等离子体气相蒸发法制备超细球形钨粉

Preparation technology of spherical ultrafine tungsten powders with plasma evaporation method

采用等离子体蒸发法实现了钨粉的球化、细化和纯化,制备出超细球形钨粉,同时研究了载气量和送粉量等工艺参数对球化后钨粉形貌和粒度的影响.结果表明,等离子体处理后产品仍为纯金属钨粉,形状由不规则变为球形,颗粒平均粒径由原料的3～5μm减小至200nm左右,振实密度由13.21g/cm3提高到15.78g/cm3.等离子体气相蒸发法是制备高振实密度高纯微细球形粉体的有效技术.

With plasma evaporation method, spheroidization, refinement and purification, spherical ultrafine tungsten powders were prepared, and the effects of the carrier gas flowing rate and tungsten powder feeding rate on the shape and size of products were studied. The results showed that spherical pure tungsten powders can be obtained from irregular pow- der,and the tap density was much enhanced after plasma processing. The average size was reduced from 3-5 μm to 200 nm and the tap density was raised from 13.21 g/cm^3 to 15.78 g/cm^3. So plasma was a promising method for preparation of spherical ultrafine powders with high tap density and high purity.