Numerical Simulation of Mechanical Property of Post Friction Stir Weld Artificial Ageing of Aluminum Alloy

• Main Authors: WAN Zhenyu, ZHOU Xia, ZHANG Zhao
• Format: Article
• Language: zho
• Published: Journal of Aeronautical Materials 2017-08-01
• Series: Journal of Aeronautical Materials
• Subjects: friction stir welding; precipitation; post weld heat treatment; artificial ageing
• Online Access: http://jam.biam.ac.cn/CN/Y2017/V37/I4/19

KWN model was used to establish the precipitation evolution model of friction stir welding of Al-Mg-Si alloy. The yield strength was divided into three parts:the contribution from grain size, the contribution from solid solution and the contribution from the precipitations. Based on this model, the yield strength and hardness of friction stir weld was predicted. The effect of post weld artificial ageing on mechanical properties of friction stir weld was further investigated. The results indicate that longer holding time can be beneficial to the recovery of mechanical properties in the stirring zone. Higher temperature can lead to quick recovery of mechanical properties in the stirring zone, but when the holding temperature is higher than 200℃, longer holding time can lead the base metal softened, which is harmful to the service of friction stir welds. The mechanical property in the heat affected zone cannot be improved by post weld artificial ageing.