A fire brick is a block of refractory ceramic material used in lining furnaces, kilns, fireboxes, and fireplaces. A refractory brick is designed mainly to withstand high heat, but should also usually have a low thermal conductivity to save energy. There are to main types of Fire Bricks in the Market i.e.
1). 40% Alumina Fire Brick (Sevice Temp. of upto 1300 degrees ) of standard dimensions of 230*115*75mm
2).70% Alumina Fire Bricks (Sevice Temp. of upto 1750 degrees )of standard dimensions of 230*115*75mm
Usually dense bricks are used in applications with extreme mechanical, chemical, or thermal stresses, such as the inside of a wood-fired kiln or a furnace, which is subject to abrasion from wood, fluxing from ash or slag, and high temperatures. Dense refractory bricks have a high thermal mass which is sometimes a useful property in that they will retain heat eg in a pizza oven after the fire has been taken out. Refractory bricks usually contain 30-40% alumina and the primary raw material is usually chamotte with other materials. The maximum service temperature increases with increasing alumina content and kiln bricks can be obtained with an alumina content of 80% and above.