Effects of porosity and pore size on the compressive properties of closed-cell Mg alloy foam

In our current work, AZ31 magnesium alloy foams with closed-cell were successfully fabricated by melt foaming method using Ca and CaCO3 as thickening and blowing agent, respectively. The influences of porosity and pore size on the quasi-static compressive properties of the foams were systematically investigated. The results showed that the yield strength, energy absorption capacity and ideality energy absorption efficiency were decreased with the increase in porosity. However, specimens with porosities of 60%, 65% and 70% possessed similar total energy absorption capacity and ideality energy absorption efficiency. Meanwhile, experimental results showed that mean plateau strength of the foams was increased first and then decreased with increase in mean pore size. In addition, energy absorption capacities were almost the same in the initial stage, while the differences were obvious in the middle stage. From the engineering point of view, the specimens with mean pore size of 1.5 mm possess good combination of mean plateau strength and energy absorption characteristics under the present conditions. Copyright 2013, National Engineering Research Center for Magnesium Alloys of China, Chongqing University. Production and hosting by Elsevier B.V. Open access under CC BY-NC-ND license.