Investigation of Mechanical Properties and in vitro Corrosion Rate of Open-‎Cell Cast Magnesium Foams ‎

In this study, open-cell magnesium foams with irregular and spherical morphology in different sizes and amounts of porosity were produced using the melt infiltration method into a NaCl space holder material. After determining the amount of closed porosity, the effects of morphology and porosity on the mechanical properties of the produced foams were investigated. Structure evaluation of the foams showed that more than 93% of the cells of the produced foams have open porosity and the foams with the irregular cells have a higher amount of the closed cells. Also, the amount of porosity of the foams varied from 54 to 62%. The results of the compression test showed that with increasing the porosity percentage, mechanical properties such as Young's modulus of the foams (E*) and stress of the plateau zone (s*PL) decreased. Also, the irregular cell foams have a higher energy absorption than the spherical cell foams due to the wider plateau zone in the stress-strain curve. The in vitro corrosion rate of the foams was also studied by immersion test in the simulated body fluid (SBF) for two foams specimens with spherical cell morphology and the lowest closed cell amount. The results of the corrosion test have also shown that the size of the porosity of the foams can affect the corrosion rate, so that the smaller cell size foams had higher corrosion rate than the larger cell size foams.