Laser powder bed fusion of complex metal lattice metamaterials: a structurally robust holistic design approach

The increasing demand for lightweight, high-strength, and multifunctional materials is driving the rapid development of complex metal lattice metamaterials through additive manufacturing (AM). However, fabrication challenges often hinder their full design potential. This study presents an easy-to-apply finite element (FE)-based design framework, governed by six fundamental equations, offering a holistic lattice design approach that meets the manufacturability requirements of laser powder bed fusion AM. By integrating global and natural coordinate systems with shape functions, the method enables precise lattice node positioning and accurate strut inclination angle calculations, essential for determining inclined strut diameter using an established model. Demonstrated with complex, bespoke Ti–6Al–4V lattices, the framework achieves high design-fabrication consistency, yielding robust structures with desirable mechanical properties. This versatile framework efficiently designs complex lattices with arbitrary boundary conditions, advancing design, fabrication, and performance in a synchronized manner.