ELECTROSLAG REMELTING OF COBALT-BASE SUPERALLOYS.

A study was undertaken to determine the feasibility and possible advantages of electroslag remelting three cobalt-base superalloys - i. e. , MAR-M 302, MAR-M 509, and X-45 - selected to cover as wide a composition range as possible. The alloys were successfully electroslag remelted in an inert gas using single-phase a. c. power and CaF//2-CaO-Al//2O//3 or CaF//2-CaO-MgO-Al//2O//3 fluxes. Vacuum-arc remelts were prepared for comparison purposes. Stress-rupture data indicated a slight superiority of electroslag remelted over vacuum-arc remelted material at all temperatures for MAR-M 302, and at medium temperatures for MAR-M 509 and X-45.