碳化钨对钴基合金激光熔覆复合涂层组织、微区成分及硬度的影响

Influence of WC on microstructure,compositions of micro-region and microhardness of laser cladding cobalt-based alloy layer

采用大功率CO2激光器制备了激光熔覆复合涂层,研究了碳化钨的添加量对钴基合金激光熔覆层凝固组织特征、微区成分、硬度梯度的影响。结果表明,碳化钨加入钴基合金后,激光熔覆层凝固组织的基本特征没有改变,但树枝晶及晶间共晶组织的凝固行为受到影响,微区内各元素的分布发生了变化;钴基合金中加入碳化钨颗粒,凝固组织的尺寸减小,晶粒细化;随着钴基合金中碳化钨加入量的增加,激光熔覆复合涂层的硬度提高。

Influence of WC on solidification structure,compositions and microhardness of laser cladding Co-based alloy layer were studied.The results show that no significant change of solidification microstructure of the laser cladding layers is observed for the addition of WC,but the WC particles affect the solidification behavior of eutectic structure between dendrites and the micro-region distribution of alloy elements in the layer.When WC is added into the Co-based alloy,the size of the solidification microstructure is decreased and the grains are refined,and its microhardness is improved with the amount of WC particle increasing.