STEFAN LUPESCU, CORNELIU MUNTEANU, BOGDAN ISTRATE, KAMEL EARAR THE INFLUENCE OF ZR ON MICROSTRUCTURE, MECHANICAL PROPERTIES AND CORROSION RESISTANCE IN MG-Y-ZR BIODEGRADABLE ALLOYS The latest magnesium alloys are widely used in the medical field, especially for biodegradable implants. Magnesium alloys are very attractive for applications in different structures in the automotive, aerospace, printing and even medical fields <1>. It should be noted that some magnesium alloys have excellent damping properties as well as good mechanical properties, making them promising to respond to high damping needs for vibration control <1,2>. Although widely used, magnesium has a low corrosion resistance. To improve this resistance, different types of magnesium based on aluminum, such as Ca, Mn, Zn, Zr, Si and rare rare (Y, Gd ..), can be developed. The main purpose of this paper is to investigate the properties of a primary alloy based on the Mg-1Y-0,5Zr system with different concentrations of Zr (0.5,1,2) used in the development of alloys based on the biodegradability of Mg. Surface morphology was characterized by electronic scanning microscopy (SEM), X-ray diffraction (XRD) and optical microscopy. After XRD analysis, it was observed that certain specific compounds were made up of Mg2Ca, MgZr, Mg2Y, Mg24Y5 having the main Mg formed in the hexagonal structure, but Mg24Y5 are the cubic crystalline structure. Also, the microhardness of the alloy is higher than pure Mg and the scratch mark is smaller than that of pure Mg. The corrosion resistance was developed using linear voltammetry in specific medium and corrosion showed that it had significantly decreased for masteralloy. As a final conclusion, the structural properties of this model are recommended for use as medical implants.
Keywords: Micro-Hardness, SEM, XRD, optical microstructure