Kiln furniture is ceramics kiln functional refractory products, which’s main function is separation, support and protection of ceramic wares green body during high temperature sintering in ceramic kiln. By materials compositions, kiln furniture can be divided into different categories. Clay kiln furniture made by chamotte and clinker (waste saggers, waste clay) can be used at about 1300℃. High alumina kiln furniture, which’s Al2O3 content is higher than 46%, can be used at temperature under 1450℃. Mullite kiln furniture, which’s main crystalline phase is mullite(10 % kaolin, 90% synthesized mullite), has good mechanical strength and can be used between 1400~1500℃. Cordierite mullite kiln furniture, which’s principle crystalline phase is cordierite and mullite, can be used below 1310℃. Silicon carbide kiln furniture and re-crystallized silicon carbide kiln furniture have extraordinary good thermal shock resistance and high strength, can be used below 1400℃. Re-crystallized silicon carbide kiln furniture’s short term max. working temperature can reach to 1650 ℃. Long term max. working temperature of silicon nitride binding silicon carbide kin furniture can reach to 1550℃.
By function, kiln furniture can be classified into tiles kiln furniture, bricks kiln furniture, solid shed board, hollow shed board, batts, props, plate sagger, profile setters, sintering trays and so on.
Kiln Furniture Characteristics
Good thermal shock resistance, room temperature and high temperature mechanical strength.
Excellent thermal conductivity and air permeation ability.
High refractoriness and refractoriness under load(RUL), RUL temperature should be 50~100 ℃ higher than ceramics sintering temperature.
Lightweight, low specific heat capacity, accurate size and nice regularity.
Kiln furniture max. Working Temperature
Item
Clay kiln furniture
High alumina kiln furniture
Mullite kiln furniture
Cordierite mullite kiln furniture
Silicon carbide kiln furniture
Material
Clay, sagger
Bauxite
Mullite, bauxite
Cordierite, mullite
Silicon carbide
Al2O3 % ≥
/
46
/
/
/
Max. working temperature ℃
1300
1450
1400~1500
1310
1400
Kiln Furniture Application
Ceramics industry kiln furniture pieces should endure harsh conditions, repeated heating and cool cycles, the main damages are cracking, bending, dirt accumulation and surface glazing due to oxidation and other chemical reaction. So, for service temperatures up to 1300°C, cordierite mullite furniture which has very small thermal expansion and excellent thermal shock resistance is popularly used.
