Fundamental understanding of the high-temperature interaction between stainless steel (SUS) and B₄C is indispensable for estimating and characterizing the fuel debris generated during severe accidents of boiling water reactors (BWR), such as Fukushima Dai-ichi Nuclear Power Station (FDNPS, also referred to as “1F”) in Japan. This study aims at systematically characterizing the solidified products of molten SUS-B₄C mixtures by powder X-ray diffraction (PXRD), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), and thermogravimetry-differential thermal analysis (TG-DTA) with a range of the B₄C content relevant to the fuel debris composition expected at 1F, in order to elucidate the solidification and re-melting mechanisms. The results indicated that γ-Fe and (Cr,Fe)₂B are the major solidified phases when the B₄C content is below 3 mass%, while (Cr,Fe)₂₃(C,B)₆ is formed as an additional third phase when the B₄C content exceeds 3 mass%. The solidification of molten SUS-B₄C mixture and re-melting of solidified SUS-B₄C melt are eutectic, which is mainly controlled by the pseudo-binary Fe–B system that is influenced by the C and Cr content and additional minor components such as Mo.

对不锈钢（SUS）和B ₄ C之间的高温相互作用的基本了解对于估算和表征在福岛第一核电站（FDNPS）等沸水堆（BWR）严重事故期间产生的燃料碎片至关重要。 ，在日本也称为“ 1F”）。这项研究旨在通过粉末X射线衍射（PXRD），扫描电子显微镜-能量色散X射线光谱（SEM-EDS）和热重分析-差示热分析系统地表征熔融SUS-B ₄ C混合物的固化产物（ TG-DTA），其范围为B ₄为了阐明凝固和重熔机理，与预期在1F的燃料碎片成分有关的C含量。结果表明，γ-Fe和（铬，铁）₂ B是主要固化的相当乙₄ C的含量低于3质量％，而（铬，铁）₂₃（C，B）₆作为一个额外的形成当B ₄ C的含量超过3质量％时为第三相。熔融的SUS-B ₄ C混合物的凝固和凝固的SUS-B ₄ C熔体的重熔是共晶的，这主要受拟二元Fe-B系统的控制，该系统受C和Cr含量以及其他微量元素的影响钼等成分