TY - JOUR

T1 - Predicting residual stresses in SLM additive manufacturing using a phase-field thermomechanical modeling framework

AU - Ali, Baharin

AU - Heider, Yousef

AU - Markert, Bernd

N1 - Funding Information: The first author would gratefully acknowledge the German Academic Exchange Service (DAAD) for the support via the doctoral research grant number 57214224 . The support from the Iraqi Ministry of Oil is also gratefully acknowledged.

PY - 2024/1/5

Y1 - 2024/1/5

N2 - Additive manufacturing (AM) of metallic components has recently become a viable option for series production. In this, the powder of various metallic materials such as steel and aluminum can be processed layer-by-layer to produce dense parts with excellent properties. One of the major challenges in this process is the occurrence of residual stresses, which negatively affect the strength and functionality of the produced components. Understanding the mechanism of distribution of these stresses and the detrimental deformations is one of the main themes covered in this work. In the numerical treatment with the finite element method, a phase-field model (PFM) for phase-change materials is utilized together with a thermo-elastoplastic model to simulate the multi-layer AM process and to evaluate the occurring residual stresses. Using the PFM allows tracking the diffusive melting front and, thus, distinguishing between the melted (soft) and the unmelted (hard) states of the material. One of the novel contributions is the definition of a phase-field history variable, which can capture the irreversible process of metallic powder melting. Additionally, phase-field-dependent material properties are proposed. The coupled governing equations are solved in the open-source FE package FEniCS Project, where three-dimensional initial-boundary-value problems are introduced and the results are compared with reference data from the literature.

AB - Additive manufacturing (AM) of metallic components has recently become a viable option for series production. In this, the powder of various metallic materials such as steel and aluminum can be processed layer-by-layer to produce dense parts with excellent properties. One of the major challenges in this process is the occurrence of residual stresses, which negatively affect the strength and functionality of the produced components. Understanding the mechanism of distribution of these stresses and the detrimental deformations is one of the main themes covered in this work. In the numerical treatment with the finite element method, a phase-field model (PFM) for phase-change materials is utilized together with a thermo-elastoplastic model to simulate the multi-layer AM process and to evaluate the occurring residual stresses. Using the PFM allows tracking the diffusive melting front and, thus, distinguishing between the melted (soft) and the unmelted (hard) states of the material. One of the novel contributions is the definition of a phase-field history variable, which can capture the irreversible process of metallic powder melting. Additionally, phase-field-dependent material properties are proposed. The coupled governing equations are solved in the open-source FE package FEniCS Project, where three-dimensional initial-boundary-value problems are introduced and the results are compared with reference data from the literature.

KW - Additive manufacturing

KW - FEniCS Project

KW - Phase-field modeling

KW - Residual stresses

KW - Selective laser melting

KW - Thermo-elastoplastic model

UR - http://www.scopus.com/inward/record.url?scp=85175542392&partnerID=8YFLogxK

U2 - 10.1016/j.commatsci.2023.112576

DO - 10.1016/j.commatsci.2023.112576

M3 - Article

AN - SCOPUS:85175542392

VL - 231

JO - Computational materials science

JF - Computational materials science

SN - 0927-0256

M1 - 112576

ER -