Effect of crystallization on thermal conductivity of diopside

Abstract

Dependence of thermal conductivity on the crystallization behavior of CaMgSi₂O₆ glass-ceramics was investigated as a function of TiO₂, V₂O₅ and MoO₃ content. With the co-addition of TiO₂, V₂O₅ and MoO₃, the glass transition temperature (T_g) was decreased, while the peak temperature of crystallization (T_p) was increased. The onset temperature of crystallization (T_c) was dependent on the types and amount of additives. Due to the differences of T_c with additives, the crystallization behaviors such as the degree of crystallization and crystallite size of the specimens were changed. The thermal diffusivity of the specimens sintered at 900°C for 1 h was increased with the crystallite size. With increasing of the degree of crystallization, the thermal conductivity of the specimens was increased, while the temperature coefficient of thermal conductivity was decreased.