An Effective Anti-Discoloration Coating for Copper

Abstract

This article investigated the effectiveness of a newly developed anti-discoloration method for copper (C1100). The procedure involved diffusion of aluminum into the copper substrate and the subsequent formation of Cu-Al oxide spinels on the surface by a heat treatment. Samples of C1100 with and without surface treatment were subjected to ageing at 250°C for various length of time up to 40 min in order to promote surface discoloration due to oxidation. In addition, a commercially available anti-discoloration coating (C-107) was applied on testpieces for comparative studies. Tested samples were subjected to spectral colorimeter studies in order to determine the degree of discoloration occurred on the surface; microstructures and phase identifications were examined by SEM and XRD. In conclusions, the newly developed method exhibited potential to protect the surface of C1100, and its performance surpassed that of C-107.