Heat treatment method of nickel-based single crystal superalloy

Abstract

The invention provides a heat treatment process of a nickel-based single crystal superalloy. After solution treatment, high-temperature aging treatment and low-temperature aging treatment are conducted in the vacuum inert atmosphere environment, diffusion and evaporation of Cr in the nickel-based single crystal superalloy are prevented, the surface of the nickel-based single crystal superalloy is not obviously oxidized, the depth of a Cr-poor layer is controlled to be 50 micrometers or below, and therefore requirements specified by blade technical standards are met; the dissolution of a gamma' phase with a coarse structure can be effectively promoted, element segregation and eutectic structures in a Cr-containing nickel-based single crystal superalloy structure are remarkably eliminated, the uniformity of the alloy is improved, and the influence of grain boundary strengthening elements on the nickel-based single crystal alloy is eliminated; and in addition, the nickel-based single crystal superalloy obtained through the heat treatment method has excellent high-temperature strength and oxidation resistance, the surface mechanical performance of the nickel-based single crystal superalloy is improved on the premise that creep resistance is not sacrificed, and the service life of the nickel-based single crystal superalloy is prolonged.

Description

technical field [0001] The invention relates to the field of metal treatment technology, in particular to a heat treatment method for a nickel-based single crystal superalloy. Background technique [0002] Nickel-based single crystal superalloys belong to non-equilibrium solidification during the casting process, and there is a difference between the solid phase concentration and the liquid phase concentration during solidification. Elements) and post-solidification dendrites (enriched in Al, Ta and other γ′ phase-forming elements) have composition segregation. In nickel-based single crystal superalloys, there is a certain amount of chromium element, which can make the alloy have good high temperature oxidation resistance and corrosion resistance, and improve its fatigue life at high temperature. However, during the vacuum heat treatment of single crystal blade castings, Cr depletion of the surface layer often occurs, that is, the Cr content of the surface layer of the blad...

AI Technical Summary

Problems solved by technology

But it can't solve the problem of Cr depletion on the surface layer of nickel-based alloy under vacuum addition

[0003] In the field of nickel-based alloy technology, especially in the heat treatment process of nickel-based alloys, there are still many practical problems that need to be dealt with in practical applications, and no specific solutions have been proposed.

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