High-throughput experiments on Cr-rich particle formation in Fe-Cr-Al alloys using combinatorial samples with continuous concentration gradients

Abe, Yosuke  ; Mohamad, A. B. ; Sasaki, Taisuke*; Yamashita, Shinichiro   ; Okubo, Nariaki   ; Ukai, Shigeharu  

Embrittlement due to the formation of Cr-rich embrittlement phases ( particles) is a concern in Fe-Cr-Al (ODS) alloys being developed as accident tolerant fuel cladding for light water reactors, but the compositional range of Cr and Al in which embrittlement occurs has not been determined. In this study, combinatorial samples with continuous concentration gradients were prepared by interdiffusion heat treatment of Fe-Cr-Al alloys, and high-throughput composition and hardness measurements were performed before and after thermal aging. The compositional range obtained was sufficient to determine the precipitation boundaries of the particles. Solid solution strengthening was studied from the hardness data after diffusion heat treatment, suggesting that slow cooling leads to spinodal decomposition and formation of Al precipitates. The precipitation boundary of particles was refined from the hardness data after thermal aging.