钨钴复合粉在流态化床中的碳化反应过程研究

将钨钴复合氧化物置于自主研发的高温流态化床中,采用氢气作为还原剂,经过还原反应后得到类金属化合物-钨钴复合粉(Co7W6和W),再加入炭黑进行碳化反应,得到最终产品碳化钨钴复合粉。试验过程进行实时在线取样,对样品进行相组成和Co、C、O、N等元素含量分析。研究结果发现,碳化过程非常迅速,其中类金属化合物Co7W6按照Co7W6→Co6W6C→Co3W3C→WC进行碳化,单质金属W是按照W→W2C→WC进行碳化,并且W2C比Co3W3C更易碳化。同进还发现,不需要经过CoW3C相可以实现完全碳化。

Study on Carbonization Process of W-Co Composite Powder in Fluidized-bed

Tungsten cobalt composite oxide was placed on the self-developed high temperature fiuidized-bed to prepare W-Co composite powder （C07W6 and W） by reduction reaction using hydrogen as reducing agent. Then, carbon black was added to obtain the final product of WC-Co composite powder by carbonization process. The phase composition and element content were studied on the samples obtained at different stages while the temperatures inside the fluidized- bed were recorded synchronously. The results show that, the carbonization process is very fast according to the tempera- ture variation curves. The Co7W6 metal compound is carbonized as the sequence of Co7W6→Co6W6C→Co3W3C→WC, and the elemental W is carbonized as W→W2C→WC. W2C is carbonized more easily than Co3W3C. It is also found that CoW3C is not indispensable for complete carbonization.