Aluminum Clad Ferritic Stainless Steel Foil for Metallic Catalytic Converter Substrate Applications
A roll bonding process was developed to produce Al clad ferritic stainless steel foil for the metallic catalytic converter substrate application. Clad foils with different chemistry were produced and their properties were evaluated. Heat treatment conditions for the homogenization of clad foils were identified. This article includes results from oxidation tests and mechanical tests on as-rolled and heat treated clad foil. Results from commercial ingot metallurgy foil were also included for comparison. The oxidation weight gain study indicates that the Al content in the foils is directly related to the usable life of the foil. However, rare earth addition is necessary to improve the oxidation resistance of this material for the high temperature applications by slowing down the weight gain kinetics and thus extend the usable life of foils. The heat treated clad foil also exhibit excellent tensile ductility when compared to the ingot metallurgy foil.