The air in our atmosphere is made up of elements that are critical to maintaining life on this planet, but when some of those elements come into contact with other elements, chemical reactions take place that can change their properties. This is especially true in the heat treatment process.
When metals undergo excessive heat to be manipulated, this necessary process can expedite metal’s reaction to the air, rapidly accelerating the oxidation process and changing the properties of the metal on its surface.
However, if you remove the air from around the metal during heat treatment, you can protect the metal from these changes.
In vacuum heat treatment, air—specifically, the oxygen—around the metal is removed from the furnace to create a vacuum. The parts are heated in the vacuum with or without an inert gas (typically argon or nitrogen) to achieve the desired properties while protecting the parts’ surface. After heating, the parts are then quenched, or cooled, in the vacuum environment.
Depending on the needs and properties the parts require, this process can take anywhere from 3 to 24 hours.
Because of its high thermal efficiency, vacuum heat treatment is an extremely environmentally friendly method of heat treatment. It also improves material strength. Parts heat treated in a vacuum don’t require any further forming, and there’s no post-process cleaning required because the parts come out clean.
Vacuum heat treatment is most often used for air hardening steels, metal based super alloys, and reactive and refractory materials like titanium. Parts that have to withstand high temperatures and other stressors during operation also benefit from vacuum heat treatment. It is one of AST’s valuable processing options for the heat treatment of aircraft and other high precision parts.
Akron Steel Treating is accredited by Nadcap, which ensures we are in compliance with customer requirements and industry standards in the aerospace industry. Heat treatment is our specialty—connect with us to learn more about how we can partner together to complete your projects.« Back to General