Ceramic Firing Temperature

Cone temperature conversion chart.

Ceramic firing temperature.

Ware and glaze types. Firing converts ceramic work from weak greenware into a strong durable permanent form. If the temperature goes too high the glaze will become too melted and run off the surface of the pottery. Clay bodies have ranges of temperature that they can be fired to.

Mid fire earthenware should be fired between cone 2 and cone 7. First it is important to know that the maximum cone rating of a stoneware or porcelain clay is the temperature at which it vitrifies. A common temperature range for industrial ceramics. As the temper ature in a kiln rises many changes take place at different temperatures and understanding what happens during the firng can help you avoid problems with a variety of clay and glaze faults related to firing.

The glass phase that forms during the firing of a ceramic material can be thought of as the glue that holds the finished work together. This is the most common temperature range for industrial ceramics. People want to know if they can fire a certain clay to a certain cone. When potters talk about ceramic firing ranges they are usually referring to the three most common.

We get many questions about clay firing temperatures. The ware is returned to the kiln for a very low temperature firing in order to fuse the overglazes. For mid range material a kiln should be firing at a temperature between 2124 and 2264 1162 1240. Stoneware glaze some decals fire to cone 10.

And a body clay with underglaze yellow orange to light yellow from this point up low fire clays will start to melt damaging shelves and other pots low fire clays mature. This is the hardening tightening and finally the partial glassification of the clay. Each ceramic glaze should be fired to a specific temperature range. Firing temperatures cone equivalents showing various clays and glazes mid range stoneware porcelain clays mature vashon clays crystal white dove alpine white etc.

You cannot fire pottery in a home oven because ovens do not get up to the high temperatures of more than 1 500 degrees fahrenheit that you need for firing clay. If fired at too low a temperature the glaze will not mature. Average is cone 10 2381 f 1305 c cone 8 12 range 2305 22419 f 1263 1326 c a hard vitrified non absorbent clay body. The fancy name for this is vitrification or the ceramic chemistry that transforms a clay body into a hard non crystalline glass.

Low fire mid range and high fire ranges. Cone 10 13 range 2381 2455 f 1305 1346 c. The temperature needed to transform soft clay into hard ceramic is extremely high and is usually provided by a kiln. Mostly yellow with a hint of orange.

For success a potter must know their glazes temperature ranges at which they become mature.