Study on Effects of Pulsed Current Treatment on Ultrasonic Welded Joint of Al5052‐H32 Alloy

The effect of pulse current on the mechanical properties of ultrasonic welded joints of 5052‐H32 aluminum alloy (Al5052‐H32) plate with a thickness of 2 mm is investigated experimentally. First, ultrasonic lap welding is performed to prepare the welded joint. Then, the pulsed current with different current densities and durations is applied to the welded joint. The impact of pulsed current on the properties of the welded joints is evaluated through tensile lap shear testing, observation using a metallographic microscope, and hardness testing. In the results, it is indicated that the tensile lap shear strength, elongation, and hardness of the welded joints can be improved by applying pulsed current properly. However, excessive input of electrical energy can lead to a decrease in the mechanical properties of the welded joints. Compared to the joint without pulse current treatment, the microstructure shows significant healing of the weld seam under the action of pulsed current. The feasibility of enhancing the mechanical performance of ultrasonically welded joints through the utilization of pulsed current is highlighted by these findings.