Thermal distortion and residual stresses are two important factors that affect the quality and reliability of steel parts manufactured by laser powder bed fusion (LPBF) processes. A cost-effective model for evaluation of those heat effects is needed to refine the manufacturing process and provides insights into the product design and heat treatment. In this study, the layer heating method and sophisticated track-layer scanning method were applied to simulate the thermo-mechanical response of IN625 tube parts built by LPBF. Based on the similarity of temperature field in each layer deposit, a swept mesh was constructed to perform the thermal analysis for top layer, with the rest of layers referring to the temperature by node number offsetting. A novel explicit finite element analysis code accelerated by graphics processing unit was used for the massive-element numerical analysis. The computational accuracy and efficiency of the layer heating and track-layer scanning methods were compared in detail. It is shown that layer heating method can efficiently capture the pattern of stress distribution with reasonable accuracy in stress magnitude. The grouped track-layer scanning method can predict the residual stress and strain more accurately at a higher cost (5 ~ 10×). The elastic strain distribution was compared with the measurement by X-ray diffraction, confirming the accuracy of residual stress prediction.

热变形和残余应力是影响激光粉末床熔融 (LPBF) 工艺制造的钢件质量和可靠性的两个重要因素。需要一种具有成本效益的模型来评估这些热效应，以改进制造过程并提供对产品设计和热处理的见解。在这项研究中，应用层加热方法和复杂的轨道层扫描方法来模拟由 LPBF 制造的 IN625 管零件的热机械响应。根据各层沉积温度场的相似性，构建扫描网格对顶层进行热分析，其余各层以节点编号偏移的温度为参考。一种新的图形处理单元加速的显式有限元分析程序被用于质量单元数值分析。详细比较了层加热和轨道层扫描方法的计算精度和效率。结果表明，层加热方法可以有效地捕获应力分布模式，并且应力大小具有合理的精度。分组跟踪层扫描方法可以以更高的成本（5~10×）更准确地预测残余应力和应变。将弹性应变分布与 X 射线衍射测量值进行比较，证实了残余应力预测的准确性。结果表明，层加热方法可以有效地捕获应力分布模式，并且应力大小具有合理的精度。分组跟踪层扫描方法可以以更高的成本（5~10×）更准确地预测残余应力和应变。将弹性应变分布与 X 射线衍射测量值进行比较，证实了残余应力预测的准确性。结果表明，层加热方法可以有效地捕获应力分布模式，并且应力大小具有合理的精度。分组跟踪层扫描方法可以以更高的成本（5~10×）更准确地预测残余应力和应变。将弹性应变分布与 X 射线衍射测量值进行比较，证实了残余应力预测的准确性。