WC-Co硬质合金特征晶面分布的研究

Orientation Distribution of Characteristic Planes in WC-Co Cemented Carbides

采用不同温度进行原位还原碳化反应制备纳米粒径的WC-Co复合粉末,进而利用放电等离子烧结技术进行快速致密化,制备得到致密的纳米晶硬质合金块体材料。系统的检测分析表明,低温下反应制备的以缺碳相为主相的复合粉经烧结致密化后块体试样存在WC晶粒高度取向分布的特征,其中,(0001)面在垂直于压力方向上面积分数达到40%,在平行于压力方向上(0001)面的面积分数仅为10.72%。与之对比,在高温反应制备的复合粉末烧结制备的块体试样中,没有出现特征晶面分布的各向异性。

Nanoscale WC-Co composite powders were synthesized by in situ reduction and carbonization reactions at different temperatures.The powders were subsequently consolidated in the spark plasma sintering（SPS）system,and then the nanocrystalline WC-Co cemented carbide bulk materials were obtained.Systematic tests and analyses show that the cemented carbides consolidated from the powders synthesized at low temperature has obvious orientation distribution of WC characteristic planes.The area fraction of the（0001）plane vertical to the sintering pressure direction occupies up to 40%,but that parallel to the sintering pressure direction is only 10.72%.In contrast,the cemented carbide bulk materials consolidated from the powders synthesized at higher temperatures do not exhibit the orientational distribution of characteristic planes.