Abstract The cladding layer formed by laser cladding is formed by solidification of the molten pool. The quality of the cladding layer is directly determined by the evolution of the molten pool. The numerical simulation of the evolution of the molten pool is carried out, revealing the relationship between different powers and the evolution of the molten pool. The results show that the volume of the molten pool exhibits a nonlinear expansion of “expansion-shrinkage-re-expansion” before reaching the steady state, and the volume and expansion rate of the molten pool are determined by the laser power. In addition, the degree of shrinkage of the molten pool and the speed of convection can also be controlled by the laser power. When the laser power reaches a certain level, evaporation occurs on the surface of the molten pool. The convection pattern of the molten pool can be changed by evaporation. However, due to the impact of shielding gas and Marangoni movement, the effect of evaporation on the geometry of the cladding layer is limited.

中文翻译：

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激光功率对熔池演化和对流的影响

摘要 激光熔覆形成的熔覆层是由熔池凝固形成的。熔池的演化直接决定熔覆层的质量。对熔池演化进行数值模拟，揭示了不同功率与熔池演化的关系。结果表明，熔池体积在达到稳态前呈现出“膨胀-收缩-再膨胀”的非线性膨胀，熔池体积和膨胀速率由激光功率决定。此外，熔池的收缩程度和对流速度也可以通过激光功率来控制。当激光功率达到一定水平时，熔池表面就会发生蒸发。熔池的对流模式可以通过蒸发来改变。然而，由于保护气体和 Marangoni 运动的影响，蒸发对熔覆层几何形状的影响是有限的。