INHIBITING ACTION OF N-NAPTHYL–N L - PHENYL THIOUREA ON THE CORROSION OF 304 SS IN HCL MEDIUM

304 SS is a highly prominent material that is commonly used in industries. Since, it is highly susceptible to corrosion, predominantly in aqueous medium; the study on the corrosion behaviour of 304 SS is the need of an hour for improving the quality and reliability of products and services. It is well-known that corrosion inhibition is one of the mechanisms used in the manufacturing sectors for mitigating the corrosion of metals and alloys. Hence, the present work aims to study the inhibiting effect of Nnapthyl–N l -phenyl thiourea (NPTU) on the corrosion of 304 SS in 1M HCl using Tafel extrapolation and impedance spectroscopy methods. The study reveals that the compound investigated acts as a mixed inhibitor for steel corrosion in hydrochloric acid medium and gives a sensibly good inhibition efficiency (>77%). The study also reveals that the compound NPTU inhibits the corrosion of 304 SS through adsorption and film formation mechanism. The mechanism of adsorption of the compound follows Temkin's isotherm model and the inhibition is governed by physical adsorption along with a weak chemical bonding