中文摘要：

本文探讨了采用离子半径较小的Sm~（3＋）代替La_（0.3）Sr_（0.7）Fe_（1-x）Cr_xO_（3-δ）中的La~（3＋）以降低这类阴极材料热膨胀系数的可行性。采用甘氨酸-硝酸盐法合成了Sm1-xSrxFe0.7Cr0.3O3-δ（x=0.5~0.7）粉体,在1350°C下烧结得到陶瓷样品。测试结果表明,陶瓷样品的相对密度均达到95%以上;在700°C下,陶瓷样品的电导率为~44 S×cm~（-1）;在40°C~1000°C温度范围内,陶瓷样品的平均热膨胀系数为12.8×10^-6K-1~14.1×10^-6K-1。

英文摘要：

The feasibility of replacing La~（3＋） in La_0.3Sr_（0.7）Fe_（1-x）Cr_xO（3-δ） by Sm~（3＋）to decrease the thermal expansion coefficients was studied. Sm1-xSrxFe0.7Cr0.3O3-δ（x = 0.5 ~ 0.7） powders were synthesized by using a glycine-nitrate process and the ceramic specimens were prepared by sintering at 1350°C. The results indicated that the ceramic specimens attained over 95% of their theoretical densities. The electrical conductivities of the specimens at 700°C were around 44 S×cm~（-1）. The thermal expansion coefficients of the specimens averaged over the temperature range of 40°C ~ 1000°C were in the range of 12.8 × 10~（-6）K~（-1） ~ 14.1 × 10~（-6）K~（-1）.