A Thermal-Fluid-Solid Modeling Approach for Quantifying Residual Stresses Linked to Defects in Additive Manufacturing

Computational models are a useful and established tool for qualification of additively

manufactured (AM) components because they can allow coupling between the multiphysics

environments. During AM printing, power settings or path directions of the laser can cause

defects such as pores which may compromise the mechanical integrity of a printed part. In this

work, a thermal-fluid-solid finite element analysis model is built and used to predict the residual

stresses surrounding a pore defect. A thermal-fluid model is first run to quantify the temperature

environment and pore geometry as consequence of the laser interaction, deposition, and fluid

flow. This model is then one-way coupled to an implicit solid mechanics model which quantifies

the material residual stress. Utilizing this workflow offers a high-fidelity multiphysics solution

that can be analyzed and tested in mechanical environments. This work provides valuable results

for qualifying the effects of defects, and associate residual stresses, on structural performance of

AM components.

Sandia National Laboratories is a multi-mission laboratory managed and operated by

National Technology & Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of

Honeywell International, Inc., for the U.S. Department of Energy’s National Nuclear Security

Administration under contract DE-NA0003525.