Study On Thermal Conduction Properties Of Yttria-stabilized Zirconia Ceramic Material

Yttria-Stabilized Zirconia (YSZ) Ceramics is one of the important Oxide Ceramics. The structural ceramic components that manufactured by YSZ such as tools, dies, valves, bearings, engine liner, high-temperature refractories has excellent mechanical and physical properties; The multiple functions of ceramic components that manufactured by YSZ such as oxygen sensors, high-temperature solid oxide fuel cells, piezoelectric, ferroelectric ceramics has specific electrochemical properties. The thermal conductivity of YSZ ceramic material is important for its application in high temperature. Therfore, the thermal properties on of YSZ have been investigated in this work.YSZ ultrafine ceramic powder was prepared by chemical precipitation method. Ceramic biscuit was molded by dry molding method, and sintered in air at different temperature. The sintered ceramic body was characterized through XRD. The phase compositions were calculated. The microstructure of YSZ sintered at 1500℃for 0.5h⁶.5h were observed by SEM, and the grain size was measured. The density and porosity of the sintered samples were calculated. The thermal diffusivity of YSZ is measured by using laser pulse thermal conductivity system. The influences of Y₂O₃ content, porosity, phase composition and grain size on the thermal conductivity of YSZ were discussed. The result showed that the thermal diffusivity and thermal conductivity of YSZ decreased gradually with the increasing of Y₂O₃ content and porsity, but increased with the increase of grain size.