Study Of Corrosion Behavior Of Mg-Zn-Ca Therr-olimensional Magnesium Alloy Material In Hank’s Simulation Body Fluids

Magnesium alloys is similar with human bone mineral density and match with human bone elastic modulus, and many other excellent mechanical properties, and is considered a potentially biodegradable biomedical materials.Mg, Zn and Ca are necessary and trace elements for human body. They can promote human bone growth, adjust the muscle and neural activity. So Mg-Zn-Ca alloys get more and more attention at home and abroad as medical biodegradable material and human implant material. Magnesium alloys will have a broad application prospect in biological corrosion biodegradable materials field.This experiment take Mg as solvent, Zn and Ca as solutet. Three kinds of degradable ternary Mg-0.5Zn-xCa alloys with Ca contents of0.25%,0.5% and1%, and three kinds of degradable ternary Mg-xZn-0.25Ca alloys with Zn contents of0.5%,1% and2%respectively, were fabricated by the protection of the flux method. Do corrosion experiment at constant temperature37℃, taking the refining of magnesium alloys for corrosion materials and simulated body fluid as aggressive medium. Corrosion time from0to32days. Study the influence that different content of Ca and different content of Zn to Mg-Zn-Ca alloy organization and corrosion resistance, using Macro corrosion observed, SEM morphology observation, EDS analysis, XRD analysis, determination of the corrosion rate and electrochemical analysis methodThe results show that Mg-0.5Zn-xCa alloys and Mg-xZn-0.25Ca alloys grain were refining with more Ca and more Zn added. Mg-0.5Zn-xCa alloys composition include a interstitial, MgZn and Mg2Ca; Mg-xZn-0.25Ca alloys composition include a interstitial, MgZn, Mg2Ca and MgZn2.The corrosion rate of corrosion test indicated that Mg-0.5Zn-1Ca alloys corrosion is the most serious and Mg-xZn-0.25Ca (x=0.5、1、2)alloys corrosion get aggravated with more Zn added. Electrochemical results show, Mg-0.5Zn-0.25Ca alloy Ecorr and polarization resistance is the highestin Mg-0.5Zn-xCa(x=0.25、0.5、1) alloys. So Mg-0.5Zn-0.25Ca alloy shows an enhanced corrosion resistance. Mg-0.5Zn-0.25Ca alloy Ecorr and impedance is the highestin Mg-xZn-0.25Ca(x=0.5、1、2) alloys, so Mg-0.5Zn-0.25Ca alloy shows an enhanced corrosion resistance.