Vacuum oven is a oven in which the heat treating process takes place in the airtight vessel. The vacuum is drawn inside the vessel. The heating takes place in the controlled atmosphere. Several kinds of high temperature (refractory) materials are used for making vacuum furnace. The operable temperature are low usually without refractory insulation.

Advantages of Vacuum Furnace
Heat treatment in vacuum has its own advantages which are as follows:

• Surface reaction is prevented
• Helps in the removing of surface contaminants like oxide films and residual traces of lubricants
• Substance to the surface layers of the work is added
• Dissolved contaminating substances are removed from metals by means of degassing.

Important parameters to consider when specifying vacuum ovens include temperature range, capacity and pressure range. The temperature range is the maximum temperature at which the unit may operate and still maintain rated performances. The capacity refers to the capacity of the heated interior space of the unit.

Heat Source
Following are the heat source of the vacuum ovens:

Arc
Heating in arc configuration heat is generated by creating arc between graphite electrodes and the metal.

Electric or Resistance
Electricity is utilized for creating heat.

Induction
The main purpose of induction heating is a widely used process for the surface hardening of steel.

Applications
The common applications of the vacuum furnace are

Preheating Quenching Sterilizing Aging Annealing Brazing Soldering

Burn-off Curing Drying Firing Sintering Foundry Melting

Features common to vacuum ovens include a cooling system, shelving and racks and carts, air filtration, timers, alarms, logging and recorder options, and explosion proof construction