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. Austenitic chromium-nickel stainless steels remain ductile to the lowest temperature for which data are available. COMMON CRYOGENIC TEMPERATURES: Environment Temp.- Degrees F Liquid helium - 452 Liquid hydrogen - 423 Liquid nitrogen - 321 Liquid methane - 258 Solid carbon dioxide - 108 Liquid freon - 40 Water as ice 32 EFFECT OF TEMPERATURE ON YOUNGS MODULUS Room Temp. Modulus of Elasticity - ksi Alloy Tensile - psi Room Temp. At -320øF 301 106,000 25.4 x 10-6 28.6 x 10-6 302 88,000 26.2 27.2 304 87,000 24.4 26.2 347 95,000 23.3 27.6 MECHANICAL PROPERTIES AT CRYOGENIC TEMPERATURES Strength by Alloy Listed in ksi 301 302 304 304L 310 316 321 347 32øF 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 310 316 321 347 -40øF 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 310 316 321 347 -108øF 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 310 316 321 347 -258øF 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 310 316 321 347 -321øF 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 310 316 321 347 -423øF 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 - - - -