Effect of sulphuric acid concentration on the rate of tribocorrosion of iron

Abstract

Corrosion and tribocorrosion tests of iron in sulphuric acid at different concentrations were performed in order to elucidate the relationship between corrosion and wear and the role of surface films. Coefficient of friction, material loss rates and surface morphology of iron rubbing against alumina were monitored in sulphuric acid solutions of concentrations ranging from 2 M up to 18 M. It was found that the material removal rate under tribocorrosion as a function of acid concentration reaches a maximum at 8 M. The simultaneous action of wear and corrosion may significantly affect the material removal mechanisms observed under static corrosion conditions. The films formed by corrosion products at the iron surface are responsible for surface smoothing. © 1993.