Abstract Severe residual stresses in metal parts made by laser powder bed fusion additive manufacturing processes (LPBFAM) can cause both distortion and cracking during the fabrication processes. Limited data is currently available for both iterating through process conditions and design, and in particular, for validating numerical models to accelerate process certification. In this work, residual stresses of a curved thin-walled structure, made of Ni-based superalloy Inconel 625™ and fabricated by LPBFAM, were resolved by neutron diffraction without measuring the stress-free lattices along both the build and the transverse directions. The stresses of the entire part during fabrication and after cooling down were predicted by a simplified layer-by-layer finite element based numerical model. The simulated and measured stresses were found in good quantitative agreement. The validated simplified simulation methodology will allow to assess residual stresses in more complex structures and to significantly reduce manufacturing cycle time.

中文翻译：

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激光粉末床融合增材制造弯曲薄壁结构中子残余应力测量与数值模拟

摘要 激光粉末床融合增材制造工艺 (LPBFAM) 制造的金属零件中的严重残余应力会在制造过程中导致变形和开裂。目前可用于迭代工艺条件和设计的数据有限，特别是用于验证数值模型以加速工艺认证。在这项工作中，由镍基高温合金 Inconel 625™ 制成并由 LPBFAM 制造的弯曲薄壁结构的残余应力通过中子衍射解决，而无需测量沿构建和横向的无应力晶格。整个零件在制造过程中和冷却后的应力通过基于简化的逐层有限元数值模型进行预测。发现模拟和测量的应力具有良好的定量一致性。经验证的简化模拟方法将允许评估更复杂结构中的残余应力并显着缩短制造周期时间。