Development of a Technology for Producing a Rhenium–Nickel Master Alloy for Alloying of Cast Nickel Superalloys

Abstract—A technology for producing a rhenium–nickel alloy for alloying cast nickel superalloys is presented. The optimum technological scheme for manufacturing a master alloy from preparing a raw material to the final product is developed. The feasibility of vacuum annealing of a rhenium powder before melting, which ensures both sintering and degassing of the powder, is justified. Technological conditions for annealing of the powder and melting of the master alloy in a vacuum arc furnace with a nonconsumable electrode are developed to minimize the gas ([O], [N]) content, to ensure a high yield (η = 99.9–100%), and to achieve a uniform distribution of the main components over the ingot volume. The master alloy has been successfully tested in the production of single-crystal nickel superalloys.