LA141镁锂合金搅拌摩擦焊接过程温度场模拟

Simulation of temperature field during friction stir welding of LA141 Mg-Li alloy

本文以厚度为2 mm的LA141镁锂合金板材为焊接材料,并利用ANSYS有限元软件,建立了搅拌摩擦焊温度场的有限元模型,利用APDL进行ANSYS软件二次开发,编写了热源移动程序,模拟了搅拌摩擦对焊的温度场分布规律.分析了转速、焊速、转速与焊速比对温度场的影响,获得了合理的LA141搅拌摩擦焊接工艺参数.模拟结果表明,温度场峰值温度与焊接转速成正比,焊接过程热量输入与焊速呈负相关,但不是线性关系.转速与焊速比值反映着热量输入状况,由于转速和焊速对热输入和热传递影响不同,所以在相同的转速与焊速比下,焊接过程温度场分布状况不同.高转速和焊速时,峰值温度高,热影响范围窄.

In this work,the LA141 Mg-Li alloy with the thickness of 2 mm was used to simulated the temperature field distribution during friction stir welding process.The finite element model of the temperature field of friction stir welding was established by ANSYS finite element software.In the process of establishing the finite element,the heat source movement program was programmed by APDL.The influence of rotational speed,welding speed,rotational speed and welding speed ratio on the temperature field was studied,and the reasonable welding parameters were discussed.The simulation results show that the peak temperature of the temperature field is directly proportional to the welding speed.The heat input in the welding process is inversely related to the welding speed,but they are not the linear relation..The rotational speed and welding speed ratio reflect the heat input.Because the rotational speed and welding speed have different effects on heat input and heat transfer,the temperature field distribution is different even if the same rotational speed and welding speed ratio.At higher rotational speed and welding speed,it has the higher peak temperature and narrower the range of heat influence.