The Warren-Kobayashi-Lobkovsky-Carter (WKLC) coupled phase and orientation field model, originally developed for polycrystalline materials solidification, is extended for the simulation of grain evolution in metal additive manufacturing. Firstly, a moving heat source is incorporated to the model for generating a transient melt pool. Additionally, the relaxation time of the orientation field evolution is drastically increased below melting point through a temperature-dependent exponential term, which prevents grain coarsening after solidification. These adjustments allow qualitative simulation of columnar grains across various melting conditions.

中文翻译：

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扩展多晶凝固相场模型以模拟金属增材制造中的晶粒演化

Warren-Kobayashi-Lobkovsky-Carter (WKLC) 耦合相和取向场模型最初是为多晶材料凝固而开发的，现已扩展用于模拟金属增材制造中的晶粒演化。首先，将移动热源纳入模型中以生成瞬态熔池。此外，取向场演化的弛豫时间通过与温度相关的指数项在熔点以下急剧增加，从而防止凝固后晶粒粗化。这些调整允许对各种熔化条件下的柱状晶进行定性模拟。