7055铝合金二次时效特征研究——(I)力学性能  

Investigation of Secondary Ageing Characteristics of 7055 Aluminum Alloy—I. Mechanical Properties

作　　者：李海[1] 郑子樵[1] 王芝秀[1] 

机构地区：[1]中南大学,湖南长沙410083

出　　处：《稀有金属材料与工程》2005年第7期1029-1032,共4页Rare Metal Materials and Engineering

基　　金：国家'973'重点基础研究项目(G1999064900-9)

摘　　要：利用维氏硬度和拉伸力学性能测试、Kahn撕裂试验等方法,研究二次时效对7055铝合金力学性能的影响。结果表明,经过120℃,150℃和180℃高温欠时效,甚至峰值时效处理后,再进行60℃和100℃低温二次时效,可以获得超过相应单级峰值时效的硬度和强度。Kahn撕裂试验表明,二次时效温度从60℃提高到100℃,可以缩短二次峰值硬化时间,但不利于7055铝合金断裂韧性的改善。在相同预时效温度下,缩短预时效时间比峰值时效状态更有利于断裂韧性的改善。较低预时效和二次时效温度以及较短预时效时间有利于获得强度和断裂韧性的良好配合。The influence of secondary ageing on the mechanical properties of 7055 Al alloy was investigated on the basis of Vickers hardness measurement, tensile test and Kahn tear test. The results showed that low temperature secondary ageing could increase microhardness and strength of 7055 Al alloy after preliminary ageing at 120℃, 150℃ and 180℃. Increasing of the secondary ageing temperature from 60℃ to 100℃ could accelerate the response of secondary hardening and strengthening, but deteriorate fracture toughness of 7055 Al alloy. Reducing of the preliminary temperature and the time was more favorable to the improvement in strength and toughness of 7055 Al alloy.

关 键 词：7055铝合金 二次时效 Kahn撕裂试验 力学性能 

分 类 号：TG113.25[金属学及工艺—物理冶金]