Ca1-xBaxZr4(PO4)6磷酸盐陶瓷材料的热膨胀特性

Ca1-xBaxZr4(PO4)6(0≤X≤1.0)属于NZP族磷酸盐陶瓷材料，它是新的一类低热膨胀陶瓷材料。研究发现CaZr(PO4)6(X=0)及BaZr4(PO4)6(X＝1)时的轴膨胀特性正好相反，因此当X为某一值时热膨胀系数将为零。本研究采用共沉淀法合成了Ca1-xBaxZr4(PO4)6磷酸盐陶瓷材料，当X＝0时，热膨胀系数为－0．86×10-61／℃；当X＝0．25时热膨胀系数为2．7×10-61／℃；当X＝0．75时其热膨胀异向性最小。为了得到热膨胀异向性和热膨胀系数均小的Ca1-xBaxZr4(PO4)6磷酸盐陶瓷材料，X应在0．6至0．9之间，并通过控制烧结条件抑制晶粒的生长。

Thermal Expansion Properties of Ca1-xBaxZr4(PO4)6 Phosphate Ceramic Materials

Ca1-xBaxZr4(PO4)6(0≤X≤1. 0)system which belongs to a new large family of low thermal expansion materials know as NZP. It was found that CaZr4 (PO4)6(X＝0) and BaZr4(PO4)6 (X= 1) had opposite anisotropies in their respective axial thermal expansion,therefore,the near-zero thermal expansion can be obtained by selecting X value. Ca1-xBaxZr4 (PO4)6 was synthesized by the coprecipitation method. When X ＝0 and X = 0.25 ,the bulk thermal expansion coefficient was－0. 86×10-61/℃ and 2.7×10-6/℃ respectively. When X= 0. 75 ,the thermal expansion anisotropy is much smaller than any others. In order to getting low thermal expansion anisotropy and low bulk thermal expansion coefficient for Ca1-xBaxZr4 (PO4)6 phosphate ceramic materials ,X should be between 0.6 and 0.9 ,and must reduce the growth of grains by control ling sinter conditions.