Method for melting nickel-base high temperature alloy with electro-slag furnace

Abstract

The invention relates to a method for melting a nickel-base high temperature alloy with an electro-slag furnace. The method includes the following methods: loading materials, welding a high temperature alloy electrode and a false electrode to be smelted together, and placing slag materials at the bottom of a crystallizer; blowing the welded electrodes with inert gases, and closing a protection cover; protecting a smelting closing smoke exhaust valve, and feeding an Ar gas into the crystallizer and the protection cover; striking an arc and melting slag; cleaning smelting slag materials, starting a smelting period, and swinging a slag resistor for less than 0.5 m omega during the smelting process; adding oxidizing agents, and adding metal aluminum powder continuously or at intervals to serve as deoxidizing agents during an electro-slag re-melting process; adopting feeding thorough three stages, power feeding is decreased rapidly, power feeding is decreased slowly, and finally heat is preserved at constant power; and casting a die, cooling and demolding the die. According to the method for melting the nickel-base high temperature alloy with the electro-slag furnace, the surface of a nickel-base high temperature steel ingot has no slag groove defect, and the burning losses of Al and Ti are less than or equal to 5%.

Description

technical field [0001] The invention discloses a method for smelting a nickel-based superalloy in an electroslag furnace. Background technique [0002] The difficulty of electroslag remelting superalloys is that the alloy in the superalloy is ≥20ppm, the steel ingot segregates seriously, the hot workability is poor, it is easy to crack during forging, the forging yield is ≤ high, and it contains Nb, Ti, Mo and other elements that are easily segregated. Improper selection of the electroslag process will cause severe segregation of the steel ingot, resulting in defects such as black spots; it contains Al, Ti and other elements that are easy to burn, and the composition of the ingot head and tail has a large deviation. At present, the main problem of electroslag remelting superalloys is that slag groove defects appear on the surface of steel ingots, the burning rate of Al and Ti is 10%, the deviation of Al and Ti at the head and tail of electroslag ingots is greater than ±0.08%...

AI Technical Summary

Problems solved by technology

[0002] The difficulty of electroslag remelting superalloys is that the alloy in the superalloy is ≥20ppm, the steel ingot segregates seriously, the hot workability is poor, it is easy to crack during forging, the forging yield is ≤ high, and it contains Nb, Ti, Mo and other elements that are easily segregated. Improper selection of electroslag process will cause severe segregation of steel ingots, resulting in defects such as black spots; it contains Al, Ti and other elements that are easy to burn, and the composition deviation of the ingot head and tail is large

At present, the main problem of electroslag remelting superalloys is that slag groove defects appear on the surface of steel ingots, the burning rate of Al and Ti is 10%, the deviation of Al and Ti at the head and tail of electroslag ingots is greater than ±0.08%, and the sulfur content of products is 60%.