稀土对钴基合金及硬质合金的影响

THE INFLUENCE OF RARE EARTH ON Co-BASED ALLOY AND CEMENTED CARBIDE

本文用多种检测手段对钴基合金与硬质合金进行了观察分析。结果表明：微量稀土元素使钴基合金抗拉强度提高约一倍，孔隙度有所下降，孔隙分布变得细散均匀，稀土相主要分布在合金孔隙处及晶界、相界处，也有少量存在于Co相与WC相内．形态多呈球形，尺寸一般＜0．5μ．成分为Y2WO6化合物及Y2Co金属间化合物．稀土的加入提高了Co相的层错能，层错宽度明显减少。稀土在晶界及相界的偏聚使合金的组织结构细化和均匀化了．

The observation and analysis have been made on Co-based alloy and cemented carbide with various examining methods in the paper. Tbe result shows:Trace rare-earth element can make tensile strength of Co-based alloy increase about one time,porosity reduce slightly, distribution of pores became dispersed and homogeneous. Rare-earth phase distributes mainly in the pores,grain boundary and phase boumdary of alloys,and a little in the Co-phase and WC-phase. The shape is normally balls with size below 0. 5 micron. The composition is Y2WO6 compoumd and Y2Co imter-metallic compoumd. The addition of rare-earth enhances stacking jault energy of Co phase. width of stacking fault decreases obviously. The bias precipitation of rare-eaeth in tbe grain boundary and phase boundary results in a smaller and homogenized alloy construction