Fractal Dimension Characterization of Joint Surface Morphology on Dissimilar Friction Stir Lap Welding of Al/Mg

Abstract

The joint surface of the 1060 aluminum and AZ31 magnesium alloy was prepared through friction stir lap welding (FSLW) under different welding process parameters. The joint surface was characterized three-dimensionally using a three-dimensional (3D) optical profiler, and the coordinate data were obtained. The fractal dimension of the joint surface was calculated by the box-width transformation method using a MATLAB program. Furthermore, the influence of the welding process parameters on the fractal dimension of the joint surface was studied. The response surface model was established based on the principle of central composite design (CCD), and analysis of variance (ANOVA) was carried out to test the accuracy of the response surface. The results showed that the joint surface morphology had fractal characteristics, and the fractal dimension could be used as an index to characterize the quality of the joint surface. The change of the welding process parameters had a great impact on the fractal dimension of the joint surface, the interaction between the parameters was small, and the fitting accuracy of the response surface model was high. The fractal dimension of the joint surface decreased with the increase in the welding and rotational speeds and the effect of the rotational speed was more significant.

Friction Stir Welding/Processing of Mg-Based Alloys: A Critical Review on Advancements and Challenges

“…However, in the butt joint design, two plates to be joined to each other are firstly fixed together by a fixture. Then, the rotary tool is plunged into the joint line and traverses along the joint line [2,27,28,89,90]. The highest temperature listed for the plate surface close to the tool path regarding the various tools was tested by using a ThermaCAM S40 infrared camera.…”

Analysis of micro-friction stir welding surfaces using fractal methodologies

“…Zuo et al [16] discussed the effect of process parameters (tool feed and tool rotational speed) on fractal dimension, and a good correlation between fractal dimension and average roughness (R a ) have been found. Zhao et al [17] performed a response surface methodology to study the effect of tool feed and tool rotational speed on the fractal dimension of FSW joint surfaces. It was concluded that the fractal dimension decreases with tool feed and tool rotational speed.…”

Effect of Al Content in Magnesium Alloy on Microstructure and Mechanical Properties of Laser-Welded Mg/Ti Dissimilar Joints

“…Nowadays, hybrid components of lightweight materials have been receiving extensive attention to achieve reduction of emissions and green development, which increases the demand for weight reduction in advanced manufacturing industry [1][2][3][4]. Magnesium (Mg), as one of the lightest engineering structural materials, has attracted wide attention due to its advantages of high strength, excellent formability and recyclability [5][6][7]. Titanium (Ti) has many features, such as high strength-to-weight ratio, good impact toughness and corrosion resistance [8,9].…”