Vacuum furnace
From Wikipedia, the free encyclopedia
A Vacuum furnace is a type of furnace that can heat materials, typically metals, to very high temperatures and carry out processes such as brazing, sintering and heat treatment with high consistency and low contamination. [1]
In a vacuum furnace the product in the furnace is surrounded by a vacuum. The absence of air or other gas prevents heat transfer with the product through convection and removes a source of contamination. Some of the benefits of a vacuum furnace are:
- Uniform temperatures in the range 2000–2800°F/1100–1500°C
- Temperature can be controlled within a small area
- Low contamination of the product by carbon, oxygen and other gases
- Quick cooling (quenching) of product.
- The process can be computer controlled to ensure metallurgical repeatability.
Heating metals to high temperatures normally causes rapid oxidation, which is undesirable. A vacuum furnace removes the oxygen and prevents this happening.
An inert gas, such as Argon, is typically used to quickly cool the treated metal back to non-metallurgical levels (below 400 °F) after the desired process in the furnace.[2] This inert gas can be pressurized to 2 times atmosphere or more then circulated through the hot zone area to pickup heat before passing through a heat exchanger to remove heat. This process is repeated until the desired temperature is reached.
