Magnetic Pulse Welding of the “Tube – Plug” Pair of STS410 Steel

The research was focused on the magnetic pulse welding (MPW) of 12.5% Cr steel STS410. The experiments were performed in the tube-plug geometry (both details were made of the same steel). Magnetic pulse unit consisted of pulsed current generator (PCG) loaded to a single-turn coil. Magnetic field amplitude of 40 T was generated in the coil during experiments. The amplitude of pulsed current reached 750 kA. The effects of energy storage capacity, charging voltage, and end plug shape were studied. The welded samples were investigated by optical microscopy. The optimal velocities of impact and contact front motion were evaluated as 300 m/s and 3-3.5 km/s, respectively. The paper includes the leakage test results as well. To date, the joints with a helium leak rate of 10 mbar·l·s have been produced.