Investigation of microstructure and mechanical properties of magnesium calcium alloys produced by mechanical alloying and hot pressing

Powder metallurgy (PM) is a production method that provides better advantages to the producers comparing to the other methods. Biodegradable Mg alloys have superiorities compared to iron and zinc alloys. Mg-based alloys are still inhibited mainly by their high degradation rates and consequent loss in mechanical integrity. The broad studies in this subject are to increase the mechanical properties and corrosion performance. In this study, in order to predict the mechanical properties of biodegradable Mg and Ca which are produced with the powder metallurgy method, Mg-xCa alloys with high mechanical properties are developed by using statistical model CCD design, anova analysis and regression equation indicated that the model was accurate. In this study, the powder Mg and Ca have put to the process of alloying with different period of times. Grain sizes of the powders are measured and they have been analyzed for SEM EDS, XRD. Powders are pressed by a uniaxial hot compression in a vacuumed environment under argon gas in 46MPa pressure in different temperatures they have been sintered and sampled in blocks. Mg-xCa alloys have been analyzed comparatively for their microstructures, mechanical properties, pressure endurance, density rates and stiffness. It has been observed that secondary phase Mg2Ca increases with the increasing rate of Ca. The measured values of Mg-xCa alloys are 251MPa for compressive strength, 146 Brinel for hardness, and 1.7 g/cm3 for density. Mg-xCa alloys have performed much superior compared to pure Mg.