Effects of cerium addition on the microstructure, mechanical properties and thermal conductivity of YSZ fibers

Ce-doped yttria-stabilized ZrO 2 (YSZ) fibers were prepared with different Ce concentrations (0, 5, 10, 20   mol%) by the sol-gel method. The effects of Ce addition on the microstructure and mechanical properties of the YSZ fibers have been investigated. Compared with the pure YSZ fibers, the Ce addition could cause grain refinement whose mechanism was discussed. Moreover, mechanical measurements showed that the Ce addition could increase the Young's modulus and microhardness of the YSZ fibers. When the doping content was 10%, the values of Young's modulus and microhardness were improved by almost 3 times and 2 times compared with those of the pure YSZ fibers, respectively. Results show that the Ce addition could improve the thermal insulation , thermal conductivity at 800   °C being reduced by over one third (33.52%) when the amount of Ce increased to 20%.