19 22 19 in ft. lb. 301 302 304 304L 310S 316 321 347 -196øC Yield 55 62 57 45 75 80 60 52 Tensile 275 225 225 192 151 180 211 195 Elong. 30% 40% 38% 42% 93% 19% 22% 19% Charpy key hole notch No data in ft. lb. 301 302 304 304L 310S 316 321 347 -253øC Yield - 62 69 50 96 93 68 65 Tensile - 258 250 220 180 230 248 230 Elong. - 38% 27% 41% 71% 55% 34% - Charpy key hole notch ft. lb. - - - 19 - - - -