Abstract: The method consists in that a flat work in an initial position is oriented horizontally between cooled mold beams. Plasma torches are arranged in line across the parallel side edges so that the anode spots of the extreme torches are confined by said edges of the work. By supplying a plasma forming gas and electric current to the plasma torches the work is heated with the formation of a metal pool which extends across the work from edge to edge. By relatively moving the work and the plasma torches in a horizontal plane and along the edges of the work movement of the metal pool over the surface thereof is effected and thereby a remelted layer as thick as the pool is deep, is obtained. The apparatus for carrying out the method comprises a sealed chamber containing a mold having two beams arranged in a horizontal plane and being parallel to one another.

Abstract: In a plasma-arc torch for melting metals the electrode assembly comprises an electrode holder made of copper alloys and having a butt portion which rigidly secures a tungsten electrode by means of diffusion welding. The invention provides for a welded joint between the electrode and the electrode holder, a nonconsumable current-conducting interlayer made of titanium, copper and tungsten being placed therebetween.