HOMOGENIZATION OF MECHANICAL PROPERTIES FOR ADDITIVELY MANUFACTURED PERIODIC LATTICE STRUCTURES CONSIDERING JOINT STIFFENING EFFECTS

This paper presents a homogenization approach for estimating the mechanical properties of periodic lattice structures; it is based on semi-rigid joint frame elements, and it takes into account joint stiffening effects. Geometrical degradation that arises from the additive manufacturing process is considered and integrated into a homogenization procedure that uses structural element parameters derived from a frame element with semi-rigid joints. The effective values of the structural parameters are calculated from a novel as-fabricated model describing an additively fabricated strut and are incorporated into proposed semi-rigid frame elements. The semirigid joint frame element is integrated into a discrete homogenization process. This paper reports the results of parametric studies that compare the effective structural parameters and the estimated mechanical properties to study the impacts of joints and geometric degradation due to additive manufacturing. The results of the proposed approach are compared with previous homogenization approaches, and show that the proposed method provides more accurate estimates.