Ag_2WO_4-Ag_2CO_3共沉淀的氢还原过程

HYDROGEN-REDUCTION OF CO-PRECIPITATED Ag_2WO_4/Ag_2CO_3 MIXTURES

化学共沉淀-氢还原法可用来制取满足合金成分要求的Ag-W复合份。本文研究了含Ag的Ag_2WO_4的氢还原过程,证明了第二阶段还原的温度和时间是影响复合粉平均粒度和还原程度的主要工艺因素。讨论了共沉淀中钨酸银在氢还原过程中的相变途径及其与还原工艺条件的关系。

The co-precipitation/reduction method enables production of the compositepowders to meet the composition requirements for certain alloys. The hydrogenreduction of silver tungstate containing extra silver content has been investigatedin the present paper. The results show that temperature and isothermal holdingtime in the second stage of reduction have the most significant effects on themean particle size and reduction extent of the composite powder obtatined. Thephase transformations or reduction paths of silver tungstate in the co-precipita-ted composites and their dependence upon the reduction process have also beendiscussed.