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摘要: 采用柠檬酸溶胶凝胶和放电等离子烧结制备了Ca位双掺杂型的BaxAgyCa3-x-yCo4O9烧结体，利用X射线衍射仪、扫描电子显微镜、电阻率测试仪等研究了烧结体相组成、取向度、织构及电性能.结果表明：含Ag的掺杂试样中出现了偏离化学计量比分布的Ag单质，掺杂试样取向度随Ba与Ag掺杂量之比x/y的增大而提高，含Ag的掺杂试样取向度低于未掺杂试样，不含Ag的掺杂试样取向度高于未掺杂试样.x=y=01的试样导电机理发生变化.Ba，Ag掺杂量相等的试样保持较低取向度的同时具有较低的电阻率，在973 K时达到最低值（73 mΩcm），而取向度最低的Ag单掺杂试样电阻率在所有试样中最低，在973 K时为63 mΩcm.
Abstract: Doublesubstituted BaxAgyCa3-x-yCo4O9 bulks were fabricated by nitric acid solgel and spark plasma sintering, and the phase composition, orientation, texture and electrical transport properties of the bulks were investigated by means of X-ray diffraction,scanning electron microscope and electrical resisitivity measurement. The result shows that silver which does not belong to the stoichiometric compounds BaxAgyCa28Co4O9 is distributed in the matrix. The degree of orientation increases with increasing ratio of Ba to Ag for the doublesubstituted bulk. The orientation of BaxAgyCa28Co4O9 （y>0） bulks is prominently lower than that of Ca3Co4O9 and the orientation of Ba02Ca28Co4O9 bulk is higher than that of Ca3Co4O9 bulk. The electrical transport mechanism of the bulk with x=y=01 is changed slightly. The Ba01Ag01Ca28Co4O9 bulk exhibits simultaneously lowered orientation and moderately low resistivity and the resistivity reaches 73 mΩ·cm at 973 K. The Ag02Ca28Co4O9 bulk exhibits lowest orientation and lowest resistivity, reaching 63 mΩ·cm at 973 K.
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