Co基自熔合金+WC送粉激光熔覆层再加热冷却过程中的显微组织变化特征  

Microstructure Evolution of Laser Cladding with Feeding Powder for Co-Based Alloy in Addition with WC in Reheating and Cooling Process

作　　者：刘喜明[1] 

机构地区：[1]长春工业大学,吉林长春130012

出　　处：《稀有金属材料与工程》2007年第4期621-624,共4页Rare Metal Materials and Engineering

基　　金：吉林省杰出青年基金项目(20030128);吉林省工业引导项目(20030331)

摘　　要：采用Co基自熔合金+块状WC混合粉末进行送粉激光熔覆并获得熔覆层,对熔覆层在不同温度下加热后空冷至室温,观察相应熔覆层的显微组织变化。结果表明:熔覆层850℃再加热处理,可以实现去应力退火的目的。Co基自熔合金基体的显微组织在850℃以上开始不稳定,当受到高于此温度冲击时,发生形态和显微组织结构的变化。对熔覆层中的块状WC进行再加热,当加热温度达到1000℃以上时,块状WC会发生离散,分化成细小的WC颗粒。产生这种现象的根本原因是块状WC具有先天的超细纤维、颗粒混合结构。The laser cladding with feeding powder was performed by using Co-based alloy with the massive WC mixed powder. After the cladded coating was coolled in air from different temperatures to room-temperature, the change of the microstrcture was observed. The result showed that the stress relief could be realized wihile the cladded coating was reheated at 850℃. The microstructure of Co-based alloy became instabile when cladded coating was reheated to higher than 850℃. With further rising of the temperature, the microstructure construction would change contineously. For the innate superfine fibre and pellet composite structure, the massive WC would be refined upon the reheating-up temperature being above 1000℃.

关 键 词：送粉激光熔覆 Co基自熔合金+块状WC 再加热 显微组织 

分 类 号：TG174.44[金属学及工艺—金属表面处理]