“…The model sample was prepared by melting metal powders consisting of stainless-steel (Fe, Cr, Ni, and Mn) and a metal deoxidizer (Al) under inert gas atmosphere. [21,24,25,36] Half of a mixture of 68 mass pct electrolytic Fe powder (purity: 95 pct, Wako Pure Chemical Industries, Ltd., Osaka, Japan), 20 mass pct Cr powder (purity: 99.9 pct, Kojundo Chemical Laboratory Co., Ltd., Saitama, Japan), 10 mass pct Ni powder (purity: 99 pct, Wako Pure Chemical Industries, Ltd., Osaka, Japan), 1 mass pct Mn powder (purity: 99.9 pct, Kojundo Chemical Laboratory Co., Ltd., Saitama, Japan) were first placed in a MgO crucible, and 1 mass pct Al powder (purity: 99.9 pct, Kojundo Chemical Laboratory Co., Ltd., Saitama, Japan) was placed on the mixture. Next, the remaining half of the mixture was placed on the Al powder.…”