Effect of temperature on compressive behavior of additively manufactured CoCrNi alloy lattice-core sandwich structure

Design for safety of additively manufactured sandwich structure remains challenging for accommodating harsh service environments with a wide range of temperatures. To investigate temperature effect on compressive performance of additively manufactured CoCrNi alloy sandwich structure, the quasi-static out-of-plane compression performance of such sandwich structures with hollow pyramidal lattice core were experimentally and numerically studied at a wide ambient temperature range from −196 ℃, 25 ℃, 400 ℃, and 600 ℃. Results indicated that, with increasing of temperature, the compressive strength and the absorbed energy performances of sandwich structures decrease to 40.71 % and 46.3 %, respectively, which are in well agreement with numerical prediction. Numerical results revealed that the compressive strength and energy absorption performance of sandwich structure increased as the normalized geometric parameters d/l and t_c/d increased. Moreover, compared with aluminum alloy, nickel based alloy, titanium alloy and multi-principle element alloys architecture materials with similar service temperature, CoCrNi medium entropy alloy hollow pyramidal lattice has outstanding advantages in being used as load-bearing components over a wide temperature range.