Reducing pores during electron - beam welding - by adding aluminium to the weld bead before or during welding

摘要

The amount of pores produced during electron-beam welding due to the evolution of Co and N from the bead is reduced prior to or during welding by adding Al either as vapour coating or as foil to the weld bead. For a steel contg. is approx. 1% C, 17 ppm O and 90 ppm N, enough Al is added to ensure a calculated Al content 0.3%.