Due to the high melting point of the original components of nickel base alloy and the high requirement for its purity, the nickel base alloy smelting process is very unique compared with the conventional smelting method. "Special steel 100 seconds" summarized below, the main process has three:
1. Vacuum induction melting (VIM)
Vacuum induction melting (VIM) is a melting method which USES electromagnetic induction to produce eddy current heating furnace materials inside metal conductors in vacuum conditions.
VIM provides maximum control over the chemical composition and prevents contact between the molten solution and atmospheric hydrogen, oxygen and nitrogen. Electromagnetic stirring can not only make the molten liquid uniform, but also continuously bring the reactants to the melt and the vacuum interface, so that the subsequent refining reaction can be carried out smoothly. The gas content and the volatilization and precipitation of nonmetallic inclusions can greatly improve the mechanical properties of most superalloys.
2. Electroslag remelting (ESR)
Electroslag Remelting (company - Slag Remelting, the ESR for short) is the use of an electric current passes through the Slag resistance of heat as a heat source method for smelting, is a current through the liquid Slag pool Slag resistance heat, melt the metal electrode and molten metal to assemble drop, drip through a Slag layer into the metal molten pool, and then the cooling crystallization of solidified into steel ingot mould. Electroslag metallurgy is the important means of production of high quality material, high temperature melting, chemical refining and condensing crystallization combining production high quality ingot casting, has high purity, low sulfur content, non-metallic inclusion, ingot surface is smooth, uniform crystallization, the advantages of uniform microstructure and chemical composition, are widely used in aerospace, military industry, energy, shipbuilding, electronics, petrochemical, heavy machinery and transportation, etc. The important areas of the national economy.
3. Vacuum consumable arc melting (VAR)
Vacuum since the electricity Arc smelting (Vacuum Arc Remelting, referred to as the VAR) is under the Vacuum state, using the dc power supply in the electrodes and placed in the water jacket copper crucible bottom between Arc, Arc heating heat, producing consumable electrode, electrode is declining, melting molten pool formed inside the water cooled copper crucible, molten metal finish quick-setting, crystallization, solidified ingot.
