超细多元固溶体添加方式对合金金相组织特征的影响

Influence of Addition Way of Superfine Multicomponent Solid Solution on Metallographic Structure Characteristics of Alloy

本文探讨硬质合金数控刀片基体立方相弥散均匀分布的制备方法。采用超细(Ti,W)C﹑(Ta,Nb)C﹑WC﹑Co粉制备了WC-5%(Ti,W)C-5%(Ta,Nb)C-6%Co合金,采用超细近饱和的(Ti,W,Ta,Nb)C﹑WC﹑Co粉制备了WC-10%(Ti,W,Ta,Nb)C-6%Co合金。通过X衍射和扫描电镜研究不同温度下的组织结构特征,研究结果表明:制备WC-5%(Ti,W)C-5%(Ta,Nb)C-6%Co合金时,WC于1 200℃向未饱和的(Ti,W)C固溶体进行扩散,形成W含量更多的(Ti,W)C相,且(Ti,W)C和(Ta,Nb)C于1 200～1 300℃发生固溶反应,形成(W,Ti,Ta,Nb)C相,导致(Ti,W,Ta,Nb)C相粗大;而采用超细(Ti,W,Ta,Nb)C﹑WC﹑Co粉制备得到WC-10%(Ti,W,Ta,Nb)C-6%Co合金具有立方相弥散分布的特征。

The paper deals with methods of preparation of the uniform distributied cubic phase in the carbide numerical control blade matrix.The WC-5%（Ti,W）C-5%（Ta,Nb）C-6% Co alloy was prepared using WC, Co and ultrafine（Ti,W）C and（Ta,Nb）C powders. The WC-10%（Ti,W,Ta,Nb）C-6%Co alloy was prepared using WC, Co and ultrafine saturated（Ti,W,Ta,Nb）C powders. X-ray diffraction and Scanning Electron Microscopy were used to study the characteristics of microstructures at different temperatures. The results show that during the process of preparation of WC-5%（Ti,W）C-5%（Ta,Nb）C-6%Co alloy,The WC diffused to the unsaturated（Ti,W）C solid solution at 1200 ℃ to form the（Ti,W） C phase with more W content. And（Ti,W） C and（Ta,Nb）C form solid solution at 1 200～1 300 ℃,which resulted in the coarse（Ti,W,Ta,Nb）C phase. And the WC-10%（Ti,W,Ta,Nb）C-6%Co alloy had the characteristic of cubic phase dispersion when the ultrafine（Ti,W,Ta,Nb）C, WC and Co powder were used.