无铁污染法制备高纯超细结晶型硅微粉的研究

Study on preparation of silicon micro-powders with high-purity and ultra-thin crystals by iron free contamination method

以高硬度钇稳定氧化锆球为研磨介质,对衬聚氨酯搅拌磨无铁污染法制备高纯超细结晶硅微粉进行了研究。研究了结晶硅微粉粒径特征参数D50随搅拌粉磨时间延长的变化规律,考察了钇稳定氧化锆球对结晶硅微粉的污染程度,探讨了1μm以下结晶硅微粉的形貌特征。实验结果证明:用该搅拌磨磨细石英砂并经过沉降分级,可获得SiO2质量分数为99.91%,粒径为1μm以下的高纯超细结晶硅微粉,不经分级可以获得粒径为61.5μm以下占99.99%的结晶硅微粉,但难以获得球形结晶硅微粉;钇稳定氧化锆珠对结晶硅微粉的污染程度小,磨损带进的ZrO2杂质仅占0.0246%,带进的Y2O3杂质为0.0014%。

Study was conducted on preparation of silicon micropowders with high-purity and ultra-thin crystals by iron free contamination method and agitator lined with the polyurethane for grinding, using oxidizing zirconium balls that contain yttrium as grinding medium. The changing law of the special parameters D50 of quartz micropowders with the variations of grinding time of the agitator mill, contamination level of oxidizing zirconium balls on the quartz micr powders, and the chemical composition and microcosmic shape of the quartz micro-powders which is under 1μm are discussed. The test result showed that after free-settling and classification of the quartz micro-powders a mass fraction of 61.5 μm SiO2 could be obtained and for the size fraction of silicon micro-powders with high-purity and ultra-thin crystals under 1/tin, silicon crystal mlcro-power of size 61.5μm and under, taking up 99.91% without classification could be obtained. But it is very difficult to achieve the spherical quartz micropowders by grinding pollution level of crystal silicon micro powder micro powders made by yttrium stabilizing zirconia bead was small , and ZrO2 impurity caused by abrasion took up only 0. 0246 % and Y2O3 impurity brought in was about 0.0014 %.