添加Co对碳化钨颗粒增强表层复合材料性能的影响  

Effect of Co Addition on Microstructure of Matrix in Tungsten Carbide Surface Reinforced Composite

作　　者：山泉[1] 李祖来[1] 蒋业华[1] 周荣[1] 隋育栋[1] 陈志辉[1] 

机构地区：[1]昆明理工大学材料科学与工程学院,昆明650093

出　　处：《材料研究学报》2012年第5期551-556,共6页Chinese Journal of Materials Research

基　　金：国家自然科学基金50871048资助项目~~

摘　　要：制备WC-Co表层增强复合材料,观测复合层的显微组织和基体中的生成相,研究了添加Co对碳化钨颗粒增强表层复合材料性能的影响。结果表明:Co的加入使复合层中的基体组织中产生了细小粒状珠光体和屈氏体,降低了材料的脆性倾向,提高材料整体性能。金属液浸入预制层后,沿基材至复合层表面方向,金属液的温度递减,热扩散作用小,增加复合层内部基体成分不均匀性。当基体中的W、C原子浓度升高,基体中析出η型Co_3W_3C碳化物。在复合层冷却至1200℃之前,基体能够与碳化钨颗粒发生界面反应生成Co_3W_3C碳化物,提高基体的硬度,从而提高复合材料的耐磨性。WC-Co surface reinforced composite was formed by V-EPC （vacuum-expendable pattern casting）, and the microstructure of the matrix in the composite was investigated. The results show that the Co addition caused the appearance of granular pearlite and troostite in the matrix, therefore the brittle tendency of the composite was lightened. After the molten steel infiltrating into the preform, the counter-diffusion in matrix decreased from the substrate to the surface of composite, the composition of the matrix became more uneven, and the formation of the spheroidal pearlite and troostite were facilitated. When the atomic concentration of W and C in the matrix increased, Co3W3C, ηtype carbide, was easier to be separated out. Before the temperature of the composite drop to 1200 ℃, Co3W3C could precipitate in the interface reaction between the matrix and the tungsten carbide particles, the hardness of the matrix would be increased, and then the abrasive resistance of the composite could be improved.

关 键 词：复合材料 表层复合材料 V-EPC 粒状珠光体 Co3W3C 界面反应 

分 类 号：TB33[一般工业技术—材料科学与工程]