Solution Annealing Heat Treatment Process
Many stainless steel castings require either solution annealing or homogenizing after the casting process.
Homogenization is commonly used on precipitation hardening stainless steels like 17-4 and 15-5 to resolve alloy segregation and dendritic structures and homogenize the chemical composition and microstructure. The temperature ranges for this process are often in excess of 2000F. ThermTech has the ability to run this process in some large open-fire furnaces that can handle parts up to 46" wide x 42" high x 92" long.
Solution Annealing stainless steel castings is a process which takes the carbides that have precipitated in the grain boundaries and dissolves then into the surrounding matrix. The austenitic stainless steel castings are typically solution annealed at temperatures between 1900F to 2100F and rapidly cooled to prevent a repeat of carbide precipitation in the grain boundaries. Some alloys due to their low carbon content do not need a solution anneal due to carbide formation, but benefit from a solution anneal to achieve maximum corrosion resistance.