GrainPaint: A multi-scale diffusion-based generative model for microstructure reconstruction of large-scale objects
Nathan Hoffman, Cashen Diniz, Dehao Liu, Theron Rodgers, Anh Tran, Mark Fuge
TL;DR
GrainPaint addresses the challenge of generating large-scale, realistic microstructures for CAD-scale objects by leveraging diffusion-based outpainting (RePaint) to overcome fixed-generation-size limitations of previous ML approaches. The method is trained on SPPARKS-generated 3D grain datasets and uses a 3D U-Net with a multi-stage parallelization to assemble arbitrary geometries. It demonstrates qualitative similarity to SPPARKS across CAD-referenced objects and quantitative agreement for isotropic microstructures, and reveals some gaps for anisotropic cases. The work suggests GrainPaint can accelerate scale-appropriate microstructure generation for computationally expensive processes and CAD-driven applications, with opportunities for conditioning and multi-scale extensions.
Abstract
Simulation-based approaches to microstructure generation can suffer from a variety of limitations, such as high memory usage, long computational times, and difficulties in generating complex geometries. Generative machine learning models present a way around these issues, but they have previously been limited by the fixed size of their generation area. We present a new microstructure generation methodology leveraging advances in inpainting using denoising diffusion models to overcome this generation area limitation. We show that microstructures generated with the presented methodology are statistically similar to grain structures generated with a kinetic Monte Carlo simulator, SPPARKS.
