Experimental investigation of driver material on electromagnetic welding of alloy D9 SS tube to SS316L(N) plug

Abstract

In electromagnetic welding process, for a low electrically conductive outer tube material, physical and mechanical properties of conductive drivers are important to achieve strong wavy weld. However, the technology may not be cost-effective for joining such metals. This work investigates the effect of using driver materials (Al of thickness 0.65, 1.0, 1.3, and 2.0 mm and annealed Cu (up to 650°C) of thickness 0.5, 0.75, 1.0, and 1.5 mm) on effectively achieving welding between alloy D9 SS tube and SS316L(N) solid plug. Multiple experiments were conducted to determine the preferred material and thickness of the driver tube. The welded interface revealed a wavy morphology of 35–40 μm as maximum crest height and lowest helium leak rate of 4 × 10–10 m bar L/s with annealed Cu driver having thickness 1 mm. The experimental results prove that annealed Cu (up to 650°C) should be chosen over Al as driver material. The preferred driver thickness was found to be dependent on the frequency of the current pulse.