Multiaxial plasticity and fracture behavior of stainless steel 316L by laser powder bed fusion: Experiments and computational modeling
Multiaxial plasticity and fracture behavior of stainless steel 316L by laser powder bed fusion: Experiments and computational modeling
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DOI：
10.1016/j.actamat.2020.08.066
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发表时间：
2020-10-15
期刊：
影响因子：
9.4
通讯作者：
Beese, Allison M.
中科院分区：
文献类型：
--
作者：
Wilson-Heid, Alexander E.;Qin, Shipin;Beese, Allison M.
对添加法制备的奥氏体316L不锈钢L激光粉床熔化处理后的多轴大变形延性断裂行为进行了实验测量。利用五种不同应力状态(剪切、剪切/拉伸组合加载状态、平面应变拉伸和单轴拉伸)下两个方向的试验数据来校准和验证各向异性塑性和断裂模型，并使用不同的试件几何形状来探测塑性和断裂。剪切软化被认为是由于高初始位错密度和亚微米胞状结构在材料中形成剪切带所致，在剪切主导试验中观察到了剪切软化，并采用各向异性塑性模型中的剪切损伤准则进行了模拟。采用实验和计算相结合的方法，对两种样品取向的各向同性和各向异性Hosford-Coulomb和修正的Mohr-Coulomb韧性断裂模型进行了标定。校正后的各向异性霍斯福德-库仑断裂模型最好地反映了L-PBF316L的应力状态依赖性和各向异性破坏行为。(C)2020 Acta Materialia Inc.由爱思唯尔有限公司出版。版权所有。
The multiaxial large deformation and ductile fracture behavior of laser powder bed fusion (L-PBF) additively manufactured austenitic 316L stainless steel was experimentally measured. Data from tests in two orientations, under five dissimilar stress states (shear, combined shear/tension loading states, plane strain tension, and uniaxial tension) were used to calibrate and validate anisotropic plasticity and fracture models, with different specimen geometries used to probe plasticity versus fracture. Shear softening, hypothesized to be due to shear band formation in the material due to high initial dislocation density and sub-micron cellular structures, was observed in shear dominated tests, and modeled through the adoption of a shear damage criterion in an anisotropic plasticity model. Using a combined experimental and computational approach, isotropic and anisotropic Hosford-Coulomb and modified Mohr-Coulomb ductile fracture models were calibrated for both sample orientations. The calibrated anisotropic Hosford-Coulomb fracture model best captures the stress state dependent and anisotropic failure behavior of L-PBF 316L. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.