jaue2016120: Effect of Recycling Oyster Shells in Pure Magnesium

Abstract

Increasing application of magnesium alloys has been used in many industries because these alloys have high specific properties. Unfortunately, the use of magnesium alloys is limited due to their low oxidation resistance. In recent research, it was suggested that addition of CaO was effective to increase the oxidation resistance of magnesium alloys. CaO can be extracted from CaCO3 which is main component of oyster shells. Some of oyster shells which are generated enormous amounts every year in Korea are recycled but most of them are buried and discarded. Therefore, it is absolutely necessary to recycle oyster shells. 
Oyster shells were fully segregated to CaO at 765℃. Microstructure observation was conducted using an optical microscopy. In order to investigate the effect of CaO on oxidation of pure magnesium, oxidation test was conducted by using a thermogravimetric analyzer (TGA). Heating rate was 10℃/min and it was performed until 800℃ under ambient atmosphere.
A change in the oxidation of magnesium was observer by adding recycling oyster shells. It was observed that weight gain was decreased about 18% about with increasing amounts of CaO addition. It means that CaO had enough influence to oxidation resistance of pure magnesium.