... gear shafts, heat treatment of steel bars Main feature 1.light weight, small size and simple structure2.simple to operate, ... :1, diamond tools, carbide cutting tools welding.2, metal steel - steel, steel - copper, copper - copper equivalent metal or dissimilar metals in ... -frequency welding.3, metal quenching, annealing, quenching, tempering and heat treatment.4, metal forging, hot forming.5, powder ...