Enhanced disperse Ta(C, N) precipitation in reduced activation ferritic/martensitic steels by optimized two-step austenitizing

• DOI: 10.1016/j.jmrt.2024.03.041
• Publication Date: 2024-03-11T09:46:30Z
• Authors: Xiaojie Huo; Yunhe Yu; Dongyue Chen; Zhengcao Li; Chi Zhang
• Keywords: Tempering

High-density MX precipitates block the movement of dislocations during creep at high temperature and increase sink strength to point defects under irradiation. Therefore, precipitation control phase is crucial for advancement reduced activation ferritic/martensitic (RAFM) steels. In this paper, an optimized two-step austenitizing strategy was proposed enhance Ta(C, N) in RAFM steels, effects first second on enhancement were studied. During austenitizing, particles with a small radius (∼12 nm) number density (∼8.5 × 1019 m−3) precipitated by heterogeneous nucleation M23C6 boundaries retained comparatively low (900 °C). Then enhanced kept good size thermal stability below 1050 °C. Compared steels treated conventional normalizing tempering, performance significantly improved pinning effect dispersed particles. Furthermore, validated other two showing broad application prospects heat-resistant