搅拌摩擦焊接中搅拌头疲劳应力计算方法  

Computational Methods to Fatigue Stress of Stirring Head in Friction Stir Welding

作　　者：张昭[1,2] 吴奇[1,2] 

机构地区：[1]大连理工大学工程力学系,辽宁大连116024 [2]大连理工大学工业装备结构分析国家重点实验室,辽宁大连116024

出　　处：《机械研究与应用》2015年第6期29-33,共5页Mechanical Research & Application

基　　金：国家自然科学基金(编号:11172057;11572074);国家重点基础研究发展(973)计划(编号:2011CB013401);中央高校基本科研业务费专项资金;新世纪优秀人才支持计划(编号:NCET-12-0075)

摘　　要：采用计算流体动力学模型(CFD)模拟AA6061-T6搅拌摩擦焊接过程。基于得到的流场压力分布,计算出搅拌头受力。搅拌头受力分为轴肩下表面摩擦阻力、搅拌针阻力和搅拌针底部摩擦力,通过与试验结果的比较验证了方法的有效性。进一步提出计算搅拌针根部疲劳应力的解析方法,并与有限元数值解对比验证了其正确性。结果表明,搅拌头受力和搅拌针疲劳应力随焊接转速增大而减小,随焊速的增加而增加。但较大的转速,导致较高的疲劳应力交变频率。Computational fluid dynamic model is used to simulate the friction stir welding process. Based on the computed flu-id pressure, the forces on the welding tool can be obtained. The tool force consists of three components, the friction force on the shoulder contact region, the resistance force on the pin and the frictional force on the pin tip surface. The comparison to the experimental values can validate the proposed method. The fatigue stress on the tool pin can be then calculated by the pro-posed analytical method. The comparison of the analytical results and the finite element results can validate the proposed ana-lytical method. Results indicate that the fatigue stress can be increased with the increase of the transverse speed and can be decreased with the increase of the rotating speed. But higher rotating speed can lead to higher frequency of the alternative stress.

关 键 词：搅拌摩擦焊接 CFD模型 疲劳应力 

分 类 号：TG402[金属学及工艺—焊接]