A novel strategy for improving the performance of automotive cylinder-head gaskets using a multilayer severe plastic deformation method

Cylinder head gaskets, as critical components in internal combustion engines, require a balanced combination of high mechanical strength, adequate thermal conductivity, and long-term corrosion resistance. Conventional metallic gaskets (e.g., copper-based), despite their high strength and thermal conductivity, suffer from limited corrosion resistance, whereas polymeric or composite gaskets exhibit improved corrosion resistance but are restricted by lower mechanical strength and thermal conductivity. In this study, a copper/graphene nanocomposite was fabricated via four consecutive cycles of accumulative roll bonding (ARB) at room temperature under dry rolling conditions. The corrosion behavior of the samples was evaluated using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization tests in a ۳.۵ wt.% NaCl solution. The results revealed that the ARB process alone reduced the corrosion resistance of copper, as evidenced by an increase in corrosion current density in the graphene-free sample. In contrast, the incorporation of reduced graphene oxide at an optimal content of ۱ wt.% significantly enhanced the corrosion resistance, leading to an approximately ۸۰% reduction in corrosion current density and more than a ۳.۵-fold increase in polarization resistance. For samples containing ۲ wt.% graphene, corrosion stability deteriorated due to microstructural inhomogeneity and localized graphene agglomeration. Overall, the combined application of electrostatic deposition of reduced graphene oxide and accumulative roll bonding is demonstrated to be an effective approach for producing multilayer Cu/graphene nanocomposites with improved anticorrosion performance, with ~۱ wt.% graphene identified as the optimal composition for copper-based components operating in chloride-containing environments such as automotive engines.

کلیدواژه ها:

Cu/graphene Composite ، Accumulative Roll Bonding (ARB) ، Corrosion Resistance ، Electrostatic Coating ، Automotive Cylinder-head Gasket