Effect of Annealing on Mechanical Property and Formability of Cu/Al Clad Bipolar Plates in Proton Exchange Membrane Fuel Cells

The effect of annealing on the mechanical property in uniaxial tension tests and formability in micro coining processes of Cu/Al clad bipolar plates in proton exchange membrane fuel cells (PEMFC) is investigated. The results indicate both the thickness and the micro hardness of the interface layer increase with the increase of the holding time. The stress decreases firstly then increases with the increase of the holding time. The elongation decreases monotonically with the increase of the holding time. The micro coining of array micro channels results indicate that the height of micro rib increases with loading. The height of micro rib increases from the center to the edge along the transverse direction of the specimen. The simulation result by finite element method (FEM) verifies the experimental one.