Abstract

A strength design method was developed to form channels using ultrathin stainless steel foil in the structural design of metallic separators for a fuel cell. This method focused on the work hardening characteristic of stainless steel, and defined the deformation behavior of the metallic foil as a function of the strain value, based on the strength-related physical property values of the metallic materials. The shape range that can be formed with metallic foil was obtained using a forming limit diagram and localized strain values calculated from measurements of the material physical property values. In addition, the mechanical stress produced on the metallic separators of the fuel cell during fuel cell stack power generation was obtained from localized strain values calculated by micro Vickers hardness measurements. The metallic foil life with respect to mechanical degradation could be evaluated by plotting this stress value in the material fatigue limit diagram.

References

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Author (organization or company)

• Katsunori SAIKI（Automobile R&D Center）

Publication Information

Article of Honda R&D Technical Review Vol.29 No.1 (197 - 204)

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