The combined effect of stress and corrosion on mild steel

Abstract

This paper reports confirmation of the effect of different levels of tensile stress caused by quasi-static loading on corrosion growth and the mechanical properties of corroded steel. Plastic stressed, elastic stressed and non-stressed specimens have been immersed into hydrochloride acid with acidity ranging from 0.00001 to 1 Molar. Corrosion behaviours of the test specimens are measured after 7, 14 and 28 days. The mechanical properties of steel are then measured at three grinding thicknesses (0, 0.5 mm, and 1.5 mm) at different stress and corrosion combined environments to determine the effect of stress and corrosion on mechanical properties of steel and the corrosion penetration depth. Results show that the applied stress, especially plastic stress, can accelerate corrosion and contribute to the growth of corrosion-induced delamination. The results demonstrate that there are higher degrees of degradation in mechanical properties and faster growth of corrosion penetration depth for plastic stressed steel than elastic stressed and non-stressed specimens over time. The relevant mechanisms are summarized in this paper. This paper attempts to explain of cause-effect relationships between the level of imposed stress, the level of corrosion and the mechanical properties of corroded steel.