Crack Growth Behavior in Metal-elastomer Bonding Interface under Cyclic Deformation

Introduction: Metal-elastomer adhesion becomes increasingly important for elastomer parts comprising metal components, such as packer elements for Blowout Preventers (BOP), completion packers, metal encapsulated seals, and stator/rotors. As the bonding between metal and elastomer deteriorates under cyclic deformation, cracks can appear on the adhesion interface and reduce the function of the parts. Methods: Thus, the fatigue performance or crack growth rate of the metal-elastomer adhesion affects the service life of the whole elastomer part. In this study, the metal-elastomer bonded parts were fabricated and evaluated under cyclic shear and peel deformation at both room temperature and high temperature. Results: The crack growth rates (dc/dN) on the metal-elastomer interface were measured based on the strain energy release rate (Gc) for different elastomers with both excellent and poor adhesion, and the API lifetime of BOP packers were therefore estimated. Conclusion: The results indicated that the crack growth rates in the adhesion interface can be correlated with the API lifetime of BOP packers, and the elastomer with a low crack growth rate will have a better fatigue life for the BOP application.