TY - JOUR
T1 - Process-induced defects and failure mechanisms in metal additive manufacturing : A mesoscale coupled damage and plasticity modeling and X-ray computed tomography approach
AU - Nafar Dastgerdi, Jairan
AU - Lotf Yasouri, Milad
AU - Remes, Heikki
N1 - Publisher Copyright:
© 2024 The Author(s)
PY - 2025/2/1
Y1 - 2025/2/1
N2 - This study aims to clarify the effect of process-induced defects on the damage behavior of metal additive manufactured (AM) components at the mesoscale using a numerical approach based on the coupled continuum damage mechanics (CDM) and plasticity model to provide a guideline for assessing the strength of metal AM components by considering defects’ features and their interaction. For this purpose, the finite element (FE) simulations, instantiated from the real microstructures captured by the initial X-ray computed tomography (XCT) imaging from the intact sample at several locations around the specimen, are deployed to reveal the activity of multiple failure mechanisms. FE simulations precisely identify the sites and the mechanism of ductile failure compared to experimentally observed sites of damage initiation and evolution based on XCT imaging in a temporal domain during tensile loading for the AM 316L stainless steel sample. It is found that the intervoid necking mechanism mainly controls the interaction of internal and surface defects and internal defects in close proximity. Then, the other intervoid sheeting and intervoid shearing mechanisms are active sequentially during the failure process. A systematic investigation is carried out to first reveal the defect-property relationships in damage progression and deformation patterns of these materials and then to define acceptance limits for internal and surface defects’ shape, size, distribution, and proximity to each other, identifying when the imperfections become defects. The results of this study can pave the road to overcoming the limitation of more widespread use of metal AM materials in different industries by providing a validated numerical approach to optimizing process parameters based on understanding the interaction between different process parameters, resultant internal and surface defects, and damage behavior of these materials under service loading.
AB - This study aims to clarify the effect of process-induced defects on the damage behavior of metal additive manufactured (AM) components at the mesoscale using a numerical approach based on the coupled continuum damage mechanics (CDM) and plasticity model to provide a guideline for assessing the strength of metal AM components by considering defects’ features and their interaction. For this purpose, the finite element (FE) simulations, instantiated from the real microstructures captured by the initial X-ray computed tomography (XCT) imaging from the intact sample at several locations around the specimen, are deployed to reveal the activity of multiple failure mechanisms. FE simulations precisely identify the sites and the mechanism of ductile failure compared to experimentally observed sites of damage initiation and evolution based on XCT imaging in a temporal domain during tensile loading for the AM 316L stainless steel sample. It is found that the intervoid necking mechanism mainly controls the interaction of internal and surface defects and internal defects in close proximity. Then, the other intervoid sheeting and intervoid shearing mechanisms are active sequentially during the failure process. A systematic investigation is carried out to first reveal the defect-property relationships in damage progression and deformation patterns of these materials and then to define acceptance limits for internal and surface defects’ shape, size, distribution, and proximity to each other, identifying when the imperfections become defects. The results of this study can pave the road to overcoming the limitation of more widespread use of metal AM materials in different industries by providing a validated numerical approach to optimizing process parameters based on understanding the interaction between different process parameters, resultant internal and surface defects, and damage behavior of these materials under service loading.
KW - Additive manufacturing
KW - Damage
KW - Defect
KW - Finite element modeling
KW - X-ray computed tomography
UR - http://www.scopus.com/inward/record.url?scp=85210729856&partnerID=8YFLogxK
U2 - 10.1016/j.engfailanal.2024.109123
DO - 10.1016/j.engfailanal.2024.109123
M3 - Article
AN - SCOPUS:85210729856
SN - 1350-6307
VL - 168
JO - Engineering Failure Analysis
JF - Engineering Failure Analysis
M1 - 109123
ER -