摘要
The vertical sections of the La−Fe−B system were investigated using electron probe microanalysis and differential thermal analysis.Based on the microstructures and phase compositions of the as-cast and equilibrium alloys,together with their heat flow−temperature curves,phase diagrams for three vertical sections were drawn:La_(x)Fe_(82)B_(y)(x+y=18),La_(x)Fe_(70)B_(y)(x+y=30)and La_(x)Fe_(53)B_(y)(x+y=47),where x and y represent mass fraction of La and B,respectively,%.Additionally,according to the phase diagrams,the compound La2Fe14B was identified as a stable phase at high temperatures.It was found to be stable between 926.2 and 792.6℃;at low temperatures,however,it decomposed into α-La,α-Fe and LaFe_(4)B_(4),according to the reaction La_(2)Fe_(14)B→α-Fe+α-La+LaFe_(4)B_(4).
采用电子探针显微分析和差热分析研究La−Fe−B体系的垂直截面。根据铸态合金和平衡合金的显微组织和相组成及其热流−温度曲线,绘制3个垂直截面相图:La_(x)Fe_(82)B_(y)(x+y=18)、La_(x)Fe_(70)B_(y)(x+y=30)和La_(x)Fe_(53)B_(y)(x+y=47)(x和y分别为La和B的质量分数,%)。此外,根据相图,化合物La_(2)Fe_(14)B被确定为高温稳定相。该化合物在926.2~792.6℃范围内稳定存在,低温下分解为α-La、α-Fe和LaFe_(4)B_(4),其反应方式为La_(2)Fe_(14)B→α-Fe+α-La+LaFe_(4)B_(4)。
基金
financially supported by the Natural Science Foundation of China(No.51761007)
the Guangxi Natural Science Foundation,China(Nos.2019GXNSFAA245003,2018GXNSFAA294069,2020GXNSFFA297004,2021GXNSFDA075009)
the Guangxi Project of Science and Technology,China(Nos.AD19110078,AA18242023-1)
the Scientific Research Foundation of Guilin University of Electronic Technology,China(No.UF18016)
the Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials(No.2019GXYSOF08),China
the Guangxi Key Laboratory of Information Materials,China(No.191012-Z)
the National Key R&D Program of China(No.2016YFB0700901)
financial support from the foundation for Guangxi Bagui scholars,China。
