1060铝板搅拌摩擦焊工艺参数与接头力学性能间的关系

The relationship between the process parameters of friction stir welding and mechanical properties of joint for 1060 aluminum plates

为研究3 mm厚1060铝板的搅拌摩擦焊工艺参数和接头力学性能之间的关系,使用经典函数关系式对焊接温度、晶粒大小和力学性能数据进行拟合。首先对厚度为3 mm的1060铝板进行搅拌摩擦焊试验,焊接过程中采用热电偶测量温度,然后利用显微镜分析接头组织形貌,最后对接头试样进行拉伸试验和硬度试验,并用扫描电镜分析断口特征。研究表明:焊接温度随搅拌头转速增大而提高,随焊接速度增大而降低,并且和搅拌头转速平方与焊接速度之比的0.168次方呈线性关系;焊接温度和焊核区的Zener-Hollomon数值的对数与焊核区晶粒大小的对数呈线性关系;焊核区晶粒大小与接头屈服强度符合Hall-Petch公式;硬度分布呈"W"形;断口主要呈韧性断裂。该研究结果可为搅拌摩擦焊生产工艺制定提供理论支撑。

In order to study the relationship between the process parameters of friction stir welding and mechanical properties of joints for 3 mm thick 1060 aluminum plates,classical function relations were used to fit the data of welding temperature,grain size and mechanical properties.Firstly,a friction stir welding test was carried out on a 3 mm thick 1060 aluminum plate,and the temperature was measured by a thermocouple during welding.Then,a microscope was used to analyze the microstructure of joints.Finally,a tensile test and a hardness test were conducted on the joint samples,and the fracture characteristics were analyzed by means of scanning electron microscopy.The results show that the welding temperature increases with the increase of rotating speed of friction stir tool,decreases with the increase of welding speed,and has a linear relationship with the ratio to the power of 0.168 of the square of rotating speed to the welding speed.The logarithm of the Zener-Hollomon value of the welding temperature and the weld nugget shows a linear relationship with the logarithm of the grain size.The grain size of the weld nugget and the yield strength of joints conform to Hall-Petch formula.The hardness distribution presents a"W"shape.The fracture is dominated by ductile fracture.The results provide a theoretical support for the design of the production process of friction stir welding.