What are the types of heating elements for box type high-temperature resistance furnaces?

The main types of heating elements for box type high-temperature resistance furnaces are as follows:

Metallic heating element
Nickel chromium alloy heating element
Composition and characteristics: Generally composed of nickel, chromium, and other trace elements. Has high electrical resistivity, can work stably at high temperatures, strong oxidation resistance, is not easily corroded, and has a long service life.
Scope of application: Commonly used in box type high-temperature resistance furnaces with temperatures ranging from 1000 ℃ to 1200 ℃, suitable for various atmospheric environments, including oxidizing atmospheres. Widely used in fields such as electronic component sintering and metal material heat treatment.
Iron chromium aluminum alloy heating element
Composition and Characteristics: Mainly composed of iron, chromium, and aluminum. Its resistivity is higher than nickel chromium alloy, and it has good resistance to carburizing and sulfur at high temperatures, with a relatively lower price. But the high temperature strength is slightly inferior, and it is prone to embrittlement during repeated heating and cooling processes.
Scope of application: Suitable for high-temperature resistance furnaces with temperatures ranging from 1200 ℃ to 1300 ℃, commonly used in processes such as ceramic sintering and glass annealing.

Non metallic heating element
Silicon carbide heating element
Composition and Characteristics: Made of silicon carbide, it has the characteristics of high melting point, high strength, and high hardness. Good chemical stability at high temperatures, strong antioxidant capacity, and able to withstand significant temperature changes. Its resistance value increases with temperature and has a negative temperature coefficient characteristic.
Scope of application: Suitable for high-temperature resistance furnaces ranging from 1300 ℃ to 1600 ℃, commonly used in high-temperature processes such as powder metallurgy sintering and special ceramic firing.
Silicon molybdenum rod heating element
Composition and Characteristics: The main component is molybdenum silicide, which forms a dense silicon dioxide protective film on the surface at high temperatures, giving it good antioxidant properties. It can maintain high strength at high temperatures, with a small temperature coefficient of resistance and high heating efficiency. But the texture is brittle, easy to break, and has poor antioxidant capacity at low temperatures.
Scope of application: Usually used in high-temperature resistance furnaces ranging from 1600 ℃ to 1800 ℃, suitable for high-temperature oxidizing atmospheres, commonly used in high-temperature fields such as semiconductor material annealing and metal melting.