Affiliation:
1. Suzhou Nonferrous Metal Research Institute, LTD
2. Chongqing Jiaotong University
Abstract
In this study, the effect of Mg/Si ratio, Cu content and/or pre-ageing treatment (e.g. 100 °C for 2 h and/or 200 °C for 20 s) on the stretch formability of 6xxx alloys was investigated through their influence on the work hardening and strain-rate hardening behaviour using tensile testing and forming limit diagram tests. The results showed that a high Mg/Si ratio, a low Cu content and/or the employment of pre-ageing could deteriorate the stretch formability due to the decrease in work hardening and/or strain rate hardening capabilities. Moreover, the stretch formability was observed to have an opposite correlation with the paint-bake response of the alloys studied.
Publisher
Trans Tech Publications, Ltd.
Subject
Mechanical Engineering,Mechanics of Materials,Condensed Matter Physics,General Materials Science
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