Surface Defects and Corrosions Developed on Copper Clad Aluminium Wires Investigated by Scanning Electron Microscope Analysis and X-Ray Mappings
Copper-clad aluminium (CCA) is a bi-metal electrical conductor consisting of an outer sleeve of copper that is metallurgically bonded to a solid aluminium core. In the market, CCA has started to replace copper wire for several decades because of its low cost and light weight. The demand for CCA wire has increased parallel to industrial and technological development in many sectors over the last decades. The structural surface defects and corrosion affect the quality of CCA wires. Corrosion deterioration can be detected visually and chemically; hence it was subjected to imaging and microchemical mapping. Textural defects such as significant abrasion grooves, tensional cracks, delamination of copper, pit corrosion, fatigue failure have been found. Silicon Drift Detector-Electron Dispersive Spectrometer-Scanning Electron Microscope (SDD-EDS-SEM) X-Ray mappings and chemical analysis exhibit that the corrosion has happened along with the textural defects. The oxidation is widely observed, and some electrolyte-related chemicals have been detected as deposited substances. The corrosion types have also been classified as galvanic corrosion, pitting corrosion. It is recommended to inspect the products with SEM studies before or during trade, as structural defects formed during manufacturing facilitate corrosion.