Effects of direct current electric field on corrosion behaviour of copper,Cl- ion migration behaviour and dendrites growth under thin electrolyte layer
(1. School of Chemical Engineering and Pharmacy, Wuhan Institute of Technology, Wuhan 430073, China;
2. School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology,
Wuhan 430074, China)
2. School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology,
Wuhan 430074, China)
Abstract: Effect of direct current electric field (DCEF) on corrosion behaviour of copper printed circuit board (PCB-Cu), Cl- ion migration behaviour, dendrites growth under thin electrolyte layer was investigated using potentiodynamic polarization and scanning electron microscopy (SEM) with energy dispersive spectrometer (EDS). Results indicate that DCEF decreases the corrosion of PCB-Cu; Cl- ions directionally migrate from the negative pole to the positive pole, and enrich on the surface of the positive pole, which causes serious localized corrosion; dendrites grow on the surface of the negative pole, and the rate and scale of dendrite growth become faster and greater with the increase of external voltage and exposure time, respectively.
Key words: copper; dendrites; migration; direct current electric field; thin electrolyte layer; copper printed circuit board