Investigating the mechanism behind 'ant nest' corrosion on copper tube

Abstract

A research investigation of "ant nest" corrosion (ANC) on copper tube was conducted in terms of the variables of the corrosion potential and pH value in 103 ppm copper formate solution over 20 days. The paper presents the surface and cross-sectional observations and examines Cu2O and H2O as the stable chemical species produced. A Cannizzaro reaction as a disproportionation reaction from formic acid and a comproportionation reaction from the metallic copper tube and copper formate solution critically influenced the ANC mechanism. The paper also categorizes the ANC attack as a rapid reaction system from the electrochemical point of view by using a polarization resistance curve.