Process for preparing nickel-base superalloy

Abstract

The invention discloses a process for preparing nickel-base superalloy. The superalloy consists of the following components in percentage by weight: 22.5 to 24.5 percent of Cr, 7.0 to 8.0 percent of Co, 6.5 to 7.5 percent of W, 3.0 to 4.0 percent of Mo, 1.2 to 1.8 percent of Al, 1.5 to 2.5 percent of Ti, 2.0 to 3.0 percent of Nb, 1.0 to 2.0 percent of Mn, 2.0 to 4.0 percent of Fe, 0.02 to 0.08 percent of B, 0.5 to 1.5 percent of Ce, less than or equal to 0.1 percent of C, less than or equal to 0.2 percent of Si, less than or equal to 0.008 percent of P, less than or equal to 0.008 percent of S and the balance of Ni. The process for preparing the nickel-base superalloy comprises a smelting process and a heat treatment process, wherein the smelting process comprises the steps of: smelting master alloy by using a vacuum induction furnace, and performing directional solidification in a liquid metal directional furnace to prepare directional column crystal alloy, wherein the vacuum degree of the directional furnace is about (1-5)*10<-4>mmHg, the pouring temperature is 1,580 to 1,600 DEG C, the drawing speed is 4 to 8mm / min, the temperature gradient is 75 to 85 DEG C / cm, and the temperature of liquid tin is 250 to 350 DEG C; the heat treatment process comprises the following steps of: heating the column crystal alloy obtained through smelting to 1,240 to 1,260 DEG C, preserving heat for 3 to 5 hours, and performing air cooling to room temperature; heating to 1,150 to 1,170, preserving heat for 3 to 5 hours, and performing air cooling to room temperature; and heating to 930 to 950 again, preserving heat for 8 to 12 hours and performing air cooling to room temperature.

Description

technical field [0001] The invention relates to the field of alloys, in particular to a preparation process of a nickel-based superalloy. Background technique [0002] The Inconel718 alloy was successfully developed by the Houston Branch of the American International Nickel Corporation and was published in 1959. It is a body-centered square Ni 3 Nb(γ”) and face centered cubic Ni 3 (Al,Ti,Nb)(γ') precipitation strengthened nickel-chromium-iron based wrought superalloys. The alloy has high tensile strength, yield strength, durable strength and plasticity at -253-650°C, and has good corrosion resistance, radiation resistance, thermal processing and welding properties. [0003] In the context of the rapid development of superalloy overall precision casting technology, Inconel718 alloy, originally developed as a deformed superalloy, has also been used in the aerospace industry in the form of casting alloy since 1965. The corresponding casting alloy grade is Inconel718C. In rec...

AI Technical Summary

Problems solved by technology

With the development of technology, higher and higher requirements are put forward for the alloy of the combustion chamber wall. The traditional Inconel718 and corresponding alternative alloys can no longer meet the demand. Therefore, it is necessary to develop new superalloy materials