相对挤压比对Al-Zn-Mg合金构件不同部位组织和性能的影响

doi:10.13251/j.issn.0254-6051.2021.03.004

摘要/Abstract

摘要： 采用全谱直读光谱仪、X射线衍射技术、拉伸试验测试方法和光学显微镜、扫描电镜、透射电镜、能谱仪观察方法,研究了相对挤压比对Al-Zn-Mg合金构件不同部位热处理前后微观组织和性能的影响。结果表明:挤压态和时效态构件中都存在Al₃(Zr,Ti)粒子。相对挤压比越大,Al₃(Zr,Ti)粒子含量越高,对热处理过程中再结晶抑制程度越强,热处理后构件仍保留大量的纤维组织,且MgZn₂相会在晶界处析出聚集;相对挤压比越大,热处理后构件平均晶粒尺寸增幅越低,屈服强度、抗拉强度和伸长率提升越大。

关键词: Al-Zn-Mg合金, 相对挤压比, 热处理, Al₃(Zr,Ti)粒子, MgZn₂相, 微观组织, 力学性能

Abstract: Effect of relative extrusion ratio on the microstructure and properties of different positions in Al-Zn-Mg alloy component before and after heat treatment was investigated by using inductive coupled plasma (ICP), X-ray diffractometry (XRD), tensile tests and microstructure observation by optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy disperse spectroscopy (EDS). The results show that Al₃(Zr,Ti) particles exist in both the as-extruded and aged microstructure. The larger the relative extrusion ratio and the higher the content of Al₃(Zr,Ti) particle is, the stronger the degree of recrystallization inhibition during heat treatment is, and large amount of fibrous tissue microstructure remains in the structure after heat treatment as well as the MgZn₂ phase precipitates and aggregates at the grain boundaries. The larger the relative extrusion ratio is, the smaller the average grain size increment after heat treatment is, and the larger the increments of yield strength, tensile strength and elongation are.

Key words: Al-Zn-Mg alloy, relative extrusion ratio, heat treatment, Al₃(Zr,Ti) particles, MgZn₂ phase, microstructure, mechanical properties

中图分类号:

TG146.2

黄元春, 章强, 聂昌昌, 谭维杨. 相对挤压比对Al-Zn-Mg合金构件不同部位组织和性能的影响[J]. 金属热处理, 2021, 46(3): 17-23.

Huang Yuanchun, Zhang Qiang, Nie Changchang, Tan Weiyang. Effect of relative extrusion ratio on microstructure and properties of different parts in Al-Zn-Mg alloy component[J]. Heat Treatment of Metals, 2021, 46(3): 17-23.

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