Zr-Fe-Si体系580 ℃富锆端相关系研究

Study on the phase relations in Zr-rich region of Zr-Fe-Si system at 580 ℃

摘要:

采用平衡合金法，通过X射线粉末衍射（XRD），扫描电子显微镜（SEM）及能谱分析（EDX）等手段研究了Zr-Fe-Si体系富Zr端580 ℃下的相平衡关系，包括5个两相区和2个三相区，两相区为Zr2Si+Zr2Fe、Zr2Fe+ZrFe2、Zr2Fe +Zr3Fe、Zr2Si+Zr5Si3和α-Zr+Zr2Si，三相区为α-Zr+Zr2Fe+Zr3Fe和α-Zr+Zr2Si+Zr5Si3。观察到已有Zr-Fe和Zr-Si相图中在580 ℃下为不稳定相的Zr2Fe和Zr5Si3，没有观察到在Zr-Si相图中标记为稳定相的Zr3Si。相同晶体结构的Zr2Si和Zr2Fe部分固溶，Fe在Zr2Si中的固溶度达到5.95 at.%，Si在Zr2Fe中的固溶度达到6.38 at.%，立方结构ZrFe2能固溶3.11 at.% Si。

Abstract:

Phase equilibria in the Zr-rich region of Zr-Fe-Si system at 580 ℃ was determined through equilibrated alloy method by using X-ray powder diffraction (XRD), scanning electron microscope (SEM) and energy dispersive x-ray analysis (EDX). Five two-phase equilibria Zr2Si + Zr2Fe, Zr2Fe + ZrFe2, Zr2Fe + Zr3Fe, Zr2Si + Zr5Si3, α-Zr + Zr2Si and two three-phase equilibria α-Zr + Zr2Fe + Zr3Fe, α-Zr + Zr2Si + Zr5Si3 were included in this study. The compounds Zr2Fe and Zr5Si3 which were marked as unstable phases at 580 ℃ in the available Zr-Fe and Zr-Si phase diagrams were observed, While the compound Zr3Si which was marked as stable phase in the Zr-Si phase diagram was not observed in this work.. It was shown that Zr2Fe and Zr2Si with same crystal structure were partially miscible. Solubility of Fe in Zr2Si is up to 5.95 at.% and solubility of Si in Zr2Fe is up to 6.38 at.%. ZrFe2 (cubic crystal structure) dissolves 3.11 at.% of Si.