There are many different processes, that can be used on alloys to bring about desired changes in the material. One of the most important processes to consider for most parts and components is solution heat treatment.
This is used as a preliminary treatment before alloys undergo age hardening or precipitation hardening. It is critical to change the microstructure of the alloy so that only the hardening precipitates are present once the hardening process is complete. Without the initial solution annealing, existing precipitates would also be present in the final product, leading to performance and characteristic inconsistencies.
The solution heat treatment option can be used for super alloys that are nickel-based, stainless steels, aluminum and titanium alloys. It is also possible to use this process with copper-based alloys, although it is not used on every copper alloy.
How It Works
During the solution heat treatment process, it is critical to maintaining both the temperature throughout the process as well as the holding time. The various alloys require specific temperatures and holding times that are unique to the given material. This is essential to allow any existing precipitates in the material to dissolve. During this process, the material is also converted into a single-phase structure with uniform and consistent properties.
After the required temperature and holding time is achieved, the parts are then rapidly cooled through quenching. This eliminates the risk of further precipitate development in the alloy during the cooling process.
Final Product
Once the alloy is heated, held and rapidly cooled it will be a soft state relative to the original material. This soft state material is then hardened using precipitation hardening or aging processes. It is essential to carefully control the solution annealing processes as overheating the alloy can result in loss of the desired properties, including the strength and performance, of the final material.
