高纯镁砂与西藏铬矿间固相反应的研究

Solid-phase reaction between high purity magnesia and chrome ore from Tibet

为了考察镁砂与铬矿间的反应过程及其特征,以高纯镁砂颗粒和西藏铬矿细粉为原料,在200 MPa下制成50 mm×20 mm的试样,然后在高温隧道窑中于1 750℃烧成,并对烧成后的试样进行BSE和EDS分析。结果表明:随着距离镁砂-铬矿边界距离的增加,镁砂颗粒内部Cr、Fe、Al的质量分数均减少,镁砂颗粒边缘富含Fe,颗粒内部Cr含量较高。镁砂-铬矿边界呈直接结合,镁砂内的尖晶石相分布较均匀。

For investigating the process and character of reaction between magnesia and chrome ore,the specimens with the size of Ф50 mm x20 mm were prepared with high purity magnesia particles and chrome ore pow- der from Tibet as starting materials under 200 MPa,firing at 1750 ℃ in a high-temperature tunnel kiln. The fired specimens were-analyzed by SEM and EDS. The results showed that the mass fraction of Cr, Fe and AI in magnesia particles decreased with the increase of distance from the magnesia-chromite boundary, the border of magnesia particles displayed Fe-rich,the inside of particles exhibited high Cr content. The direct bond formed at the magnesia -chromite boundary and the spinel phase in magnesia distributed uni- formly as well.