Mg-Zr系合金の合金元素について(第1報)

抄録

Grain refining effect of Zr on magnesium is caused by Zr which solves into molten magnesium alloy. A study was made on solubility of Zr in molten magnesium alloy and effect of Zr on cast structure of such alloy, when one of such metals as Ag, Al, Be, Bi, Ca, Cd, Ce, Cu, Fe, Li, misch metal, Mn, Pb, Si, Sn, Th, Ti and Zn is contained in magnesium as an alloying element.
The solubility of Zr at the temperature of 700°C is; 0.5-0.6% in Mg-Ag-Zr, similar to Mg-Zr binary alloy in Mg-Be-Zr, about 0.45% in Mg-Bi-Zr, 0.5% in Mg-Ca-Zr, 0.55-0.6% in MgCd-Zr, 0.5-0.55% in Mg-Ce-Zr, 0.4-0.5% in Mg-Cu-Zr, 0.35-0.5% in Mg-Li-Zr, 0.55-0.6% in Mg-Misch metal-Zr, 0.4-0.5% in Mg-Pb-Zr, more than Mg-Zr benary alloy in Mg-Th-Zr, 0.45% in Mg-Ti-Zr, 0.75-0.8% in Mg-Zn-Zr and considerably dicreases in Mg-Sn-Zr as Sn increases. Solubility of Zr in magnesium is remarkably prevented by Al, Fe, Mn and Si contained. Solubility of Zr in Mg-Zn-Zr containing Al, Fe, Mn and Si is not so decreased as in the case of Zn being not contained.
The grain refining effect of Zr on the cast structure is dependent on the quality of Zr which is to be solved in molten alloys.