A tungsten submerged arc welding process wherein a non-consumable electrode (18) provides an arc (16) under a protective bed of flux powder (26), thereby eliminating the need for an inert cover gas supply. The arc melts a feed material in the form of alloy powder (22) or filler wire (40) along with a surface of a substrate (12) to form a layer of cladding material (10, 32) covered by a layer of slag (20, 44). The flux and slag function to shape the deposit, to control cooling, to scavenge contaminants and to shield the deposit from reaction with air, thereby facilitating the deposit of previously unweldable superalloy materials.