Thermomechanical characterization of a fire clay refractory made of Algerian Kaolin
Résumé
The thermomechanical behaviour of a mullitic refractory made of Algerian kaolin was investigated. Bending tests reveal that the behaviour was linear until 900 °C and became visco-plastic at 1000 °C. A maximum of strength (33 MPa) was reached at 900 °C where a crack bridging strengthening process was reported. The elaborated refractory presents a maximum elastic modulus of (8.21 GPa) at 700 °C due to the crack healing phenomenon. The calculated apparent activation energy for creep deformation is about 335 kJ/mole (T < 1050 °C). For the highest temperature (> 1050 °C), an increase of the activation energy was recorded. Cyclic thermal shocks realized from 950 °C into a water bath kept at ambient temperature show that the elaborated refractory can be classified as a good thermal shock resistant material. © Lavoisier, Paris.