Comparison of deformation characteristics and energy absorption of additively manufactured superalloys lattice structures under quasi-static compression

Nickel-based superalloy lattice structures exhibit broad application prospects in the aerospace field. In this research, three lattice structures (BCC, 3ATC, and P-TPMS) were fabricated using IN718 and IN625 through SLM techniques, followed by quasi-static compression tests and numerical simulations. Among the three lattice structures made from the same material, the yield strength follows the order: P-TPMS > BCC > 3ATC. For the lattice structures made by IN718, the BCC and 3ATC structures featured limited load-bearing capacity and were subject to premature failure, while the P-TPMS structure exhibited the best overall performance, with a yield strength of 66.1 MPa and specific energy absorption of 22.1 J/g. However, this came at the cost of extensive structural damage. Benefiting from the excellent toughness of IN625, all lattice structures fabricated with this material were capable of achieving densification. Among them, the BCC and P-TPMS structures demonstrated no significant damage, making them ideal for applications involving large deformations. Meanwhile, the 3ATC structure showed damage and poorer stability. The matrix material and topology significantly influence the load-bearing capacity, deformation, and damage characteristics of lattice structures. Therefore, selecting appropriate materials and structures according to specific application requirements is crucial.