19.2 Porcelain Dinnerware
The most popular type of dinnerware made in Asia and Europe is hard porcelain. Porcelain dinnerware is fired three times with the bisque firing being only to 800-1000°C. Since the body is only partially vitrified in the kiln furniture is required and the product can be stacked bisque firing, no can be handled The bisque firing is only high enough so the product Typical bisque cycles are 8-20 hours in tunnel kilns. The second firing is the glost firing to approximately 1250°C and is also done in tunnel kilns. The product is fired in n furniture which totally supports the piece. Typical firing cycles are 8-15 hours long. The kin atmosphere is oxidizing up to 1000°C, reducing from 1000 to 1280°C, and oxidizing during the cooling. The verification of the body is completed the glost firing along with the development of the glaze. Porcelain dinnerware is usually decorated over glaze with the decoration firing around 760 800°C. Belt kilns and roller hearths are used with the cycle times being in the 2 to 4 hour category.