【摘要】 制备了Mg-6Al-1.0Ca-0.5Mn-x Sm（x=0.5,1.5,4.5,质量分数,%）合金,研究了合金的显微组织和力学性能。实验结果表明,随着Sm质量分数的增加,Al₂Sm相主要在晶内析出且体积分数增加,相反Mg₁₇Al₁₂相的体积分数降低;挤压后合金发生动态再结晶,晶粒细化。在室温条件下,含1.5%Sm合金显示了最佳的力学性能,其极限抗拉强度、屈服强度和伸长率分别为316 MPa,148 MPa和21.3%。该合金优异的力学性能主要是由于晶粒细化、Al₂Sm颗粒的弥散强化和减少Mg₁₇Al₁₂相的析出。更多还原

【Abstract】 The effect of Sm addition（0.5, 1.5, 4.5, wt%） on microstructure and mechanical properties of extruded Mg-6Al-1.0Ca-0.5Mn alloys was investigated. Results show that with increasing the Sm content, the Al₂Sm phase precipitates in the matrix and the volume fraction of the phase increases but that of Mg₁₇Al₁₂ phase decreases. The grains of alloys are refined due to the sufficient dynamic recrystallization during the extrusion process. The alloy containing 1.5 wt% Sm exhibits the best mechanical properties, whose UTS, yield strength and elongation are 316 MPa, 148 MPa and 21.3%, respectively. The improved mechanical properties are mainly attributed to grain refinement, the precipitation strengthening of Al₂Sm particles and less Mg₁₇Al₁₂ phase in the matrix.更多还原