​​​​​​​We were pleased to have David Najera from ATA Engineering present at the 2022 SIMULIA Santa Clara Regional User Meeting, June 22, 2022.

Abstract: Cost-effective and rapid implementation of additive manufacturing (AM) for complex parts in critical applications is currently impeded by a lack of predictive insights into the physics of AM processes and their impact on part performance and reliability. To address this challenge, a complete thermal mechanical-material modeling and simulation workflow was developed that uses automated data mapping and translation tools to integrate part-level print simulations, probabilistic grain growth models, and crystal plasticity homogenization techniques to efficiently predict metallic part residual stresses, net shape, and strength. Thermal-mechanical fields during printing are simulated using the finite element analysis code Abaqus. The as-printed grain microstructure is predicted from Abaqus thermal history results using the kinetic Monte Carlo code SPPARKS. The homogenized microstructural response is determined with the crystal plasticity spectral solver DAMASK. Dimensionality reduction is performed by employing a K-means algorithm to cluster regions of similar thermal histories in a part for spatially varying assignment of mechanical properties. Finally, process simulation insights (residual stresses, material properties) are embodied in a part-level Abaqus finite element model representing the as-built condition. This workflow has been demonstrated and partially validated via prediction of the tensile response of two sets of 316L cylindrical test coupons with varying printing paths and manufactured with a directed energy deposition process, which were presented in Yadollahi et al. [Materials Science and Engineering: A 664, 2015: 171–83]. The results show a path toward a foundational physics-based simulation toolset for part performance characterization that leverages state-of-the-art tools available to industry.​​​​​​​

Biography: David Najera is a project engineer at ATA Engineering in San Diego. His work is focused on material characterization and nonlinear dynamics.

RUM2022 ​​​​​​​RUM2022-SantaClara Abaqus ​​​​​​​