| Austenite series high Mn Steel was studied on high strength-toughness and wear-resistance at room temperature, -78℃ and up to ultimate low temperature of -196℃, The test was made with the solution treated, cold worked (30% reduction of cross section area) and age hardened sample at 600℃, The testing results that considerable ductile fractures mixed with about 45% cleavage fractures and a little grain boundary fractures were generated up to -78℃, when the temperature came down to -196℃, grain boundary fractures with about 55% cleavage fractures were observed. Ultimate tensile strength was not demonstrated as yielding point owing to the unstable fracture. At the ultimate low temperature of -196℃, wear resistance is increased by work hardening. that is, owing to ε-Martensite, twin induced by contact working of wear surface. |
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