Abstract:Porous CoCrNi MEA with porosity of 60.6% -78.1% and pore size of 1.8 -2.4mm were prepared by powder sintering-dissolution method. The pore distribution is uniform and the metallurgical bonding is good. The dynamic compression test results show that the material has a significant strain rate strengthening effect, and the impact resistance is the best at 500s-1 strain rate. The yield strength increases by 52.8% (22.9 MPa to 35.0MPa) with the increase of strain rate from 200s-1 to 800s-1. The dynamic yield strength increases by 25% compared with the quasi-static yield strength. The energy absorption value reaches 35.4 ~14.5MJ/m3 (6.6% ~ 14.0% higher than the quasi-static), and the maximum ideal energy absorption efficiency is close to 0.9. At the same time, under the condition of low temperature (-100°C), the elastic modulus and platform stress are increased by 2.4% ~10.5% and 2.5% ~9.8%, respectively, compared with room temperature. The energy absorption value is 41.3 ~15.2MJ/m3, which is twice that of magnesium alloy foam, and the maximum ideal energy absorption efficiency remains 0.8. In summary, the porous CoCrNi MEA has both dynamic strengthening and low-temperature strengthening characteristics, and has good energy absorption capacity and high ideal energy absorption efficiency, showing significant application potential in the field of actual working conditions and extreme environments.