2219铝合金厚板搅拌摩擦焊搅拌头结构参数优化

Optimization of tool structure parametersin friction stir welding thick 2219 aluminum alloy plate

为探究搅拌头几何形貌对2219铝合金厚板搅拌摩擦焊核心区温度场的影响,基于ABAQUS/CEL建立了18 mm厚2219铝合金FSW三维过程仿真模型,应用有限元分析法对焊接过程进行仿真研究,得到了焊接核心区测温点实时温度循环曲线。利用自主研发的热电偶测温系统对焊接温度场相应测温点温度进行检测,经过对比可知,不同转速试验和仿真数据曲线变化趋势基本相同,验证了所建立的FSW过程仿真模型的有效性。探究了搅拌头结构参数对FSW过程核心温度场的影响规律,针对搅拌头的轴肩尺寸、搅拌针锥角、轴肩凹角、螺纹升角等结构尺寸设计了4因素3水平正交试验。结果表明,轴肩直径对核心区温差的影响最为显著,当搅拌头的轴肩尺寸为36 mm、搅拌针锥角为6°、轴肩凹角为2.5°、螺纹升角为11°时,搅拌头结构尺寸较为合理,核心区温差值较小。

To investigate the impact of tool geometry on the temperature distribution in the core area of friction stir welding thick 2219 aluminum alloy plate,a three-dimensional simulation model of FSW 18 mm thick 2219 aluminum alloy is established based on ABAQUS/CEL.The finite element analysis method is applied to simulate the welding process and the real-time temperature cycle curve of the temperature measurement point in the core area of FSW is obtained.The temperature of the corresponding measurement points of the welding temperature field is detected by the developed thermocouple temperature measurement system,and the experimental and simulated data curves are basically the same at different rotation speeds,which verified the validity of the established simulation model.To explore the influence of the tool structure size on the core temperature field of the welding process,a four-factor,three-level orthogonal test is designed for the tool shoulder size,taper angle,shoulder concave angle,thread lift angle and other important details of the size.The results show that the shoulder diameter has the most significant effect on the temperature field difference of friction stir welding.When the shoulder size of the tool is 36 mm,the taper angle is 6°,the shoulder concave angle is 2.5°and the thread lift angle is 11°,the tool structure size is reasonable and the temperature field difference in the direction of the weld plate thickness is small.