采用通快TruDisk4002型同轴送粉光纤激光器，在TC4合金基材表面上制备了单道Ni基激光熔覆层，其中TC4合金的质量分数为35%、Ni60的质量分数为65%，涂层无裂纹气孔等缺陷。通过ABAQUS软件建立了涂层的有限元模型，温度场模拟结果显示，熔池出现“慧尾”现象，与实际激光热源的运行特点吻合。熔池最高温度为3200 ℃左右，激光热源前端的温度梯度大，热源后端的温度梯度小，熔池轮廓与涂层的形貌特征基本吻合，尺寸误差小于5%。从涂层残余应力场的分布来看，熔覆层两侧边缘区域和结合区附近的应力集中现象较为严重，容易萌生裂纹，熔覆层两侧的裂纹主要与高斯热源的分布特点相关，结合区的裂纹主要是由熔覆材料的热物性能差异导致的。实验结果表明，熔覆层的边缘和结合区均出现了明显的裂纹缺陷，与有限元计算结果一致。

The 35% TC4+65% Ni60 single-pass Ni-based laser cladding layer was prepared on the surface of TC4 substrate by the TruDisk4002 coaxial powder feeding fiber laser， and there were no cracks within the coating. The finite element model of the coating was established by the ABAQUS software. The simulation results of temperature field show that the molten pool has an obvious "coma tail" phenomenon， which is consistent with the motion characteristics of the actual laser heat source. The maximum temperature of the molten pool is about 3200 ℃. The temperature gradient is large at the front of the laser heat source， however that at the back end of the heat source is small. The shape characteristics of the molten pool and the coating are basically the same， and the size error is less than 5%. According to the residual stress field distribution of the coating， the stress concentration in the edge area and the bonding zone of the cladding layer is relatively large， where it is easy to form cracks. The cracks on both sides of the cladding layer are mainly related to the distribution characteristics of Gaussian heat source， and the cracks in the bonding zone are mainly caused by the difference of the thermo-physical properties of the cladding materials. The experimental results show that there occur obvious crack defects in both the edge area and the bonding zone of the coating， which is consistent with the finite element calculation results.