What is Chamotte?
Chamotte—also known as ‘grog’ and ‘firesand’—is calcined clay containing a high proportion of silica and alumina. It is produced by firing selected fire clays in a rotary kiln to temperatures between 1,400°C and 1,600°C, before grinding and screening to specific particle sizes.
Typical chamotte contains 40% minimum alumina, 30% minimum silica, 4% maximum iron oxide, and up to 2% calcium oxide and magnesium oxide combined. The particle size distribution is generally coarser in size than other raw materials used to prepare clay bodies.
Excellent thermal stability
Excellent thermal shock resistance
High mechanical resistance
- Kiln furniture
- In the production of sanitaryware pieces, Imerys chamottes are used to produce fine fire-clays which act like a skeleton, enabling the production of large, complex pieces such as baths and shower trays with enhanced mechanical properties. Fine fire-clays are more suited to the production of large, more sophisticated designs than vitreous ceramics.
- The tile industry also uses chamottes, particularly for the production of extruded tiles.
Cordierite-chamotte materials are the main constituents of high thermal shock resistant kiln furniture.