Superimpositional design of crystallographic textures and macroscopic shapes via metal additive manufacturing—Game-change in component design

Abstract

This study demonstrates the control of the crystalline orientation through metal additive manufacturing, enabling the development of component design guidelines that incorporate the inherent anisotropy of the mechanical properties (e.g., Young's modulus) in crystalline materials. We, for the first time, successfully fabricated a <111>//build direction (BD)-oriented single-crystalline-like texture in an alloy with a cubic crystal structure via laser powder bed fusion (LPBF) and completed a series of three single-crystalline-like microstructures with <001>, <011>, and <111>//BD orientations in a single material. The <001> and <111> directions exhibited the lowest and highest Young's moduli, respectively, demonstrating a wide range of control over the anisotropy of the mechanical properties of the product. To achieve a <111>//BD-oriented single-crystalline-like texture, a novel three-layer cyclic strategy of “uni”directional laser scanning at 120° angular intervals was developed by considering the easy growth direction and crystal symmetry. To the best of our knowledge, no previous study has reported this unique strategy. By superimposing the realized <111> orientation and shape-based anisotropy, products exhibiting high Young's modulus anisotropy, which cannot be expressed by shape and texture alone, were obtained via the LPBF single process. This achievement holds promise for the realization of a new component design guideline that integrates texture (mechanical properties) design for each internal location—modifiable through scanning strategies—with traditional shape optimization techniques typically used in computer-aided design. This approach enables tailored mechanical performance through optimized design strategies.