【摘要】 制备了3种不同成分的Mg-Gd-Y三元合金,并对其显微组织和力学性能进行了研究。结果表明,Mg-6Gd-(2-4)Y三元合金的铸态组织由α-Mg和呈现典型的网状共晶形貌的Mg24(GdY)5相组成,其体积分数随Y含量的增加而增大。热挤压过程中Mg24(GdY)5相破碎,呈颗粒状沿挤压方向排列。挤压态合金在高温固溶处理后,大部分Mg24(GdY)5相溶入基体。挤压态合金在固溶+时效(T6)处理和直接时效(T5)处理过程中都形成了β’沉淀。3种合金中Mg-6Gd-4Y合金在T5态的性能最好,强度高达350 MPa。更多还原

【Abstract】 Three ternary alloys with composition of Mg-6Gd-(2-4)Y(mass fraction,%) were prepared and their microstructure and mechanical properties were investigated.The results show that the as cast microstructure of the three alloys consist of α-Mg matrix and Mg24(GdY)5 eutectic phase.With increase of Y content the volume fraction of the Mg24(GdY)5 eutectic increases.After extrusion the Mg24(GdY)5 eutectic networks are destroyed and its broken particles are arranged in strips along the direction of extrusion.Solid solution treatment at high temperature above 520 ℃ resulted in the dissolution of Mg24(GdY)5 phase into the matrix.Both T6 treatment and T5 treatment caused the formation of β’ precipitates.High tensile strength combined is obtained from the Mg-6Gd-4Y alloy after T5-aging.更多还原