石墨微粉的流动性及其影响因素

针对石墨微粉在运输过程中易振实,严重影响施放烟幕质量的问题,根据Carr指数法原理测试多个样品的流动性能,并通过模拟汽车运输振动试验获得石墨微粉的具体振实情况,研究粉体压缩度、粒径分布、流散剂包覆效果等因素对流动性能的影响规律。结果表明:当粒径在4.0~13.0μm的石墨微粒的体积分数大于60%、中值粒径为5.5μm左右,且流散剂混合与包覆效果较均匀时,石墨微粉的流动性和抗振实性能较好。

Research on Flowability of Graphite Powders and Its Influencing Factors

In order to solve the problem of graphite powders becoming highly dense in transit,which could greatly reduce the quality of discharging smoke,the flowability of several samples was tested on the basis of Carr index theory.The details of compaction were gained by a vibration-simulated test.Then the impact of several factors,such as compression degree,size distribution,surface coating quality on flowability was studied.The results showed that the graphite powder has better flowability and compaction-resistant performance under the following conditions.The volume fraction of graphite particles between 4.0 μm and 13.0 μm was larger than 60%.The median diameter d50 was about 5.5 μm.The graphite powder was well mixed and coated by the free-flowing agents.