Morphology of copper corrosion and dissolution rate of copper in formic acid solution

Copper tubes were immersed in formic acid solutions ranging in concentration from 1 to 10000 mg/L for up to 84 days to investigate the effect of concentration of formic acid on copper corrosion. Concentrations of copper ion in test solutions were measured to determine the dissolution rate of copper. Concentrations of copper ion in formic acid solutions from 1 to 1000 mg/L were saturated in a certain value, while concentrations of copper ion in 5000 and 10000 mg/L formic acid solutions increase with an increase in immersion period. Corrosion form of copper tubes soaked in formic acid solutions from 1 to 1000 mg/L was an ant's nest corrosion, while the uniform attack occurred on copper tubes soaked in 5000 and 10000 mg/L formic acid solutions. Weight losses of specimens have a tendency to increase with increasing concentration of formic acid.