自蔓延高温还原法制备钨粉的研究

Preparation of Tungsten Powder by SHS with Reduction Process

采用 SHS还原法以 Ca WO4 ,Mg粉为原料制备钨粉。研究了 Ca WO4 - Mg合成过程中的物理化学变化 ,压坯压力、稀释剂和浸出对燃烧过程和产物的影响。随着压坯压力的增加 ,燃烧产物的空隙率和钨粉颗粒的粒度呈递减趋势。添加稀释剂 (钨粉 ) ,钨粉颗粒的粒度有所增大。通过进一步碱浸可提高钨粉的纯度。最终产物的成分光谱分析和粒度分析结果表明 :可得到平均粒径为 0 .87μm,比表面积 1.0 9m2 /g,纯度≥ 99.0 %的钨粉。

Self-propagating high-temperature synthesis(SHS) with reduction process was used to fabricate tungsten powder from the system CaWO4-Mg. The physico-chemical change during heating and the effects of pressure of sample and diluent on product have been studied. The experimental results show that with increasing pressure of sample, the porosity of combustion product and the particle size of final tungsten powder decrease. Additive diluent could increase the particle size of final tungsten powder. The purity of tungsten is improved by leaching in NaOH solution. The results of spectral analysis and particle size distribution of final tungsten powder show that the final W powder has median diameter of 0.87 mum, Specific surface area of 1.09 m(2)/g and purity of above 99.0%.