Supporting your Corrosion Prevention Control Plan with Compliant Computational Corrosion Analysis

Why bother with computational corrosion analysis? Apart from the obvious impact on safety, it has been shown that globally, corrosion costs about 4% of gross domestic product. Indeed, more recently the US Navy estimated that 40% of corrosion costs can be eliminated by better design. Considering that 70% of sustainment costs are already locked in by initial design then clearly, just as in thermal, fluid and stress analysis the use of upfront computational design tools for corrosion assessment has the potential to deliver huge value by helping us to avoid costly mistakes.

In DoD acquisition, Corrosion Prevention Control (CPC) planning is required by Title 10 U.S.C. 2366(b) and this is incorporated as DoD policy in the directive DODD 5000.01. The DoD Instruction DODI 5000.67: Prevention and Mitigation of Corrosion on DoD Military Equipment and infrastructure, outlines the process for setting up a CPC plan and calls out a number of standards such as MIL-STD-1568D and MIL-STD-889D to provide further, technical detail.

MIL-STD-1568D states that “Modeling and validation testing shall be performed to identify corrosion-prone locations”. Additionally, released August 2021, the new revision MIL-STD-889D Galvanic Compatibility of Electrically Conductive Materials (No longer ‘Dissimilar Materials’) actually introduces a paradigm shift, in that galvanic corrosion will no longer be estimated by the use of a table of electric potentials, but quantified by the calculation of galvanic current, based on a curated material database acquired using a consistent methodology defined in the specification.

We will introduce a workflow that incorporates a quick MIL-STD-889D-compliant analysis using the Corrosion Djinn® software. Full 3-dimensional, deeper dive analyses are then presented using the Siemens Teamcenter® and multi-physics software CCM+ combined with the Corrdesa electrochemical database to predict corrosion rate maps over 3D CAD components. This process will be demonstrated with examples of computational corrosion analysis on F/A-18 components.