The Effect of Welding Current and Electrode Force on the Heat Input, Weld Diameter, and Physical and Mechanical Properties of SS316L/Ti6Al4V Dissimilar Resistance Spot Welding with Aluminum Interlayer

Abstract

Welding parameters obviously determine the joint quality during the resistance spot welding process. This study aimed to investigate the effect of welding current and electrode force on the heat input and the physical and mechanical properties of a SS316L and Ti6Al4V joint with an aluminum interlayer. The weld current values used in this study were 11, 12, and 13 kA, while the electrode force values were 3, 4, and 5 kN. Welding time and holding time remained constant at 30 cycles. The study revealed that, as the welding current and electrode force increased, the generated heat input increased significantly. The highest tensile-shear load was recorded at 8.71 kN using 11 kA of weld current and 3 kN of electrode force. The physical properties examined the formation of a brittle fracture and several weld defects on the high current welded joint. The increase in weld current also increased the weld diameter. The microstructure analysis revealed no phase transformation on the SS316L interface; instead, the significant grain growth occurred. The phase transformation has occurred on the Ti6Al4V interface. The intermetallic compound layer was also investigated in detail using the EDX (Energy Dispersive X-Ray) and XRD (X-Ray Diffraction) analyses. It was also found that both stainless steel and titanium alloy have their own fusion zone, which is indicated by the highest microhardness value.

Magneto-Optical Imaging of Arbitrarily Distributed Defects in Welds under Combined Magnetic Field

“…The permeability change curve of the ferromagnetic sample under the CMF is named conventional permeability. Therefore, the expression of permeability can be expressed by Equation (10). Equation ( 11) is obtained by differentiating the two sides of Equation (10).…”

“…Therefore, the expression of permeability can be expressed by Equation (10). Equation ( 11) is obtained by differentiating the two sides of Equation (10). Then, according to the relationship between total differential and partial differential equation, the partial differential equation can be obtained by sorting out Equation (11), as shown in Equation (12).…”

“…Spot welding is used to weld individual points on the contact surface of the weldment at the joint. In industrial production, spot welding is mainly used in the following aspects: (1) overlap in sheet metal stamping parts, (2) thin plate and section steel structures and skin structures, (3) screens, space frames, and cross steel bars, and so on [10,11]. In order to ensure the quality of products and projects, while avoiding accidents, non-destructive inspection of welds is required [12].…”

Phase Formation during Heating of Amorphous Nickel-Based BNi-3 for Joining of Dissimilar Cobalt-Based Superalloys

“…Also, depletion of chromium in adjacent zones through the consumption of secondary phase precipitations reduces corrosion resistance, particularly at high temperatures. Consuming alloying elements of base metals in area adjacent to the bonding zone reduces the alloying elements, leading to reinforcement with a solid solution and carbide deposition (such as tungsten, molybdenum, and chromium) [44][45][46][47][48][49][50][51][52][53][54][55][56][57][58]. Consequently, it is essential to apply post-bond heat treatment to remove secondary phase compounds in the diffusion-affected zones.…”

Case Study About Resistance Projection Welding of Aluminized Steel Parts

“…Reported studies have shown that if the welding current increases from 4 to 11 kA and the welding time increases from 50 to 300 ms, the diameter of the welded nugget increases [12], causing the coarse grains formation and cracks at the interface of the joint [15]. In these situations, weaker adhesion values and cracks in the weld were reported, by weakening the grain boundaries due to intermetallic compounds (Fe 2 Al 5 and Fe 4 Al 13 phases) formation [15] - [18].…”