Preparation And Properties Research Of Biomedical Material MgZnCa Alloys

There is two main aspects involved in the work. The first is to prepare thediameter of3.0mm Mg-Zn-Ca ternary eutectic（E₁,E₂,E₄and E₅） alloys rods by coppermold suction casting method, and to invest microstructures, mechanical propertiesand fracture surfaces. The second is to prepare the diameter of3.0mm(Mg_0.65Zn_0.3Ca_0.05)_100-xM_x（M=Cu or Al, x=0,1,2,3,4） alloys rods by copper moldsuction casting method, and to invest the effects of Cu or Al on the corrosionresistances of Mg₆₅Zn₃Ca₅alloys.According to the eutectic point easy to form amorphous and Inoue’s threeprinciples, this thesis selected Mg-Zn-Ca eutectic point composition （E₁, E₂, E₄andE₅） as research objects. The compositions are Mg₇₂Zn₁₅Ca₁₃, Mg₆₂Zn₃₆Ca₂,Mg₁₄Zn₂₂Ca₆₄and Mg₂₆Zn₄₈Ca₂₆. The diameter of3.0mm Mg-Zn-Ca ternary eutecticalloys rods were prepared by copper mold suction casting method. Themicrostructures, mechanical properties and fracture surfaces were analyzed mainly byX-ray diffractometry（XRD）, optical microscope（OM）, micro-electric universal testingmachine and scanning electron microscopy（SE_M）. The results show that:Mg₇₂Zn₁₅Ca₁₃, Mg₁₄Zn₂₂Ca₆₄and Mg₂₆Zn₄₈Ca₂₆alloys formed composites ofamorphous and crystal phase, Mg₆₂Zn₃₆Ca₂alloy formed crystal. The strength andplastic strain of Mg₁₄Zn₂₂Ca₆₄is548MPa and0.9%. For the alloys, the fracturestrength was higher with lower crystallinity. The compressive fracture surfacesshowed that Mg₇₂Zn₁₅Ca₁₃, Mg₆₂Zn₃₆Ca₂, Mg₁₄Zn₂₂Ca₆₄and Mg₂₆Zn₄₈Ca₂₆were allbrittle fracture.The diameter of3.0mm (Mg_0.65Zn_0.3Ca_0.05)_100-xM_x（M=Cu or Al, x=0,1,2,3,4）alloys rods were prepared by copper mold suction casting method. The corrosionresistances, surface morphologies and element analysises were analyzed mainly byXRD, electrochemical workstations, scanning electron microscopy（SE_M）and energydisperse spectroscopy（EDS）. The results show that:（1） The Mg₆₅Zn₃Ca₅alloy formed amorphous alloy.(Mg_0.65Zn_0.3Ca_0.05)_100-xM_x（M=Cu or Al, x=1,2,3,4） alloys all formed composites of amorphous and crystalphase.（2） The results of electrochemical tests and surface morphologies of(Mg_0.65Zn_0.3Ca_0.05)_100-xM_x（M=Cu or Al, x=0,1,2,3,4） alloys in3%NaCl solution showed that: When x=2, that is the content of Cu or Al was2%, the corrosionresistances of (Mg_0.65Zn_0.3Ca_0.05)₉₈M₂（M=Cu or Al） alloys was best.（3） The results of quality loss corrosion,electrochemical tests and surfacemorphologies of (Mg_0.65Zn_0.3Ca_0.05)_100-xM_x（M=Cu or Al, x=0,1,2,3,4） in simulatedbody fluid（SBF） showed that: When x=4, that is when the content of Cu or Al was4%,the corrosion resistances of (Mg_0.65Zn_0.3Ca_0.05)₉₆M₄（M=Cu or Al） alloys was best.E_nergy spectrum analysis results showed that: When x=2, that is the content of Cu orAl was2%,(Mg_0.65Zn_0.3Ca_0.05)₉₈M₂（M=Cu or Al） alloy had good biocompatibility.