机电工程技术2026，Vol.55Issue(16)：30-36,7.DOI:10.3969/j.issn.1009-9492.2026.16.004
Mo元素对临氢工况奥氏体不锈钢敏化行为的影响
Effect of Molybdenum on the Sensitization Behavior of Austenitic Stainless Steel in Hydrogen-bearing Environments
摘要
Abstract
Catalytic cracking units and hydrogen energy equipment frequently operate at intermediate temperatures,where austenitic stainless steels are prone to sensitization.To clarify how molybdenum governs this behavior and to support material selection and remaining-life evaluation of pressure-bearing parts,two grades are examined:Mo-free S30408 and S31608 grade containing approximately 2%Mo(weight).Both steels are held at 650℃for a series of soaking times to induce sensitization.Their microstructural changes,degree of sensitization(DOS),and loss of mechanical performance are assessed using optical metallography,double-loop electrochemical potentiodynamic reactivation(DL-EPR)measurements,and tensile and impact testing.As the holding time increases,M23C6 carbides precipitate along the grain boundaries of both steels and gradually become more continuous,which widens the chromium-depleted regions and increases the tendency toward intergranular corrosion.The Mo-bearing S31608,however,shows slower carbide precipitation,and its DOS increases far less steeply than that of S30408.This behavior indicates that Mo improves the chemical stability near the grain boundaries,partly offsetting the sensitization-driven degradation and improving service reliability under high-temperature,hydrogen-bearing conditions.This study offers experimental support for the long-term safe operation of petrochemical and hydrogen energy facilities,refined material selection,and service life prediction,while also bearing practical value in limiting medium leakage and energy losses arising from material failure.关键词
300系列不锈钢/敏化/晶间腐蚀/冲击韧性/Mo元素Key words
300-series stainless steel/sensitization/intergranular corrosion/impact toughness/Molybdenum分类
矿业与冶金引用本文复制引用
陈星宇,周杨飞,张浩文,封小亮,贺肖,张曙东..Mo元素对临氢工况奥氏体不锈钢敏化行为的影响[J].机电工程技术,2026,55(16):30-36,7.基金项目
国家市场监管总局科技项目(2025MK172) （2025MK172）
