Carregant...
Miniatura

Tipus de document

Article

Versió

Versió acceptada

Data de publicació

Tots els drets reservats

Si us plau utilitzeu sempre aquest identificador per citar o enllaçar aquest document: https://hdl.handle.net/2445/180610

Thermal behaviour of ceramics obtained from the kaolinitic clays of Terra Alta, Catalonia, Spain.

Títol de la revista

Director/Tutor

ISSN de la revista

Títol del volum

Resum

The thermal properties and evolution of mineralogy and colour of kaolinitic clay from the Terra Alta region were studied. The mineralogy of these materials consists mainly of kaolinite (13-27 mass%) and quartz (48-86 mass%). Minor illite, hematite, K-feldspar and calcite also occur. The linear expansion and absorption curves were used to predict the optimal firing temperature of the raw clays. During firing, from 1100 °C the water absorption decreases steeply, due to an increase in liquid phase, which penetrates into the pores and close the porosity. At this temperature, the firing shrinkage increases progressively. The fired clays are mainly composed of quartz, cristobalite and mullite, with minor hematite and rutile. Mullite starts to appear at 1050-1100 °C. SEM observations show that porosity decreases with the firing temperature. The colour properties were measured in the raw clays and in the fired bricks at different temperatures. The lightness, L*, is lower in the fired test pieces respect to the natural clays. This colour varies according to the hematite content, being from white to reddish in the fired samples.

Citació

Citació

GARCIA VALLÈS, Maite, CUEVAS, D., ALFONSO ABELLA, María pura, MARTÍNEZ MANENT, Salvador. Thermal behaviour of ceramics obtained from the kaolinitic clays of Terra Alta, Catalonia, Spain.. _Journal of Thermal Analysis and Calorimetry_. 2021. [consulta: 21 de gener de 2026]. ISSN: 1388-6150. [Disponible a: https://hdl.handle.net/2445/180610]

Exportar metadades

JSON - METS

Compartir registre