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用激光束在４Ｃｒ１３钢基体上熔覆ＺｒＯ２与Ｎｉ合金的混合粉末，形成了分层结构的复合涂层，即表面为致密的ＺｒＯ２陶瓷层．介于陶瓷层与基体之间的是Ｎｉ基合金过渡层。组织分析表明，ＺｒＯ２层的上部为等轴晶，中下部为柱状晶，主要由ｔ＇－ＺｒＯ２相及少量沿ｔ＇晶界分布的ｍ－ＺｒＯ２相组成；Ｎｉ合金结合带呈现出树枝晶及其晶间共晶的单一凝固组织。该复合涂层的分层机制可解释为互不混溶的ＺｒＯ２与Ｎｉ合金熔珠在界面张力和浮力作用下发生离析重排，再各自重新凝固。
A laser beam was used to coat a mixed powder of ZrO2 and Ni alloy on a 4Cr13 steel substrate to form a composite coating with a layered structure, that is, the surface is a dense ZrO2 ceramic layer. Between the ceramic layer and the substrate is a Ni-based alloy transition layer. Tissue analysis shows that the upper ZrO2 layer is equiaxed and the middle and lower are columnar crystals mainly composed of t’-ZrO2 phase and a small amount of m-ZrO2 phase distributed along the t ’grain boundary. The Ni alloy band exhibits dendrite and A single solidified structure of the intergranular eutectic. The delamination mechanism of the composite coating can be interpreted as the miscible rearrangement of ZrO2 and Ni alloy beads under interfacial tension and buoyancy, and then re-solidified.