新型Al-Zn-Mg-Cu合金型材双级时效组织性能研究  

Investigation on microstructure and properties of a new type Al-Zn-Mg-Cu alloy profile after duplex aging treatment

作　　者：王少华[1] 孟令刚[1] 房灿峰[1] 郝海[1] 张兴国[1] 

机构地区：[1]大连理工大学材料科学与工程学院,辽宁大连116024

出　　处：《材料研究与应用》2011年第3期190-193,共4页Materials Research and Application

基　　金：国家自然科学基金(50875031);华中科技大学材料成形与模具技术国家重点实验室开放课题(08-07)

摘　　要：通过拉伸性能测试及金相显微镜、扫描电镜和透射电镜分析,研究了一种新型Al-Zn-Mg-Cu合金挤压型材在120℃/4h+165℃/8h制度下的拉伸性能、电导率和显微组织等.结果显示:Al-Zn-Mg-Cu合金型材在此状态下的抗拉强度为548MPa,屈服强度为514.5MPa,延伸率为11.6%,电导率为41.7%IACS.相对于T73状态的7050合金型材,Al-Zn-Mg-Cu合金的抗拉强度提高了4.7%,屈服强度提高了11.6%,延伸率提高了12.6%,电导率相当.该合金的断裂方式为穿晶剪切断裂,主要沉淀相为η′相和η相.该合金型材具有优异的强韧综合性能.In this paper, the tensile properties, electrical conductivity and microstructure of a new type Al- Zn-Mg-Cu alloy profile after aging for 4h at 120℃ plus 8h at 165℃ were tested by tensile testingl optical microscopy （OM）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. The results show that the ultimate tensile strength, yield strength, elongation and electrical conductivity are548MPa, 514.5MPa, 11.6% and 41.7%IACS, respectively. Compared to 7050 alloy profile of T73 temper, the ultimate tensile strength, yield strength and elongation of the alloy increase by 4.7%, 11.6%, and 12.6%, while the electrical conductivity is equivalent. The fracture mode of the alloy is transgranular shearing fracture, and the major precipitates in the alloy are η′ and η phases under the aging condition. The alloy profile can obtain good strength and suitable toughness.

关 键 词：Al—Zn—Mg—Cu合金 型材 双级时效 显微组织 性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程]