Consideration of Corrosion Behavior of Aluminum Wire at Crimped Terminal and Effective Anti-corrosion Treatment 2019-01-0486
The demand for weight reduction of vehicles is growing to comply with CO2 emission control. Also, demand for copper is on a rise with an increase in the number of electric vehicles because their motors and wiring require a lot of copper. That causes a higher copper price and vehicle weight. To reduce vehicle weight, aluminum, which is lighter and less expensive than copper, has been more commonly used instead of copper in recent years. We 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. Although mounting of aluminum wires on limited areas of some vehicles has already been reported, mounting of those on all areas has not been reported yet. One of the factors impeding use of aluminum wires in wider areas is galvanic corrosion caused at crimped terminals. Since aluminum causes galvanic corrosion when it 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. However, excessive anti-corrosion treatment will decrease the benefits gained from using aluminum wires because of an increase in treatment cost. To increase the area on which aluminum electric wires are mounted, we believe that it is necessary to balance performance with treatment cost in consideration of mounting area. This paper describes our efforts in studying corrosion behavior of aluminum wires at crimped terminals to develop an effective anti-corrosion treatment.