A vacuum sintering furnace is an industrial furnace capable of reducing the working pressure inside the chamber below atmospheric pressure. It uses electric heating, ensuring that the surface of heated components is free from oxidation and decarburization, with minimal deformation and excellent mechanical properties. Metals smelted in a vacuum furnace benefit from impurity removal, resulting in fewer defects, reduced segregation, and improved product quality.
Vacuum sintering furnaces are suitable for smelting and heat-treating high-quality, high-purity, and refractory metals—such as tungsten, molybdenum, tantalum, niobium, titanium, and heat-resistant alloy steels. They are also widely used in the processing of magnetic materials, electrical materials, high-strength steel, stainless steel, and tool steels.
Vacuum sintering furnaces emerged in the 1930s.
- In 1927, the United States developed the first vacuum annealing furnace for electrical materials.
- By 1953, vacuum consumable arc furnaces were used in industrial production to smelt sponge titanium.
- During the 1950s, vacuum induction furnaces gained widespread industrial application.
- In 1960, the United States successfully developed an oil-quenching vacuum sintering furnace.
Structure and Features
A typical vacuum sintering furnace consists of:
- Furnace chamber
- Electric heating system
- Sealed furnace cover
- Vacuum system
- Power supply system
- Temperature control system
The sealed furnace cover is welded from carbon steel or stainless steel. All detachable interfaces are sealed with vacuum sealing elements. To prevent deformation of the cover and thermal degradation of sealing materials, the furnace cover is usually cooled by water or air. The furnace chamber is located inside the sealed cover.
Depending on application requirements, various heating elements can be installed inside the chamber, such as resistance heaters, induction coils, metal electrodes, or electron beam guns. Furnaces used for metal smelting are equipped with crucibles, and some models may also include automated pouring systems and robotic loading/unloading devices.
The vacuum system is typically composed of vacuum pumps, vacuum valves, and vacuum gauges.