Deep-Learned Generators of Porosity Distributions Produced During Metal Additive Manufacturing

TL;DR

This paper introduces a novel deep learning framework combining GANs and scattering transforms to generate realistic porosity distributions in metal additive manufacturing, addressing limitations of previous models.

Contribution

It presents a new method that models boundary-dependent and sparse porosity distributions, improving synthetic microstructure generation for AM parts.

Findings

Generated porosity distributions match experimental data statistically.

The method accurately reproduces pore geometries and surface roughness.

The approach outperforms previous models in capturing boundary-dependent porosity.

Abstract

Laser Powder Bed Fusion has become a widely adopted method for metal Additive Manufacturing (AM) due to its ability to mass produce complex parts with increased local control. However, AM produced parts can be subject to undesirable porosity, negatively influencing the properties of printed components. Thus, controlling porosity is integral for creating effective parts. A precise understanding of the porosity distribution is crucial for accurately simulating potential fatigue and failure zones. Previous research on generating synthetic porous microstructures have succeeded in generating parts with high density, isotropic porosity distributions but are often inapplicable to cases with sparser, boundary-dependent pore distributions. Our work bridges this gap by providing a method that considers these constraints by deconstructing the generation problem into its constitutive parts. A framework is introduced that combines Generative Adversarial Networks with Mallat Scattering Transform-based autocorrelation methods to construct novel realizations of the individual pore geometries and surface roughness, then stochastically reconstruct them to form realizations of a porous printed part. The generated parts are compared to the existing experimental porosity distributions based on statistical and dimensional metrics, such as nearest neighbor distances, pore volumes, pore anisotropies and scattering transform based auto-correlations.