Alloy for refining nickel-based superalloy and method of use thereof

Abstract

The invention relates to a nickel-based high-temperature alloy, in particular to an alloy for nickel-based high-temperature alloy refining and a using method thereof. The alloy for refining consists of the following components in percentage by mass: 11 to 20 percent of Al, 71 to 80 percent of Ba, and 4 to 10 percent of Sr. The refining alloy is used for substituting the traditional Ca for refining; compared with single Ca or Ca alloy, the barium-based alloy has low melting point and high boiling point, so the yield is high; the Ba and the Sr have stronger refining desulfuration and dephosphorization capacities compared with the Ca or Ca alloy, the alloy has stronger capacities of refining and removing P, S and O; and in addition, the Sr also has the effect of purifying aluminum deoxidation products and denatured inclusions. The alloy has the advantages that: sulfur and phosphorus in the nickel-based alloy can be reduced to below 0.006 percent, and the performance of the nickel-based high-temperature alloy is remarkably improved; and the process is simple, mature in conventional process equipment, low in cost and worthy of popularization.

Description

technical field [0001] The invention relates to a nickel-based high-temperature alloy, in particular to an alloy for refining a nickel-based high-temperature alloy and a use method thereof. Background technique [0002] Nickel-based superalloys are currently important superalloy materials used in high-end applications such as aerospace, nuclear power, and military equipment. Compared with iron-based superalloys, nickel-based superalloys have better high-temperature resistance; nickel-based superalloys still need There is a relatively high content of easy-to-oxidize alloying elements such as Cr, Mo, Co, Ti and other strengthening elements. These easy-to-oxidize element alloys and nickel metal itself become an important source of harmful impurity elements in the alloy, especially S and P. In nickel-based superalloys The content of harmful impurity elements S and P is required to be less than 0.010-0.020%; the current means of controlling S and P harmful elements in nickel-base...

AI Technical Summary

Problems solved by technology

[0002]Nickel-based superalloys are currently important superalloy materials used in aerospace, nuclear power, ordnance and other high-end applications. Compared with iron-based superalloys, nickel-based high-temperature The high temperature resistance of the alloy is more excellent; nickel-based superalloys still need to have a high content of easy-to-oxidize alloying elements such as Cr, Mo, Co, Ti and other strengthening elements, and these easy-to-oxidize element alloys and nickel metal itself become harmful impurities in the alloy An important source of elements, especially S and P. The content of harmful impurity elements S and P in nickel-based superalloys is required to be less than 0.010-0.020%. At present, the means of controlling the harmful elements of S and P in nickel-based superalloys include: 1) Strict control Harmful elements of S and P in raw materials, that is, to improve the purity of raw materials, which will greatly increase the cost; 2) through vacuum induction melting and vacuum electroslag remelting process, vacuum induction melting is treated with Ca to reduce S in the alloy And P, through vacuum electroslag remelting, the S content is further reduced, but the vacuum electroslag remelting, the P content is difficult to reduce, and the phosphorous phenomenon will occur due to the phosphorus contained in the electroslag, so the current nickel-based superalloy The content of P and S in the medium can only be controlled at the level of 0.015% and 0.010% respectively

[0003] It is difficult to further reduce the content of harmful elements S and P in nickel-based superalloys in the prior art, and S and P become further restrictions on the performance of superalloys An important bottleneck factor for improvement, as authoritative experts have stated, the content of P in nickel-based superalloys is reduced from 0.02% to 0.01%, and the high-temperature mechanical properties of the alloy will increase by more than 40%. It can be seen that reducing the P content in nickel-based superalloys S and P, especially P, are significant

[0004]In the existing production technology of nickel-based superalloys, it is necessary to reduce the S and P in the alloy melt in the vacuum induction melting process. At present, Ca Treatment and refining further remove S and P, but the yield is not high due to the low boiling point of Ca, and the stability of the generated CaS and Ca3P2 is not high. The ability to remove S and P is limited. Therefore, in order to further improve the effect of S and P removal in the vacuum induction melting refining process, it is necessary to use elements or alloys with stronger refining capabilities to replace the traditional single Ca treatment.