Effect of temperature on measuring the thermal diffusivity of ceramic of different specimen thicknesses by using a laser-pulse method

Effect of temperature on the thermal diffusivity of (Sr, K)Zr4(PO4)6 ceramic (abbreviated as SrKZP) of different specimen thicknesses ranging from 0.68 to 3.0 mm has been investigated using a laser-pulse method with different pulse energies. The thermal diffusivity of the ceramic shows a strong dependence on the specimen thickness as well as pulse energy at room temperature, which is attributed to excessive rise in the specimen temperature (ΔT) associated with a non-linear detector response. However, such a dependence becomes weak at elevated temperatures. The thermal diffusivity (α) of the ceramic illustrates a strong thickness-dependence with ΔT ⇒ 0α0), i.e. α0 increases with increasing specimen thickness for increasing specimen thickness for various temperatures. The thickness-dependent diffusivity of the SrKZP ceramic is modified by considering radial heat conduction effect, resulting in values of thermal diffusivity which are independent of specimen thickness at various temperatures.