Galvanic Corrosion of Automotive Mixed Metal Substrates: Fundamental Understanding
Abstract
Dissimilar metal joining is of increasing interest in many structural applications due to its potential to enable light weighting. Light-weight substrates such as aluminum alloys, magnesium alloys and carbon-fiber reinforced polymer (CFRP) are increasingly used in place of conventional steels due to their high strength-to-weight ratios. Two of the main challenges associated with the increased usage of mixed metal systems are galvanic corrosion and challenges with classical joining methods. 1,2. Most joining methods such as riveting, mechanical fasteners, and welding, results in electrical connection between the joined metals, which poses galvanic corrosion issues. Even galvanic isolation approaches such as the use of adhesives can cause galvanic corrosion problems due to the complexity of mixed metal assemblies. In galvanic coupling scenarios, the less noble material experiences severe corrosion and more noble material is protected. It is important to build a fundamental understanding of this phenomenon relative to the metallurgy and electrochemistry of the substrates, as well as the coupling method, to provide effective corrosion mitigation solutions.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Sep 01, 2019
- Source ID
- 10.1149/ma2019-02/9/785
Entities
People
- Balaji Kannan
- Marvin Pollum
- Mary Lyn Lim
- Richard Fleischauer
- Susanna Fraley