Preparation And Characterization Of Bioceramic/magnesium Composites

Magnesium is a light-weight metal with a density of 1.74 g/cm~3, almost the same as the nature human bone (1.75 g/cm~3), having high specific strength and high specific rigidity. In addition, it has excellent biocompatibility and biodegradability, however, magnesium does't have bioactivity. 45S5 bioactive glass and hydroxyapatite have favorable bioactivity and biodegradability. Exploring magnesium and 45S5 bioactive glass or hydroxyapatite can realize the complementary advantages, achieving the purpose of enhancing the mechanical properties and maintaining biological activity. By now, there is no research about 45S5 bioactive glass/magnesium composites. While the hydroxyapatite/magnesium composites are mostly prepared by conventional powder metallurgy method using the thermal radiation heating method with the disadvantages of slow heating rate, long sintering time, energy consumption, polluting environment.In this study, for the first time, 45S5 bioactive glass/magnesium composites were prepared by powder metallurgy method. Hardness, compressive mechanical property, bending mechanical property and corrosion resistance of the 45S5 bioactive glass/magnesium composites were investigated. It is found that the addition of 45S5 bioactive glass can improve hardness and corrosion resistance of the materials, but density, compressive strength and bending strength decrease. With the extension of the sintering time, density, compressive strengths, bending strength and corrosion resistance of magnesium and composites are improved.For the first time, this study prepares the hydroxyapatite/magnesium composites by microwave sintering. Hardness, compressive mechanical property, bending mechanical property, corrosion resistance and biocompatibility of the hydroxyapatite/magnesium composites were investigated. Compared with conventional sintering method, microwave sintering method has the advantages of rapid heating rate, short sintering time, short preparation period, low power consumption, no pollution and can meet the requirements of developing economical and environmental protection society. At the same time preparation of hydroxyapatite/magnesium composite made by microwave sintering has good mechanical properties and biocompatibility to meet the mechanical and biological performance requirements of the human bone tissue. Therefore microwave has a good prospect.