锌镁元素含量对新型Al-Mg-Zn合金组织和力学性能的影响  

Effect of Zn and Mg Element Content on Microstructure and Mechanical Properties of New Type Al-Mg-Zn Aluminum Alloys

作　　者：欧世声 邓运来[1,2] 刘胜胆[1,2] 戴青松[1] 

机构地区：[1]中南大学材料科学与工程学院,湖南长沙410083 [2]中南大学有色金属材料科学与工程教育部重点实验室,湖南长沙410083

出　　处：《热加工工艺》2017年第24期135-139,共5页Hot Working Technology

基　　金：国家"973"重点基础研究发展计划项目(2012CB619500);国家自然科学基金项目(51375503)

摘　　要：采用硬度实验、室温拉伸实验、扫描电镜和透射电镜研究了锌镁含量对Al-6Mg-3Zn、Al-6Mg-4Zn和Al-7Mg-4Zn合金时效硬化行为、力学性能和显微组织的影响。结果显示:Al-Mg-Zn合金水冷淬火后进行人工时效时会产生时效硬化效果,其中人工时效硬化效果最好的是Al-7Mg-4Zn,峰值时效后板材硬度达182 HV3,屈服强度达529MPa,抗拉强度为580 MPa,伸长率为10.5%。3种合金经120℃×24 h时效后沉淀强化相为η'相,锌镁元素含量的增加,降低了合金的时效态组织再结晶分数,同时使得沉淀强化相的尺寸减小、弥散程度增加,最终使合金具有较高的强度。The effects of Zn and Mg content on the aging hardening behavior, mechanical properties and microstructure of Al-6Mg-3Zn, Al-6Mg-4Zn and Al-7Mg-4Zn alloys were investigated by hardness testing, tensile test at room temperature, scaning electron microscope and transmission electron microscope. The results show that Al-Mg-Zn alloys after water quenching and then artifical aging generate aging hardening effects. Al-7Mg-4Zn alloy exhibits the best artifical aging hardening effect. The hardness, yield strength and tensile strength of Al-7Mg-4Zn alloy sheet after peak aging are 182 HV3, 529 MPa and 580 MPa, respectively. The elongation of the aged sheet is about 10.5%. After aging treatment at 120 ℃ for 24 h, the precipitated phases of three kinds of Al-Mg-Zn alloys are η＇ phases. The increase of Zn and Mg element content results in the decrease of recrystallization volume percent of the alloys in aging states and making the size of precipitation strengthening phase decrease and dispersion degree increase, and then, the alloys have higher strength.

关 键 词：Al-Mg-Zn铝合金 锌镁含量 时效硬化行为 力学性能 

分 类 号：TG156.9[金属学及工艺—热处理]