GRADED METAL HARDWARE COMPONENT FOR AN ELECTROCHEMICAL CELL

摘要

A graded metal hardware component for an electrochemical cell is shown for mechanically supporting electrochemical cell structures and defining fluid cavities and fluid passages in a cell employing a solid polymer electrolyte membrane. The graded metal hardware component includes a substrate such as stainless steel, a surface layer made of a precious metal such as gold, and a graded boundary layer adjacent to and between the substrate and surface layer, wherein the graded boundary layer is an interdiffusion of the substrate and surface layer so that the graded boundary layer is between 0.5 wt.%-5.0 wt.% of the material making up the substrate, and between 99.5 wt.%-95.0 wt.% of the material making up the surface layer, and the graded boundary layer has a thickness of between 10 %-90 % of a shortest distance between the substrate and an exterior surface of the surface layer. In a preferred embodiment a shortest distance between the substrate and an exterior surface of the surface layer is between 50 to 120 microinches, and the exterior surface of the surface layer has a hardness of between 150 to 200 on the Knopp scale. A preferred method of manufacturing the graded metal hardware component includes the steps of first applying a coating of acid gold to the substrate, then applying a hard gold coating to the once coated substrate to form the surface layer, and finally heat treating the twice coated substrate to between 200 degrees Celsius (" DEG C") to 500 DEG C for between 1 to 24 hours to form the graded boundary layer.