Effect of elevated temperature on the out-of-plane compressive properties of nickel based pyramidal lattice truss structures with hollow trusses

In this study, the effect of elevated temperatures on the out-of-plane properties of nickel based pyramidal lattice truss structures with hollow trusses were investigated through theoretical analysis, experimental measurements and numerical prediction. It is found that, with the increase of temperature from 25 °C to 450 °C, the compressive strength, compressive modulus and energy absorption capacity of the sandwich structures fabricated via SLM additive manufacturing decrease by 37.98%, 33.25% and 38.36%, respectively. The theoretically predicted failure modes and compressive strength of the hollow lattice truss cores are in well agreement with experimental measurements and numerical predictions. Comparison with competing lightweight sandwich constructions reveals that the nickel based pyramidal lattice truss structure with hollow truss exhibits superiority in the specific strength under high temperature.