MIL-STD-889D Compliance with Corrosion Djinn®

For the DoD and their suppliers, galvanic corrosion risk analysis has completely changed since the advent of the revised MIL-STD-889D. Designers must not use galvanic potential tables, they must now apply mixed potential theory, using material polarization data.

The problem

The revised standard, Figure 1, already 4 years old, provides a pre-calculated table of galvanic corrosion rates for common materials and coatings. However, many materials were not included and of course many new materials have since been introduced to the supply chain. This issue was foreseen, as the standard also outlines the protocol for acquiring further electrochemical data in a compliant manner.

MIL-STD-889D Document Image
Figure 1 – MIL-STD-889D Galvanic Corrosion Assessment

Compliant data acquisition services

Corrdesa established and led an industry/academic panel that, in the early days, shaped the protocol for the electrochemical data acquisition process that now forms Appendix B of MIL-STD-889D.

Consequently, Corrdesa has substantial experience and facilities, Figure 2, that enable acquisition and the essential post-processing of material polarization data in a MIL-STD-889D compliant manner, Figure 3. We have acquired data for many organizations to update and develop their corrosion mitigation design techniques.

Flat cell used to measure polarization data
Figure 2 – Flat cell used to measure polarization data
fitted polarization curve showing the partial reactions.
Figure 3 – Features of a fitted polarization curve

Management of electrochemical data

Corrosion Djinn® is not just a digital version of MILSTD-889D, but a commercial, fully functional software tool designed to significantly simplify the management and deployment of your electrochemical data, whether in the cloud or self installed at your own facilities. Corrdesa has developed a library of APIs to enable Djinn to communicate with other engineering design software. For example, at the push of a button, a user can export the data to Siemens NX-CAD, enabling a quick galvanic corrosion risk analysis and mitigation at the full 3D CAD level.

Additionally, data can be exported directly into a database integrated in Simcenter Star-CCM+, enabling full 3D Computational Corrosion Analysis. Corrosion Djinn® enables an enterprise to curate their electrochemical data, ensuring that downstream analysis processes reference a single point of truth.

The database structure enables definition of substrate and coating properties categorized for different environments, for example, the ASTM D1141 artificial seawater environment specified in MIL-STD-889D, or an ISO 9227 or ASTM B117 environment for comparison with chamber exposure tests. Information on relevant specifications and other properties can also be added.

Figure 4 – Djinn for electrochemical data management
Figure 5 – Corrosion Djinn Report

Galvanic corrosion rate calculations

Djinn, Figure 4-5, can very quickly execute the MILSTD-889D compliant “curve-crossing” galvanic corrosion calculations for your materials as well as many other materials already in the database. We may already have the material data you need, see www.corrosiondjinn.com

Materials
Coatings

Summary

If you require MIL-STD-889D compliant polarization data for materials not presently in the standard, then Corrdesa can help. The data could already be in our Database, or, if provided material samples, Corrdesa can acquire and post-process the electrochemical data in accordance with the standard and then deplo in Djinn for your use and consumption.