CORROSION OF MATERIALS USED FOR CAR EXHAUST SYSTEMS IN ROAD SALT ENVIRONMENT

Abstract

The paper presents the results and analysis of potentiokinetic investigation on materials used in elements of exhaust systems in combustion engine vehicles. The tests were performed for stainless steel X5CrNi18-10 and titanium 3.7035. The resistance to general corrosion and the susceptibility to pitting corrosion was determined for these materials in environments containing chloride ions ranging between 0.2÷1.0M. Moreover, the susceptibility to repassivation was examined. The performed tests showed high electrochemical stability of titanium and lack of the susceptibility to pitting corrosion in the applied environmental conditions. What was observed for the stainless steel was the development of pitting corrosion at ion concentration of [Cl-] > 0.6 mol/dm3, as well as the lack of influence of ion concentration on the repassivation potential.