烧结温度对CuAlO2陶瓷电性能的影响

    Influence of Sintering Temperature on Electrical Properties of CuAlO2 Ceramics

    • 摘要: 为了提高CuAlO2陶瓷的电导率,满足其在热电器件使用中的要求,以Cu2O、Al2O3为原料,铝硅酸盐玻璃为添加剂,采用两步固相烧结法制备了CuAlO2(CAO)陶瓷,研究烧结温度对CAO陶瓷电导率的影响.实验发现:随着烧结温度的上升,CAO陶瓷的密度、晶粒尺寸和电导率逐渐增大.烧结温度为1 175℃时,CAO陶瓷的表观密度和相对密度达到最大值,分别为4.408 g/cm3和95.8%.当烧结温度达1 200℃时,CAO陶瓷晶粒生长发育完整,呈现多边形结构,且其电导率达到最大(2.42 S/m),比1 050℃的样品高了近10倍.阻抗谱分析表明,烧结温度对CAO陶瓷电导率的改善主要来自于晶粒阻抗的贡献.

       

      Abstract: To improve the conductivity of CuAlO2 ceramics, it is necessary to meet the requirements of thermoelectric devices. The delafossite CuAlO2(CAO) ceramics was made of Cu2O, Al2O3 and aluminosilicate glass powder with traditional solid sintering method. The influence of sintering temperature on the conductivity of CAO ceramics with aluminum silicate glass was studied. Results show that the density, grain size and electrical conductivity of CAO ceramics increase gradually with increasing sintering temperature. The apparent density and relative density of CAO ceramics reach maximum, 4.408 g/cm3 and 95.8%, respectively, when the sintering temperature is up to 1 175℃. When the sintering temperature comes up to 1 200℃, the grains of CAO ceramics develop fully and the shape of grains becomes polygon. The electrical conductivity reaches its maximum, 2.42 S/m, which increases by nearly 10 times as much compared with 1 050℃. The impedance spectrum analysis shows that with increasing sintering temperature, the improvement of the electrical conductivity of CAO ceramics is mainly due to the contribution of grain impedance.

       

    /

    返回文章
    返回