1. What is kiln furniture?
Kiln furniture refers to the collection of heat-resistant supports and structures used inside a kiln to hold and position ceramic, pottery, or glass items during firing. Kiln furniture is typically made from refractory materials that can withstand high temperatures without warping, deforming, or disintegrating. Kiln furniture can account for up to 80% of the mass of a kiln charge.
2. Materials of kiln furniture
Commonly used materials are cordierite (up to 1280 °C), mullite (up to 1750 °C), silicon carbide (up to 1600 °C), alumina (up to 1750 °C), zirconia(up to 2400 °C).
1) Cordierite-mullite kiln furniture
Cordierite is a magnesium aluminum silicate mineral (Mg2Al4Si5O18) that possesses a low coefficient of thermal expansion. It is known for its ability to withstand rapid temperature changes without cracking or breaking. Cordierite has a high thermal shock resistance, making it suitable for applications where there are significant temperature variations, such as in kiln firings.
Mullite, on the other hand, is an aluminum silicate mineral (Al6Si2O13) that exhibits excellent high-temperature stability. It has a low thermal expansion coefficient, high melting point, and good mechanical strength. Mullite also provides good resistance to chemical attack, making it suitable for use in harsh environments.
By combining cordierite and mullite, the resulting cordierite-mullite composite material takes advantage of the desirable properties of both minerals. The cordierite component provides thermal shock resistance, while the mullite component contributes high-temperature stability and strength.
Cordierite-mullite kiln furniture is commonly used in ceramic and glass manufacturing industries.
2) Silicon Carbide kiln furniture
Silicon carbide is a compound composed of silicon and carbon atoms and is known for its exceptional properties, such as high-temperature stability(from 1300-1600℃), excellent thermal shock resistance, superior strength, and rigidity, chemical inertness, which makes it suitable for high-temperature applications, including kiln furniture.
3) Alumina products
Alumina (Al2O3) is a widely used technical ceramic known for its high-temperature stability, good mechanical strength, and excellent insulating properties.
4) Zirconia products
Zirconia(ZrO2) typically exhibits excellent mechanical properties and stability at high temperatures.
The maximum working temperature for zirconia products typically ranges from 1800°C to 2400°C, depending on the specific composition and grade of the zirconia material used.
3. Kiln furniture components include:
Kiln shelves, plates, cover batts, props, fittings, profile setters, fish cranks, Y-cranks, pin cranks, saggers, rollers, beams, supports, tubes, rods, burners, etc.
