Formation of Protective Oxide Scale with High Electrical Conductivity by High Temperature Oxidation of Alloys.

用(La，Sr)CoO_3包覆的Cr_2O_3合金高温氧化，成功地获得了高导电性的Cr_2O_3氧化膜。对氧化膜的微观结构分析表明，氧化膜中析出了锶铬氧化物，析出物之间可能是相互联系的。这些氧化物是：SrCrO_4、Sr_3CR_2O_8、Sr_3CR_2O_7、Sr_2CrO_4。这些氧化物的电导率远大于Cr_2O_3。为了估算这些氧化物在氧化膜中的分布，绘制了锶-铬-氧体系的相图，并测定了这些氧化物的标准吉布斯生成能。这些结果对固体氧化物燃料电池中合金隔膜的设计具有一定的指导意义。

The highly conductive Cr_2O_3 scale was successfully obtained by high temperature oxidation of Cr_2O_3 formig alloys coated with (La, Sr) CoO_3. Microstructural analysis on the scale found that the Sr-Cr-Oxides precipitated in the scale and that the precipitates probably connected each other. The oxides are SrCrO_4, Sr_3Cr_2O_8, Sr_3Cr_2O_7, Sr_2CrO_4. The electrical conductivity of thses oxides were much larger than that of Cr_2O_3. To estimate the distribution of these oxides in the scale, the phase diagram in Sr-Cr-O system was constructed and the standard Gibbs energy of formation of these oxides weredetermined. These results are applicable to the design of the alloy separator in solid oxide fuel cell.