摘要
采用XRD和TEM技术对Ni2 1+ 2 0 %WC + 0 5 %CeO2 合金粉激光熔覆层经过后续热处理的组织与性能进行了研究。结果表明 ,与未经处理的熔覆层相比 ,经 5 0 0℃处理后熔覆层的组织和硬度都基本不变 ;经75 0℃或 80 0℃处理后 ,尽管熔覆层相组成相同 ,但一些相的含量发生了变化 ,而且在熔覆层基体上析出了更多的Ni3B、Ni4 B3等化合物 ,亚稳的M7C3相也向M2 3C6 稳定相转化 ,同时析出的化合物质点有一定程度的粗化 。
The microstructure and hardness of Ni21+20%WC+0 5%CeO 2 alloy powder laser clad layer after post heat treatment were investigated by XRD and TEM.The experimental results show that compared with the layers without heat treating,the microstructure and hardness of the layers with heat treated at 500℃ remain unvaried;although the phase composition at the layers heat treated at 750℃ or 800℃ is the same,the content of some phases is changed,More Ni 3B and Ni 4B 3 phases are precipitated on the substrate of the clad layer,and M 7C 3 transforms into steady M 23 C 6.Meanwhile the precipited phases coarsening,resulting in obviously decreasing of hardness.
出处
《金属热处理》
CAS
CSCD
北大核心
2003年第9期28-31,共4页
Heat Treatment of Metals
关键词
激光熔覆层
硬度
显微组织
laser clad layer
hardness
microstructure