利用 2kW的CO2 激光器在Q2 35钢表面熔覆Co基合金 +W混合粉末 ,能够获得外观质量良好的熔覆层。激光熔覆所需最小比能随W含量的增加而增大。熔覆层的组织由γ′ Co枝状晶及枝晶间γ′ Co和M7C3共晶组成 ,没有发现W颗粒。分析结果表明 ,W颗粒在Co基合金熔体中溶解 ,并在Co基合金凝固后固溶于γ′ Co。由于W溶解反应过程需要吸热 ,因而使激光熔覆所需能量增加。 A 2kW CO2 laser is used to clad Co-based alloy + W powder on the surface of Q235 steel to obtain a coating with good appearance. The minimum specific energy required for laser cladding increases with W content. The microstructure of the coating consists of γ ’Co dendrites and intergranular γ’ Co and M7C3 eutectics, and no W particles were found. The analysis results show that the W particles dissolve in the Co-based alloy melt and are solid-solution to γ ​​’Co after the Co-based alloy is solidified. As the W dissolution reaction process requires endothermic, thus increasing the energy required for laser cladding.