Murgas Brayan, Stickel Joshua, Brewer Luke, Ghosh Somnath
Department of Civil & Systems Engineering, Johns Hopkins University, Baltimore, MD, USA.
Department of Materials Science & Engineering, University of Alabama, Tuscaloosa, Al, USA.
Nat Commun. 2024 Nov 1;15(1):9441. doi: 10.1038/s41467-024-53865-3.
Creating statistically equivalent virtual microstructures (SEVM) for polycrystalline materials with complex microstructures that encompass multi-modal morphological and crystallographic distributions is a challenging enterprise. Cold spray-formed (CSF) AA7050 alloy containing coarse-grained prior particles and ultra-fine grains (UFG) and additively manufactured (AM) Ti64 alloys with alpha laths in beta substrates. The paper introduces an approach strategically integrating a Generative Adversarial Network (GAN) for multi-modal microstructures with a synthetic microstructure builder DREAM.3D for packing grains conforming to statistics in electron backscatter diffraction (EBSD) maps for generating SEVMs of CSF and AM alloy microstructures. A robust multiscale model is subsequently developed for self-consistent coupling of crystal plasticity finite element model (CPFEM) for coarse-grained crystals with an upscaled constitutive model for UFGs. Sub-volume elements are simulated for efficient computations and their responses are averaged for overall stress-strain response. The methods developed are important for image-based micromechanical modeling that is necessary for microstructure-property relations.
为具有复杂微观结构(包括多模态形态和晶体学分布)的多晶材料创建统计等效的虚拟微观结构(SEVM)是一项具有挑战性的工作。冷喷涂成型(CSF)的AA7050合金包含粗晶粒原始颗粒和超细晶粒(UFG),以及在β基体中具有α板条的增材制造(AM)Ti64合金。本文介绍了一种策略性地整合用于多模态微观结构的生成对抗网络(GAN)和用于填充符合电子背散射衍射(EBSD)图统计数据的晶粒的合成微观结构构建器DREAM.3D的方法,以生成CSF和AM合金微观结构的SEVM。随后开发了一个强大的多尺度模型,用于将粗晶粒晶体的晶体塑性有限元模型(CPFEM)与UFG的尺度相关本构模型进行自洽耦合。对亚体积单元进行模拟以实现高效计算,并对其响应进行平均以获得整体应力-应变响应。所开发的方法对于基于图像的微观力学建模非常重要,而微观力学建模对于微观结构-性能关系是必不可少的。