Correlation between oxygen vacancy and mechanical properties in oxideunder chemical potential

固体氧化物燃料电池(SOFC)要实现商业化，除了电气可靠性外，还必须保证SOFC的机械可靠性。因此，建立一种适用于各种温度和氧分压条件下的力学测试方法是开发可靠的SOFC的前提。本文介绍了SOFC组件在还原条件下的弹性模量和断裂强度的实验研究结果。为了研究固体氧化物燃料电池组件在高氧化/还原环境下的弹性模量和断裂强度，提出了一种原位力学测试方法。弹性模量在还原条件下发生变化，这种行为很可能是由于非化学计量比造成的。结果表明，现场力学测试方法能够估计SOFC电池单元和电堆的内应力。

For the commercialization of solid oxide fuel cell (SOFC), in addition to the electrical reliability, it is also important to ensure the mechanical reliability of SOFC. Thus, the establishment of a suitable mechanical testing method under various temperatures and oxygen partial pressure conditions is a prerequisite for the development of reliable SOFCs. This paper presents the experimental results of the investigation of elastic modulus and fracture strength on the SOFC components under reducing conditions. An in-situ mechanical testing method was developed in order to investigate the elastic modulus and fracture strength of solid oxide fuel cells components under high oxidizing/reducing environments. The elastic modulus was shown to change under reducing condition, and the behavior was most likely due to non-stoichiometry. It was demonstrated that the in-situ mechanical testing method enabled us to estimate the internal stress in the SOFC cell and stack.