Abstract The solidification microstructures of plain and inoculated 6061 aluminum builds manufactured with gas metal arc-directed energy deposition were studied with a combination of models and experiments. Electron back-scatter diffraction (EBSD) showed that the plain 6061 build had large, columnar grains with intergranular solidification cracking, while the inoculated build had a near-equiaxed, fine grain microstructure with no solidification cracks. By combining EBSD and energy dispersive spectrometry, the inoculated build has been shown to have exhibited globular growth while the non-inoculated build displayed a dendritic microstructure. A combination of heat transfer and modified grain morphology models were employed to predict the solidification morphology of the 6061 builds, which closely matched experimental results. A modification is proposed to the criterion marking the transition from globular to dendritic growth that better matches experimental results in this work. The results of this study are expected to provide improved methods to predict solidification microstructure for the development of new materials and processing parameters for additive manufacturing.
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AlloyGAN: Domain-Promptable Generative Adversarial Network for Generating Aluminum Alloy Microstructures
The global metal market, expected to exceed $18.5 trillion by 2030, faces costly inefficiencies from defects in alloy manufacturing. Although microstructure analysis has improved alloy performance, current numerical models struggle to accurately simulate solidification. In this research, we thus introduce AlloyGAN - the first domain-driven Conditional Generative Adversarial Network (cGAN) involving domain prior for generating alloy microstructures of previously not considered chemical and manufactural compositions. AlloyGAN improves cGAN process by involving prior factors from solidification reaction to generate scientifically valid images of alloy microstructure given basic alloy manufacturing compositions. It achieves a faster and equally accurate alternative to traditional material science methods for assessing alloy microstructures. We contribute (1) a novel Alloy-GAN design for rapid alloy optimization; (2) unique methods that inject prior knowledge of the chemical reaction into cGAN-based models; and (3) metrics from machine learning and chemistry for generation evaluation. Our approach highlights the promise of GAN-based models in the scientific discovery of materials. AlloyGAN has successfully transitioned into an AIGC startup with a core focus on model-generated metallography. We open its interactive demo at: https://deepalloy.com/
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- Award ID(s):
- 2021871
- PAR ID:
- 10523430
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- Proceedings
- ISSN:
- 1946-0759
- ISBN:
- 979-8-3503-4534-6
- Page Range / eLocation ID:
- 1649 to 1655
- Subject(s) / Keyword(s):
- Metals Generative adversarial networks Chemical reactions Aluminum alloys Manufacturing Numerical models Microstructure
- Format(s):
- Medium: X
- Location:
- Jacksonville, FL, USA
- Sponsoring Org:
- National Science Foundation
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