GLOBAL ENGINEERING RESEARCH AND TECHNOLOGIES, LLC — Department of Defense STTR Phase I: N22A-T003

Description

Corrosion damage to NAVAIR aircraft fleet remains a major challenge with implications for both the safety of DOD personnel and equipment, as well as for an efficient operation of components and structures. This damage is mainly due to corrosion fatigue and/or stress corrosion cracking. Mitigation of this problem is often done through the electrodeposition of a corrosion resistant coating such as Nickel-Zinc or the more environmentally harmful Cadmium. Factors such as surface roughness, coating thickness/uniformity, porosities/microcracking, residual stresses along with pre- and post-treatment are extremely critical for an effective and durable coating as well as fatigue life. A new computational framework that will enable a two-way coupling between the corrosion damage and mechanical stresses (internal/residual and externally applied) is proposed for capturing the synergistic effects of mechanical loading and corrosion on the material integrity of electroplated parts. The proposed methodology, based on a new theory called peridynamics (PD), overcomes singularities that are the source of failure of existing computational models. In Phase I, we will apply the PD theory to develop the growth model for simulating electroplating process and fatigue life prediction of electroplated parts in the presence of residual stress and corrosion as well as a qualification testing plan for validation. The PD - based simulation iterates with a mechanical solver that can predict interacting cracks, defects, and possible delamination of electroplated samples under combined mechanical and thermal loads.  In Phase II, focus will be on the interactions between mechanical fatigue and corrosion in predicting fatigue strength in electroplated samples in ANSYS framework as well as further testing for validation of simulations. The final product of this project will be a prototype software for life prediction simulation of electroplated parts under complex loading condition and harsh environment, along with a comprehensive manual