Vacuum melting method for alloy with high return ratio

Abstract

The invention provides a vacuum melting method of a high return ratio alloy, the vacuum melting raw materials of the high return ratio alloy comprise Ni-9996, Ni-9999, M-Cr, M-Mo, M-Al, M-Ti, M-Nb, M-Ce, M-Mn, a carbon electrode and a reclaimed material, the vacuum melting method of the high return ratio alloy comprises the following steps: cleaning the raw materials; melting the raw materials; a vacuum refining process; alloying the raw materials; a pouring forming process; cooling and shaping; according to the technical scheme, only part of the niobium element is added in the later stage of refining, the high yield of the niobium element is ensured, and segregation of the niobium element is avoided; meanwhile, the melting period is changed from less than 30Pa to less than 10Pa to melt the scraps, and the melting operation under high vacuum degree is beneficial to removing the N element; c and other materials are separately added in the center of the prior art of the first part, C and Al are added at the same time in the scheme, the local exothermic reaction occurs, the local temperature is made to be 1800 DEG C or above due to the addition of Al, the carbon-oxygen reaction is promoted, [C] + [O] = CO, and the element O is greatly reduced and removed.

Description

technical field [0001] The invention relates to the technical field of alloy smelting, in particular to a vacuum smelting method for alloys with a high return ratio. Background technique [0002] GH3039 is a solid solution strengthened single-phase nickel-based austenitic superalloy. The main function of alloying elements is to contain Ni to form a face-centered cubic austenite matrix, improve oxidation resistance, corrosion resistance and element diffusion capacity; Cr, W, Mo play a role in solid solution strengthening and are also carbide forming elements; Al, Ti and Nb are γ' phase [Ni3(Al, Ti)] intermetallic compound strengthening elements, which are dispersed in the matrix and affect the dislocation behavior to strengthen the alloy. The superalloy GH3039 has high strength and durability at the working temperature of 800 ℃ ~ 900 ℃, good oxidation resistance, good plasticity at room temperature, and easy to form. It is especially suitable for manufacturing working parts...

AI Technical Summary

Problems solved by technology

[0004] 1. Using brand-new metal raw materials for vacuum induction steelmaking, since the total content of chromium and niobium elements that are easy to form nitrides is 20.8-23.3%, and the content of raw material full-melting smelting gases is generally O>30ppm, N>70ppm. Neither shape nor malleability benefits

[0005] 2. Niobium is prone to segregation due to the influence of the amount and time of addition in the steelmaking process. Using new metal raw materials for vacuum induction steelmaking, the amount of niobium added in the later stage of refining is too large, which is not conducive to the electrode’s effect on niobium. Harvest and control of its segregation