Corrosion behavior and performance degradation of aluminum-copper cable joints with magnetic pulse crimping in salt spray environment
(1. State Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle, Hunan University, Changsha 410082, China;
2. Shenzhen Automotive Research Institute, Beijing Institute of Technology, Shenzhen 518118, China;
3. The First Product Department, FinDreoms Battery Co., Ltd., Huizhou 516083, China;)
2. Shenzhen Automotive Research Institute, Beijing Institute of Technology, Shenzhen 518118, China;
3. The First Product Department, FinDreoms Battery Co., Ltd., Huizhou 516083, China;)
Abstract: The corrosion resistance of aluminum (Al) cable-copper (Cu) terminal joints fabricated by magnetic pulse crimping (MPC) and hydraulic clamp crimping (HCC) was compared. Performance degradation was evaluated by mechanical and electrical properties. Additionally, corrosion behavior was analyzed by electrochemical testing. Microscopic characterization was performed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Results show that the tensile strength of the corroded joints is reduced. However, due to the advantages of high-speed forming and contact tightness unique to MPC, the contact resistance of the corroded joints still maintains excellent. Electrochemical tests demonstrate that the MPC joints have higher corrosion potentials and smaller corrosion currents, providing better corrosion resistance. The formation of a primary battery between Al and Cu at the lap joint leads to the formation of severer corrosion pits.
Key words: magnetic pulse crimping; aluminum-copper cable joint; salt spray corrosion; performance degradation; corrosion mechanism