Studying The Effect of Copper And Zinc Ions on The Corrosion Rate of Carbon Steel

Abstract

An experimental work was performed to study the effect of Zn, Cu ions onthe corrosion rate of carbon steel in distilled and tap water solution containing, 25& 50 ppm concentration of Zn, Cu ions at pH range 4, 6 &8 in distilled water andat pH8 in tap water at room temperature under both static for 10 weeks and 1, 2,6 &12 hours with dynamic conditions. The obtained results showed that thecorrosion rate was increased in the presence of 50 ppm of Cu ions in tap water(2.326 mpy) after 10 weeks, under static conditions, whereas under dynamicconditions, it was reached (10.511 mpy), the presence of fine suspended solidparticles in the solutions may also cause an increase in corrosion rate due to theirmovement over the carbon steel surface .In contrast, the presence Zn ions insolution as sacrificial anode, therefore, the corrosion rate was 2.24 times less thanthat in presence of Cu ions, at the same conditions. In distilled water, thecorrosion rates were decreasing slightly with adding Zinc and copper ionscomparing to absence of metals ions in solution except at pH4 in the presence50ppm of Cu ions may be accounted due to the increasing in the conductivity ofthe solution, under static conditions. At 25ppm of Zn ions lowering in corrosionrate may be explained that the Zn ions were protected carbon steel surface bysacrificial. In the absence of Zn, Cu ions were also carried out.