论文部分内容阅读
研究挤压和热处理对Mg-8Zn-1Al-0.5Cu-0.5Mn镁合金显微组织和力学性能的影响。结果表明,合金在230和260°C挤压时呈现双峰组织,而在290°C挤压时合金发生了完全的动态再结晶。随着挤压温度的升高,合金动态再结晶越充分,从而使其基面织构降低。通过研究4种不同的热处理制度对290°C下挤压成型合金的影响发现,经过固溶+时效处理后,合金的晶粒发生明显长大。与固溶+单级时效的合金相比,固溶+双级的工艺能显著细化析出相,提高析出相的密度。同时,经固溶+双级时效处理后合金的力学性显著提高,其屈服强度、抗拉强度和伸长率分别为298 MPa、348 MPa和18%,这主要是由细小的再结晶晶粒与均匀弥散分布的第二相共同作用的结果。
The effects of extrusion and heat treatment on the microstructure and mechanical properties of Mg-8Zn-1Al-0.5Cu-0.5Mn magnesium alloy were studied. The results show that the alloy exhibits bimodal structure when extruded at 230 and 260 ° C, whereas complete dynamic recrystallization of the alloy occurs at 290 ° C. With the increase of extrusion temperature, the dynamic recrystallization of the alloy is more fully and the texture of the base surface is reduced. Through the study of four different heat treatment system on the extrusion of 290 ° C alloy found that after solution treatment + aging, the alloy grain growth significantly. Compared with solid solution + single-stage aging alloy, the solid solution + two-stage process can significantly refine the precipitated phase and increase the density of the precipitated phase. At the same time, the mechanical properties of the alloy after solution treatment and two-stage aging were significantly improved. The yield strength, tensile strength and elongation of the alloys were 298 MPa, 348 MPa and 18%, respectively, which were mainly composed of fine recrystallized grains and The results of the synergistic effect of the second phase of uniformly dispersed distribution.