Surface characterization and corrosion behavior of a novel gold-imitation copper alloy with high tarnish resistance in salt spray environment

• A novel imitation-gold copper alloy (CuZnAlNiSnBRe) was designed.
• The new alloy has good tarnish resistance and corrosion resistance performance.
• A multi-layer corrosion film formed on the surface of the new alloy.
• The corrosion products was a mixture of CuO, Cu2O, ZnO, Al2O3 and Al(OH)3.
• A transition of the product from Cu2O to CuO occurred during the corrosion process.

A novel gold-imitation copper alloy (CuZnAlNiSnBRe) was designed and its corrosion behavior in salt spray environment was investigated. The new alloy has better tarnish resistance and corrosion resistance than the current coinage alloy used in China (H7211). A multi-layer film formed on the surface of the new alloy after a period of exposure to salt spray was responsible for the good resistance of the alloy. The corrosion products were a mixture of CuO, Cu2O, ZnO, Al2O3 and Al(OH)3, with the transition from Cu2O to CuO occurring during the corrosion process.