Tempering is a heat-treating process applied to metals such as steel or iron based alloys to achieve greater toughness by decreasing hardness, which is usually accompanied by an increase in ductility. Tempering is commonly done after a hardening process by heating the metal to a temperature below a critical point for a certain period of time, then allowing it to cool. Untempered steel is very hard but is often too brittle for most applications. Carbon steel and cold work tool steels are often tempered at lower temperatures, while high speed steel and hot work tool steels are tempered at higher temperatures.
Aluminum, copper, brass and iron may also require tempering.
- Low-alloy steels are typically tempered in an atmosphere furnace.
- Furnaces recommended for high-alloy steels requiring vacuum tempering are Ipsen's TITAN®, TurboTreater® or MetalMaster® models. These are also preferred if you want to run multiple processes in one furnace.
- Ipsen's TITAN® LT (low temperature) vacuum furnace is recommended for tempering sensitive metals susceptible to oxidation or discoloration like stainless steel or Inconel. By using a diffusion pump, the TITAN® LT produces cleaner and brighter parts.