In this work, we investigated the influence of bolt geometry on the bimetallic corrosion of galvanized steel bolts and low carbon steel plate (in joint/couple state) in acidic (pH \(4\) ) and alkaline (pH \(9.2\) ) electrolyte solution. The potential and current density distributions as well as metal thickness loss across square, hexagonal, and round bolts with pitch circle diameter (PCD) \(70\text{ mm}\) , \(80\text{ mm}\) , and \(90\text{ mm}\) are simulated using 3D finite element model in COMSOL multiphysics. We have also performed complimentary non-destructive experiments for estimating the metal thickness loss to validate our simulations. It is found that the round shape bolt with PCD \(70\text{ mm}\) positioned with LCS plate exhibits the lowest metal loss in both environments, thus corroborating with the catchment area principle and highlighting the importance of bolt geometry in mitigating the galvanic corrosion. Our simulations are in close agreement with experimental results (i.e., error \(<\pm 10\text{\%}\) ), thereby confirming the validity of the model. Our work opens ample avenues of bridging multiphysics computation framework with experiments to alleviate galvanic corrosion problem in bolted assemblies of automobile parts further demonstrating the utility of advanced non-destructive techniques for model validation.
