Consideration of Corrosion Behavior of Aluminum Wire at Crimped Terminal and Effective Anti-Corrosion Treatment

The demand for weight reduction of vehicles is growing in compliance with CO₂ emission control requirements. Also, demand for copper is on the rise with an increase in the number of electric vehicles because their motors and wiring require a lot of copper. This has raised concerns about higher copper prices and vehicle weight. Recently, attempts to reduce vehicle weight have been actively made by partially replacing copper with aluminum, which is lighter and less expensive. Although the use of aluminum wires on limited areas of some vehicles has already been reported, that on all areas has not been reported yet. The authors focus on reducing weight of wiring harnesses, which is about 20 kg per vehicle, and consider using aluminum instead of copper as the conductor of the electrical wires. One of the factors impeding the use of aluminum wires in wider areas is galvanic corrosion occurring at crimped terminals. Since aluminum causes galvanic corrosion when the metal is in electrical contact with a different metal in an electrolyte, it is essential to prevent this phenomenon from occurring at crimped terminals in mounting aluminum wires on vehicles. An anti-corrosion treatment needs to effectively prevent the occurrence of corrosion at the locations where aluminum wires are used. To devise an appropriate anti-corrosion treatment, it is necessary to grasp how aluminum wires corrode at the crimped terminals. This paper describes findings from a study of corrosion behavior of aluminum wires at crimped terminals for the purpose of developing an effective anti-corrosion treatment to increase the area onto which aluminum wires can be used.