碳化硅粉的球磨整形研究

Research of Reshaping Silicon Carbide Powder

采用机械球磨法对不规则形状碳化硅粉体进行了整形研究。分析了三种不同粒径碳化硅粉体在不同球磨时间下,碳化硅粉体的形貌、圆度、粒径大小及分布的变化,并进一步对比分析了整形前后碳化硅粉烧成坯体的表观形貌变化,确定了碳化硅粉的最佳球磨时间。结果表明:随着机械球磨时间的延长,碳化硅粉体的粒径先减小后缓慢增大,即碳化硅粉体团聚程度加重,出现了球磨极限;碳化硅粉体的圆度值有所减小,即整形后碳化硅颗粒球形度更高;碳化硅粉体的粒径分布变窄,粒径更为均一;且整形后烧成坯体的颗粒外形更为圆滑;因此,碳化硅粉机械整形的最佳球磨时间为40 h。

The irregular shape of SiC powders were reshaped by the method of mechanical ball milling. Three different size of SiC powders were analyzed under different ball milling time. The mor-phology ,roundness, particle size and its distribution of the SiC powders before and after reshaping were characterized. The re-sults show that particle size of the SiC powders firstly decreased and then increased slowly with the increase of mechanical ball milling time,namely SiC powders were agglomerated,ball milling reached the limit. Roundness of the SiC powders decreased, namely the sphericity of SiC powders became higher. The particle size distribution of SiC powders reduced in width, the particle size of SiC powders were more uniform. Therefore, the optimal mechanical ball milling time of SiC powders was 40h.Key words