effect of coating on the corrosion of carbon steel in variable mediums by using coating multi walled carbon nanotube and antibacterial activity

The corrosion rates of carbon steel in three variable solution mediums (sulfuric acid, acetic acid, and seawater) are estimated by using six samples of mild steel with and without coating after periods (10, 20 and 30 days). the type of coating used is multi-carbon nanotube material with a thickness of 300 nm. in general, for two cases with and without coating the carbon steel, the values of the corrosion rates of the carbon steel in all three mediums decrease with immersion time. also, it was concluded that the magnitudes of the corrosion rates in sulfuric medium are greater than those of other mediums (acetic acid and seawater). a low value of the corrosion rates of the seawater medium can be selected; this is due to the fact that the ability of acids to corrode metal is greater than that of salt. the effect of metal coating on the corrosion rates is low when the metal samples are submerged in sulfuric acid medium, but a high decrease in corrosion rates due to the metal coating can be noted when the metal samples are immersed in acetic acid medium. compared to carbon steel, the carbon steel coated with a multiwalled carbon composite exhibited enhanced antibacterial activity, with a zone of inhibition of 14 mm against escherichia coli. the carbon steel coated with a multiwalled carbon composite showed good corrosion resistance. the corrosion resistance of the resultant coating was studied by electrochemical analysis.