This invention discloses a
nickel-
tantalum master
alloy, comprising, by
mass percentage: 40.0%–50.0%
nickel, with the balance being
tantalum and unavoidable impurities. The
nickel-
tantalum master
alloy is prepared from nickel foil, nickel
suboxide,
tantalum pentoxide, aluminum
powder, and
calcium granules. The specific preparation method is as follows: nickel
suboxide,
tantalum pentoxide, and aluminum
powder are mixed uniformly to obtain a mixture;
calcium granules are spread evenly at the bottom of a
crucible in a vacuum
aluminothermic reaction furnace, and a layer of
calcium oxide slurry is coated onto the inner wall of the
crucible. After
drying, the mixture is added to perform a vacuum aluminothermic / calcothermic reduction reaction to obtain a nickel-tantalum
alloy liquid. After cooling, a primary nickel-tantalum alloy is obtained;
tantalum pentoxide is wrapped in nickel foil to form multiple bales; the primary nickel-tantalum alloy is crushed, and the wrapped bales and crushed primary nickel-tantalum alloy are melted in a vacuum
electron beam furnace; the melted alloy liquid is cooled to obtain the nickel-tantalum master alloy. The nickel-tantalum master alloy obtained by this invention has high uniformity and high purity.