Open Firing Ceramics Definition

This is where the magic happens.

Open firing ceramics definition.

When loading the kiln it is important to handle the pieces carefully so the glaze does not come loose. The pre firing of a ceramic material to remove all moisture and burn off any oxides and gases. A modern technical definition is a vitreous or semi vitreous ceramic made primarily from stoneware clay or non refractory fire clay. It s important that the temperature rises slowly and cools slowly.

Ceramic work is typically fired twice. The glaze firing is the most exciting part of the process for a lot of people. While it is true that pottery fired outdoors breaks more often than pottery fired in a kiln the breakage rate can be drastically reduced by taking certain precautions. Stoneware is a rather broad term for pottery or other ceramics fired at a relatively high temperature.

To the human eye pots and other clay objects do not look melted. It may or may not be glazed. When it comes to bisqueing in essence the noun refers to any sort of pottery that you ve fired once and that has nothing chemically bonded in terms of water left within the clay. Whether vitrified or not it is nonporous does not soak up liquids.

The firing process is measured in cones a standard unit of measurement that accounts for time and temperature. The purpose of this initial firing is to turn your pottery into ceramic material. In essence it s already been fired once and you re just going to put the glaze on it in order to fire it again. The final aim is to heat the object to the point that the clay and glazes are mature that is that they have reached their optimal level of melting.

Both of these issues are easily dealt with. It is bisque fired and then glaze fired. Most breakage in open outdoor pottery firings occurs because of either moisture in the clay or thermal shock. The melting that occurs is on the molecular level.

Forming pottery by pouring slip into a porous mould usually made from potters plaster. When the ceramic is fired a process known as vitrification takes place whereby the glass phase liquefies and fills the open spaces between the particles. If you can have the students take a look at the loaded kiln before the firing and then again when you open the lid. Click on the image to the left to see the vitrification process.

Firing converts ceramic work from weak clay into a strong durable crystalline glasslike form. Failure to do so could cause the piece to burst putting you back at square one. A very fluid slip of high specific gravity obtained by deflocculation and used for forming ware using the casting process.