Corrosion Behavior of Magnesium Based Foam Structure in Hank’s Solution

Metal foam are a new class of materials with promising applications and a unique combination of physical, chemical and mechanical properties. The purpose of biodegradable implants is to support tissue regeneration and healing in a specific application by material degradation and concurrent implant replacement through the surrounding tissue. Magnesium alloys are expected to be degraded in the body and its corrosion products not deleterious to the surrounding tissue. In the present study, the foam metal were manufactured via powder metallurgy with different variation of sintering temperature and TiH2 used as a foaming agent which are added to Mg-1Ca-3Zn alloy as much 3 persenwt TiH2. Variation sinter temperature were 500, 550 and 600°C with constant holding time of 5 hours. It’s critical that the sintering temperature are carefully selected in consideration of their corrosion behavior. This paper reports the study of the behavior of the Mg-Ca-Zn alloy metal foam which evaluated by SEM, EDX, and electrochemical corrosion test in Hank’s solutions. After exposure, the SEM result of Mg-Ca-Zn-3TiH2 to Hank’s solution, a volcano-like structure is formed. The steams of H2 bubbles form at local sites on the Mg alloy surface where electrochemical reactions are taking place, leading to the peculiar structure with around shape and often with a hole in the centre. The corresponding EDS result maps reveal enrichment of O, Ca, P and Mg as corrosion product. Potentiodynamic polarisation experiments conducted at 37°C and pH 7.4 indicated the increased biodegradation rates resulted from porous structure of foam samples. Corrosion rate in 500oC sintering temperature were 1,99 mmpy with I corr 87,3E-6 A/cm2, corrosion rate in 550oC sintering temperature were 2,16 mmpy with I corr 94,4 E-6 A/cm2 and rate in 600oC sintering temperature were 2,41 mmpy dengan I corr 105E-6 A/cm2. The results showed that the increasing of sintering temperature could influence the corrosion resistance of Mg alloy. The International Conference on Advanced Materials Science and Technology 2016