通过在YBa2Cu3O7-δ的起始原料中直接掺入过量的BaO和等摩尔ZrO2,原位生成均匀弥散分布的BaZrO3第二相颗粒的方法制备YBa2Cu3O7-δ-BaZrO3复合混合导体材料。研究了引入第二相BaZrO3颗粒对基相YBa2Cu3O7-δ的微观结构、热膨胀行为和力学性能的影响。发现弥散的BaZrO3颗粒能有效地抑制YBa2Cu3O7-δ沿C轴方向的生长,使晶粒由条形变为方形。与YBa2Cu3O7-δ单相样品相比,含10 mol%Ba-ZrO3颗粒的样品具有更高的相对密度和较低的热膨胀系数以及显著改善的力学强度。
YBa2Cu3O7-δ-BaZrO3 composites were prepared by solid state reaction with in situ producing the dispersed BaZrO3 secondary phase particles via addition of ZrO2 and iso-molar excess BaO in starting materials. The effects of inclusion of BaZrO3 particulate phase on the microstructure, thermal expansion behavior and mechanical strength of YBa2Cu3O7-δ has been investigated. It is found that BaZrO3 phase can effectively suppress the grain growth of YBa2Cu3O7-δ phase in the c-axis direction, leading to change of grains from bar-like to cubic-like. The sample containing 10 mol % of BaZrO3 exhibits higher relative density and relatively thermal expansion coefficience and much improved mechanical strength, compared with the sample without containing the second phase.