The process of melting nickel alloys

1. Melting method: The melting of nickel-based alloys usually adopts vacuum induction melting (VIM), electroslag remelting (ESR) and vacuum consumable arc melting (VAR). These methods can maintain the purity of the alloy at high temperatures while preventing oxidation and contamination of the alloy components.

2. Preparation before melting: Before melting, raw materials need to be pre-treated, such as drying to remove moisture and impurities, to reduce pores and inclusions in the melting process.

3. Melting process control: In the melting process, it is necessary to precisely control the melting temperature and atmosphere to ensure the chemical composition and physical properties of the alloy. Inert gas protection, such as argon, is usually used to prevent the alloy from coming into contact with the air, thus avoiding oxidation.

4. Processing after smelting: After smelting is completed, the alloy usually needs to be forged, rolled or other hot working processes to improve its microstructure and mechanical properties. These processes can break the cast structure and optimize the microstructure.

5. Heat treatment: Nickel-based alloys usually require heat treatment after processing, including solution treatment and aging treatment, in order to obtain the required mechanical properties and corrosion resistance. Solid solution treatment can dissolve the precipitated phase back and improve the toughness and anti-creep performance, while aging treatment can precipitate the strengthened phase and improve the strength.

6. Quality control: Throughout the smelting process, strict quality control is required, including chemical composition analysis, metallographic microstructure inspection and performance testing to ensure that the alloy meets the specific application requirements.

Nickel-based alloys are widely used in aerospace, chemical, energy and other industries because of their excellent strength and corrosion resistance at high temperatures. The optimization of melting process is very important to improve the properties of alloys.