Contents:

1. Earthenware, pottery,porcelain, ceramics - which ingredients are needed to allow molding and what happens during burning ? Claudia Eisermann

2. Contents: • Overall view • Pottery • Porcelain • Ceramics • Which ingredients allow molding ? • Burning Claudia Eisermann

3. Overall view • Earthenware: - used for pottery - made from clay - slightly porous after first firing (not vitrified) - glaze before second firing -> waterproof Claudia Eisermann

4. Overall view • Porcelain: - made from mixture of kaolin and petuntse - differences to stoneware less clear - pottery, resonant against pushes - vitrified pottery Claudia Eisermann

5. Overall view • Ceramics: - differences to porcelain in roughness and stability - important material: clay - depending on use high quality claim - able to produce wanted color (porcelain too) Claudia Eisermann

6. Pottery • History: - before Christ: vessel - 15th century: decoration; first mould - 18th century: moulds of plaster - 19th century: mechanization (England) • Important ages: - ancient world, renaissance (Donatello, Luca della Robbia) Claudia Eisermann

7. Pottery • Production: - red clay (Fe) or yellow clay (lime) - clay dug out, dried, ground - water added, mixed 1) moulds: equal layer -> plaster takes water -> pottery shrinks -> precision work 2) handwork: forming with hands, wet cloth, wooden spatula, slow drying before burning Claudia Eisermann

8. Pottery • Burning: - dry products (water evaporates ->cracks) - 1000°C, 5 – 10 days - slow cool down - to high temperature -> vitrification - to low temperature -> porous - pottery in cool water -> lime extinguished -> pores density increases Claudia Eisermann

9. Pottery • Properties: - easy to form - natural warm color - long durable - water-resistant - resistant against frost (high density -> less water taken up -> small expansion) Claudia Eisermann

10. Pottery • Use: - vessels, statues of animals - oil lamps - art, decoration, jewelry - building materials and commercial materials: tiles, plates for covering, washbasin, vases, pots Claudia Eisermann

11. Porcelain • called “white gold” • noble products are hard porcelain and Bone China (made with ash of bones; England) • famous factories: Meißen, Fürstenberg, Frankenthal Claudia Eisermann

12. Porcelain • History: - developed in year 620 in China - 1708 in Europe, by Ehrenfried Walther von Tschirnhaus - continued by Johann Friedrich Böttger - 1710, Meißen: first manufacture in Europe (which became famous in the world) Claudia Eisermann

13. Porcelain • Hard porcelain: - Kaolin (50%), feldspar (25%), quartz (25%) - third burning temperature: 1410 °C • Soft porcelain: - Kaolin (40%), feldspar (30%), quartz (30%) - third burning temperature: 1300 °C Claudia Eisermann

14. Porcelain • Production: - mixture of 3 materials - forming by hand (spinning slice) or by machines (pressure) - first firing (850 – 950 °C), cool down (slow) - second firing (1300 – 1410 °C) - glaze applied - painting + glaze - third firing (780 – 1410 °C, depending on glaze) Claudia Eisermann

15. Porcelain • Forming by hand: - compact mass - pliable • Foundry: - liquid mixture - hollow products (solid edge -> liquid rest decanted) Claudia Eisermann

16. Porcelain • Properties: - thick fragments - shell-shaped break - high roughness - constant against acids and lye - bright sound - constant against high temperatures - isolation against electricity Claudia Eisermann

17. Porcelain • Use: - decoration - isolator - dishes - chemical device (crucible) Claudia Eisermann

18. Ceramics • History: - before Christ: rotating potter´s wheel in China - 16th century: fly wheel - 19th century: pedal -> two free hands - 20th century: electric motor (regular speed) Claudia Eisermann

19. Ceramics • Production: - clay, water - mixture cast/formed/pressed - burning (600 °C) -> moisture removed - 2nd burning -> smooth surface - decoration (stamp, carving, cut parts out) - glaze Claudia Eisermann

20. Ceramics • Properties: - high roughness - resistant against weather - bears high temperatures - electrical isolation - very low wear - dimensional stability - adapted to the use (raw materials, production) - different colors Claudia Eisermann

21. Ceramics • Use: - mechanical engineering, process engineering - electronics - high temperature technique - building materials: tiles, plates - sanitary, appliances in the household (dishes) - pots Claudia Eisermann

22. High-performance ceramic • since 1960 • properties depend on use • efficient • example: dental ceramic - 1st burning: 1100 °C - 2nd burning: 1700 °C Claudia Eisermann

23. ingredients • bigger than product (water evaporate) • chamotte -> little loss • organic additives: deflocculant, binding agent • 1st burning -> additives removed • green body (formed, not burned) Claudia Eisermann

24. Burning • raw material compacted, less porous • adapted temperature, pressure, time • carbon built in the material -> stable • coking (about 1000 °C) -> organic additives turn to carbon Claudia Eisermann

25. Burning • clay + silicic acid -> Silimanit (Al2O3*SiO2), Mullit (3 Al2O3*2 SiO2) = double chains of silicate Claudia Eisermann

26. research/development • improve specifications • resistant against acid • corrosion protection • electrical isolation • ceramic industry connected with chemistry Claudia Eisermann

27. sources • Hollemann, Wiberg; Lehrbuch der anorganischen Chemie, de Gruyter, 1985 • http://de.wikipedia.org/wiki/Porzellan • http://de.wikipedia.org/wiki/Keramik • http://www.frankreich-sued.de/Limoges/Porzelan.htm • http://www.toepferhof-online.de/Ofen/ofennabe.html • http://www.uni-protokolle.de/Lexikon/Porzellan.html • http://www.uni-saarland.de/fak8/powdertech/projekte/projekt_oetzel_client.html • http://www.unileoben.ac.at/~buero41/daabs/winter.htm • http://www.komage.de/zahnkeramik.php • http://www.crystec.com/kllcerad.htm • http://www.fbi-biomaterialien.de/ima/weblication/deutsch/mains/2_charakterisierung.htm • http://www.fz-juelich.de/zb/text/publikation/juel3227.html Claudia Eisermann