What is the production process for nickel based corrosion-resistant alloys?

 　　According to the chemical composition of the alloy, especially the content of elements such as C, S, P, S, and the requirements for purity, electric arc furnace, vacuum induction furnace, or secondary refining process can be used for smelting. To ensure good thermal and plastic properties of corrosion-resistant alloys, the deoxidation process must be strictly controlled during smelting. Some alloys require the addition of an appropriate amount of Al or Ca, Mg, rare earth, etc. as the final deoxidizer. Some alloys can significantly improve their thermoplastic properties using the electroslag remelting process.

　　Nickel based corrosion-resistant alloys are prone to combine with sulfur in the furnace gas during heating, forming low melting point nickel sulfide, which can crack during processing. Therefore, electric furnaces, protective gas furnaces, or low sulfur fuel furnaces should be used for heating. The temperature range of hot working is shown in Table 1. This type of alloy usually has good cold working performance. After each solution or annealing treatment, the allowable cold working deformation is generally between 20% and 80%.

　　How about the heat treatment process?

　　This alloy is subjected to solid solution heat treatment to maximize the confinement of various precipitates in the alloy, thereby achieving good corrosion resistance and mechanical properties. However, due to the significant impact of grain size on the resistance of alloys to intergranular corrosion and stress corrosion, some alloys often use lower solution treatment temperatures to refine their grains. In addition, precipitation hardening corrosion-resistant alloys require both corrosion resistance and high hardness, so the process of one or two aging treatments after solid solution is often used.