High-temperature mechanical and thermal properties of Ca1-xSrxZrO3 solid solutions

Perovskite oxides are promising thermal barrier coatings (TBCs) materials but their thermophysical properties still need to be further improved before commercial applications. In this work, mechanical/thermal properties of calcium-strontium zirconate solid solutions (Ca1-xSrxZrO3) are investigated. Comparing to the end-compounds CaZrO3 and SrZrO3, the solid solutions achieve the enhanced thermal expansion coefficient, decreased thermal conductivity as well as good high-temperature mechanical properties. The experimental thermal conductivities of Ca1-xSrxZrO3 (x = 0.2, 0.4, 0.6, 0.8) are in the range of 1.76-1.94 W center dot(m center dot K)(-1) at 1073 K, being lower than that of the yttria-stabilized zirconia (YSZ). At the same time, their thermal expansion coefficients (10.75 x 10(-6)-11.23 x 10(-6)/K at 1473 K) are comparable to that of YSZ. Moreover, the Young's moduli of Ca0.8Sr0.2ZrO3, Ca0.6Sr0.4ZrO3, Ca0.4Sr0.6ZrO3, and Ca0.2Sr0.8ZrO3 at 1473 K are 70.7%, 69.4%, 68.8%, and 71.1% of the corresponding values at room temperature, respectively. The good high-temperature mechanical and thermal properties ensure the potential applications of Ca1-xSrxZrO3 solid solutions as high-temperature thermal insulation materials including TBCs.