| 摘要 |
Provided are austenitic steel having superior machinability and cryogenic temperature toughness in weld heat affected zones thereof and a method for manufacturing the same, the austenitic steel comprising, in weight %, 15 to 35% of manganese (Mn), carbon(C) that satisfies 23.6C+Mn ‰¥ 28 and 33.5C-Mn ‰¤ 23, 5% or lower (but not 0%) of copper (Cu), chrome (Cr) that satisfies 28.5C+4.4Cr ‰¤ 57 (but not 0%), the remainder being Fe and other inevitable impurities, the Charpy impact value of the weld heat affected zones at -196°C being 41J or higher. According to the present invention, austenitic steel having superior machinability and cryogenic temperature toughness in weld heat affected zones thereof is provided in which the cryogenic steel is obtained in an inexpensive manner, a stable austenite phase can be formed at a low temperature and the generation of carbide can be effectively inhibited. |
