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arXiv · 2111.01995

A spiral laser scanning routine for powder bed fusion inspired by natural predator-prey behavior

Abstract

Additive manufacturing by laser powder bed fusion (LPBF) offers material versatility, capability for complex geometries, and control of mechanical properties and microstructure. However, achieving high-quality output requires process parameters that consider both local and global thermal gradients. Here, we propose a new scan pattern for mitigating part quality issues caused by non-uniform heating and cooling. A nature-inspired design method is employed to derive a spiral pattern stemming from the predator-prey behavior, and a power optimization routine is applied to maintain constant melt pool depth. Comparing simulated thermal histories for the spiral pattern to well-established zig-zag and helix scan patterns, we propose that the spiral pattern significantly reduces the spatial variation of temperature across the scan area, while a larger area remains above a specified threshold temperature at the end of the scan. Consequently, the spiral pattern is promising for LPBF of crack-prone materials, and for future optimization of LPBF overall.

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BibTeXRIS

Suh In Kim, A. John Hart. 2021-11-03. A spiral laser scanning routine for powder bed fusion inspired by natural predator-prey behavior. https://arxiv.org/abs/2111.01995

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