Abstract Experimental and numerical study regarding fracture in laser-processed steel components is addressed in the present work. Samples of stainless steel (SS) 316L were obtained by an additive manufacturing process, the directed energy deposition (DED), using different deposition orientations, and tested experimentally until fracture. Microstructural investigations, prior and after fracture, were performed by observing micro-cavities and porosities and fractographic images of the fracture surfaces. A numerical approach based on the phase-field diffusive model was utilised in a micromechanical pressure-dependent plasticity context using Rousselier damage criterion and implemented within the finite element framework. The ability to predict the material failure induced by the porosity evolution through the micro-void growth mechanism is considered as a key feature of the proposed material model. The performance of the numerical model is assessed via material deformation analysis, including initiation and propagation of cracks, which are found to be in good agreement with the experimental and fractographic observations from the fabricated tensile test samples.

中文翻译：

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使用相场方法制造 316L 不锈钢的定向能量沉积 (DED) 中的断裂分析

摘要 目前的工作涉及激光加工钢部件断裂的实验和数值研究。不锈钢 (SS) 316L 样品通过增材制造工艺、定向能量沉积 (DED) 获得，使用不同的沉积方向，并进行实验测试直至断裂。通过观察微孔洞和孔隙度以及断裂表面的断口图像，对断裂前后的微观结构进行研究。基于相场扩散模型的数值方法在微机械压力相关塑性环境中使用 Rousselier 损伤准则，并在有限元框架内实施。通过微孔洞生长机制预测由孔隙度演变引起的材料失效的能力被认为是所提出的材料模型的一个关键特征。数值模型的性能通过材料变形分析进行评估，包括裂纹的萌生和扩展，发现其与制造的拉伸试验样品的实验和断口观察非常一致。