摘要
The as-extruded Mg-10Al_(2)Y master alloy was chosen as a novel grain refiner for as-cast Mg-3Y alloy.Contrast samples of cast Mg-3Y alloy added with pure Al and Mg-Zr master alloy grain refiners were prepared under the same conditions.In this study,the influence of addition amounts of Al_(2)Y and holding time on grain refinement efficiency as well as tensile properties was investigated.And the grain refining ability of the Al_(2)Y particles was systematically evaluated in terms of the addition amounts,number density of the Al_(2)Y particles and holding time.The finest grains are achieved at 2 wt% Al_(2)Y addition amount,which corresponds to number density of the polygonal Al_(2)Y particles of 420-460 mm^(-2).The Mg-10Al_(2)Y master alloy has significant refinement performance and no refining recession occurs at the holding time within 60 min,or the settling time up to 180 min.Grain refinement and the second phase strengthening of uniformly distributed Al_(2)Y particles contribute to the simultaneous enhancement on both strength and elongation of Mg-3Y alloy.
基金
Project supported by the Chongqing Science and Technology Commission(cstc2017zdcy-zdzxX0006,cstc2018jcyjAX0472,cstc2018jcyjAX0339)
Science and Technology Research Program of Chongqing Municipal Education Commission(KJQN201801306,KJ1711290)
Chongqing University of Arts and Sciences(501100002867)(P2017XC08)。
