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Magnesium alloys have good mechanical properties and biocompatibility , while both biodegradable and therefore is expected to develop into a new generation of bone fixation materials . However, the existing commercial magnesium alloy corrosion too fast , its corrosion resistance needs to be improved . This study was prepared Mg-2.5wt% Zn alloy and a Mg - XWT % a Zn- 0.5wt % Zr series alloy ( X = 2.5,3.5,4.5 ) . Mechanical properties in vitro tests and corrosion degradation test , analysis of the influence of the of adding Zr elements, and the Zn content in the Mg-Zn-Zr alloys ; selected and on this basis the optimal components Mg-2.5wt% Zn-0.5wt% Zr the alloy subjected to surface treatment for the base body , the preparation of composite materials , the results showed that: 1. adding Zr elements can significantly refinement of Mg-Zn alloy grains and improve the strength, ductility and hardness of the alloy , reduce the in vitro degradation rate of the magnesium alloy . 2 Mg - XWT % Zn - 0.5wt% Zr series alloy (x = 2.5,3.5,4.5) , tensile strength and hardness , increase with the increase of Zn content , but the ductility and corrosion resistance decreased significantly ; wherein Mg - 2.5wt % Zn - 0.5 wt % Zr alloy ultimate tensile strength of 305 MPa, elongation of 21.0% , the corrosion current density of 2.10μA/cm 2 < / sup> , the performance is better than the other groups sub - Mg-Zn-Zr alloys . Coating deposition by HF acid treatment , and β-TCP , in Mg - 2.5wt % Zn - 0.5wt % Zr alloy surface 0.5μm of MgF 2 conversion film are respectively formed of the β- and 5μm TCP coatings, the corrosion resistance of the alloy significantly improved. Added nano- β-TCP enhanced body is evenly distributed in the Mg-Zn-Zr alloy matrix refinement significantly improved mechanical and corrosion resistance of magnesium alloy .
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