AUSTENITIC-FERRITIC STAINLESS STEEL WITH EXCELLENT RESISTANCE TO DETERIORATION DUE TO THERMAL AGING

摘要

PPROBLEM TO BE SOLVED: To provide new austenitic-ferritic stainless steel which is free from deterioration in properties with time, such as increase in hardness and reduction in toughness and ductility with the lapse of time, even if used under extremely severe conditions under a high-temperature and high-pressure water environment such as a nuclear power plant. PSOLUTION: The austenitic-ferritic stainless steel contains a mixed structure of austenite phase and ferrite phase, and ferrite content in the mixed structure is 5 to 15 wt.%. When this steel is used under the high-temperature and high-pressure water environment, spinodal decomposition and precipitation of G phase consisting of Ni atoms, Si atoms and Mo atoms is suppressed. PCOPYRIGHT: (C)2008,JPO&INPIT