MAGNESIUM ALLOY, METHOD OF ITS MANUFACTURE AND USE

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FIELD : metallurgy. SUBSTANCE : biodegradable implant contains magnesium alloy comprising : Zn in amount from 3 to 5 wt %, Ca in amount from 0.2 to 0.4 wt %, the rest is represented by magnesium containing impurities facilitating electrochemical differences of potential and/or formation of intermetallic phases, in total amount not exceeding 0.0048 wt %. The total amount of impurities contains : separate impurities from the group of Fe, Si, Mn, Co, Ni, Cu, Al, Zr, and P in amount not exceeding 0.0038 wt %. The Zr content is less than 0.0003 wt %, and alloying elements selected from the group of rare earth elements having atomic numbers 21, 39, from 57 to 71 and from 89 to 103, in amount not exceeding 0.001 wt %. The alloy contains the intermetallic phase of Ca2Mg6Zn3 and, optionally, isolated phase of MgZn, each of which is characterized by volume content close to up to 2%, dispersed at grain boundaries with size <5 mcm. EFFECT : biodegradable implant is in stable electrochemical condition with low porosity and high corrosion resistance over a long period of time due to high values of ultimate strength and yield point, and reduced value of mechanical asymmetry. 30 cl, 1 ex