以空气作为流化气体，在微波加热喷动流化床中对高碳铬铁粉进行固相脱碳，研究不同温度和保温时间条件下对物料显微结构的变化。试验表明，加热温度800℃、保温1 h ，高碳铬铁中粗大的（Cr ，Fe）7C3开始分解，并产生少量（Cr ，Fe）23 C6‐（CrFe），呈不规则星点状分布在（Cr ， Fe）7C3晶粒内部；随着加热温度的提高和保温时间的延长，星点状的（Cr ，Fe）23 C6‐（CrFe）逐渐变大，形成类蜂窝状结构；加热温度1000℃、保温3 h ，粗大的（Cr ，Fe）7 C3晶体分解形成网络状结构。在微波加热喷动流态化条件下，高碳铬铁粉固相脱碳效果明显，反应均匀，能够有效抑制粘接失流现象。%The microstructure of high‐carbon ferrochrome powders after solid‐state decarburi‐zation in the microwave spouted fluidized bed is not only relative to rate of decarbonization ,but al‐so to the microwave field .Thus ,microwave may affect the extent of defluidization of material .In the experiment ,air was used as spouted fluidized decarbonization gas .The high‐carbon ferro‐chrome powders were heated by microwave spouted fluidized bed for solid‐state decarbonization . The change of microstructure of high‐carbon ferrochrome powders was studied in the different de‐carbonization temperature and decarbonization holding time .T he test result show s that the thick (Cr ,Fe)7 C3 in high‐carbon ferrochrome begins to decompose at 800 ℃ for 1 h .A small quantity of star‐like (Cr ,Fe)23 C6‐(CrFe) forms uniformly in the grain of (Cr ,Fe)7 C3 .With the increase of the heating temperature and holding time ,the star‐like (Cr ,Fe)23 C6‐(CrFe) grain becomes larger and changes into honeycomb structure .The thick (Cr ,Fe)7 C3 decomposes into net structure at 1000 ℃ for 3 h .With the condition of microwave heating and spouted fluidization ,the solid‐state decarburization of high‐carbon ferrochrome pow ders has some remarkable advantanges ,such as homogeneous reaction and low degree of oxidation .In addition ,defluidization is effectively re‐strained .
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