In order to reduce the thermal stress of solid oxide fuel cell in the process of preparation and working,and improve the electrochemical performance of the cell,the functionally graded layer is introduced into the cell.Due to the property of the functionally gradient material changes continuously or stepwise in a certain direction,the layer can reduce the difference of material parameters and relieve the thermal mismatch stress between layers effectively.On the basis of the previous research and the idea of hierarchical method,the anode functional layer is introduced into the solid oxide fuel cell,and the material parameters of the sub-layers are controlled through the anode functional layer number and the nonlinear gradient component exponent n.Thermal stress of the solid oxide fuel cell is studied at 800℃ within the operating temperature.The results show that the maximum tensile stress of the anode layer and the maximum compressive stress of the electrolyte layer decreases by introducing the anode functional layer.With the same anode functional layer number,the maximum tensile stress increases with the exponent n,and the maximum compressive stress of the electrolyte layer decreases with the exponent n increase.The thermal stress may lead to cracks and destroy the solid oxide fuel cell structure.This research provides theoretical basis for design and optimization of the solid oxide fuel cell.%为了降低固体氧化物燃料电池在制备和工作过程中产生的热应力,提高电池的电化学性能,在电池中引入功能梯度层可以有效减小电池各层之间材料参数的差异,从而缓解各层之间的热失配应力.本研究将阳极功能层引入燃料电池中,通过阳极功能层子层数目和非线性梯度成分指数n控制各子层材料属性的变化情况,研究了燃料电池在800℃下的热应力分布.结果表明:选取适当的指数n和阳极功能层的分层数目可以明显降低阳极层的最大拉应力和电解质层的最大压应力.
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