The invention discloses a Y-doped Mg
alloy. The Y-doped Mg
alloy is composed of Mg, Zn, Zr and Y and comprises, by
mass, 4.9-5.5% of Zn, 0.16-0.19% of Zr, 2.9-3.2% of Y, and the balance Mg and inevitable impurities. A preparation method of the Y-doped Mg
alloy comprises the steps of (1) preparation of alloy
powder, specifically, adding ethyl
alcohol to Mg-Zn-Zr
powder and Y
powder, adding
zinc stearate, conducting
vacuum pumping, and conducting ball milling to obtain the alloy powder; (2)
sintering, specifically, feeding the alloy powder into a vacuum
hot pressing sintering furnace, and conducting
vacuum pumping, heating
sintering and cooling to obtain an alloy billet; and (3) hot
extrusion, specifically, conducting heat preservation, feeding the alloy billet into an
extrusion die for
extrusion and then obtaining the Y-doped Mg alloy. According to the Y-doped Mg alloy and the preparation method thereof, the
rare earth element Y is subjected to
solid solution to go into a Mg base body to promote formation of an alloy double-peak
crystal structure, grain refinement, generation of high-melting-point hard phases and the like. On the premise of ensuring the strength, the
toughness and plastic
formability of the Mg alloy are improved, and a certain reference basis is provided for actual application of the Y-doped Mg alloy.