Experimental investigation and numerical modeling of laser powder bed fusion process-induced angle-dependent defects in strut-based lattice structure

The emergence of additive manufacturing technology has enabled the fabrication of advanced structures with intricate geometric topologies. However, additive manufacturing induces geometric defects in as-printed structures which may result in deviation from the parent material's properties. The defects and impaired material properties greatly influence the performance of the fabricated structure. In this paper, the effect of build angle is investigated. The angle-dependency for the geometric defect distribution characteristics is verified through X-ray tomography. The mathematical relationship between the parent material's properties and the build angle is established. A numerical model is developed for predicting the mechanical performance of laser powder bed fusion fabricated lattice structures proposed by using the experimental results. The positioning geometric defects are introduced into this model to achieve higher predicting accuracy. This work proposes a reliable and low-cost numerical analysis method based on the angle dependence and helps in predicting the mechanical performance of additive-manufactured complex three-dimensional lattice structures.