Thermal Properties of ceramic materials

THERMAL PROPERTIES

Since the ceramic materials contain relatively few electrons, their thermal properties differ from that of metals. The most important thermal properties of ceramic materials are

(i) Thermal capacity

(ii) Thermal conductivity

(iii) Thermal Shock

 (i) Thermal capacity

• The specific heats of fine clay bricks are 0.25 at 1000°C and 0.297 at 1400°C.

• Carbon bricks possess specific heats of about 0.812 at 200°C and 0.412 at 1000°C.

 (ii) Thermal conductivity

• The ceramic materials possess a very low thermal conductivity since they do not have enough free electrons.

• The impurity content, porosity and temperature decrease the thermal conductivity.

• The ceramic materials possess low thermal conductivity sliaus due to its low density.

(iii) Thermal Shock

"Thermal shock resistance" is the ability of a material to resist cracking or disintegration of the material under sudden changes in temperature.

• Lithium compounds are added in many compounds to reduce thermal expansion and provide excellent thermal shock resistance.