微粉粒度测量中形貌因素的影响

Influence of particle shape on the results of particle size measurement

从理论上分析了用电阻法(库尔特)颗粒计数器和激光粒度仪测量相同的非圆球颗粒样品时,测试结果不一致的必然性,并进行了对比实验。实验结果显示:对圆球形颗粒,两者的测试结果一致(在合理的误差范围内);但是对非圆球形颗粒,二者有明显的差异。激光粒度仪测量的结果比电阻法颗粒计数器测量的结果分布宽,所得d50的值大;同时样品的平均圆度越小,则所述的差异越大。实验结果说明:用不同原理的仪器测量磨料微粉的粒度时,必然存在测量上的差异,并且差异的大小随微粉颗粒形状的变化而变化。因此,不同原理仪器之间的测量差异不能用一个固定的数值来修正;另一方面,这种差异可以用来表征颗粒偏离圆形的程度。

Theoretical analysis and comparative tests were implemented to verify the differences between laser diffraction particle size analyzer(DPSA) and resistance sensing zone particle counter(RSPC).The results indicated that when the shape of the particle was spherical,the results were almost equal to each other in a reasonable error range.But when it was not spherical,the results were obviously different.The width of particle size distribution(PSD) and d50 from DPSA were both larger than those from RSPC.The differences between the results increased with the decrease of circularity of the particles.Results showed that when comparing the results of PSD from different instruments,there were some differences changing with particle shape.So the differences should not be modified by a fixed modification value;on the other hand,such differences could be used to character the circularity of particles.