燃料电池金属气体扩散层结构的力学行为建模及成形成性工艺

项目名称： 燃料电池金属气体扩散层结构的力学行为建模及成形成性工艺

项目编号： No.51305262

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 机械、仪表工业

项目作者： 易培云

作者单位： 上海交通大学

项目金额： 26万元

中文摘要： 传统板框式燃料电池结构中，双极板约占电堆总重量的80%、总体积的60%，制约了电堆功率密度的提高。无极板式燃料电池结构采用波浪型金属气体扩散层兼顾传统意义上的双极板和气体扩散层功能，可将功率密度提一倍以上。然而，波浪型金属气体扩散层成形过程中容易产生纤维断裂和孔隙畸变等缺陷，主要原因是现有的针对连续介质的成形工艺设计理论不能很好的适用。本项目引入细观力学理论和统计学方法，建立金属纤维多孔材料弹塑性本构模型以及考虑纤维断裂和孔隙畸变的失效准则，形成金属纤维多孔材料力学行为建模方法；在此基础上，建立波浪型金属气体扩散层结构成形工艺仿真模型，揭示材料、模具和工艺参数对成形精度和微观性能的影响规律，形成波浪型金属气体扩散层成形成性工艺设计方法；构建金属气体扩散层成形实验原型系统，制备高精度高性能的波浪型金属气体扩散层部件，进而建立无极板式燃料电池实验原型，为新型无极板式燃料电池的应用提供基础。

中文关键词： 力学行为建模；微细成形；仿真分析；金属纤维；燃料电池

英文摘要： For a conventional proton exchange membrane fuel(PEMFC) in plate-and-frame architecture, bipolar plates account for approximate 80% of the stack weight and 60% of the stack volume which restrict the improvement of stack power density. A novel plateless PEMFC architecture, in which the wave-like metallic gas diffusion layer (MGDL) is adopted to give consideration to the function of traditional bipolar plate and GDL, is proposed and the power density is expected to be double. Nevertheless, defects such as fiber breakage and pore distortion are easy to occur in the forming process of wave-like MGDL. The root cause is that the current forming process design theory based on continuous media is not well applicable. In this study, a elastoplastic constitutive model of MGDL and a failure criteria considering the fiber breakage and pore distortion are firstly established based on the theory of micromechanics and statistical method. The modeling method for mechanical behavior of MGDL is thus developed. On this basis, a simulation model for the forming process of wave-like MGDL is then developed to reveal the influence of material, mold and process parameters on forming precision and micro-properties. Thereby, the process design method is achieved integrating the forming and performing performance. Finally, an experiment

英文关键词： Mechanical behavior modeling；Micro forming；FEM analysis；Metal fiber felt；PEM fuel cell