Experimental investigation of the effect of skin-pass rolling reduction ratio on corrosion behaviors of AISI 304 stainless steel sheet materials

Abstract

This study was carried out in order to reveal the effect of reduction ratio, one of the parameters of the skin-pass rolling manufacturing process of sheet metal materials, on the corrosion behaviours. In this experimental study, AISI 304 stainless steel sheet material samples were subjected to skin-pass rolling process with different reduction ratios (0.5%, 2.0%, 4.2% and 7.2%). The corrosion behaviours of skin-pass rolled AISI 304 stainless steel sheet material samples in 3.5% chloride solution was determined by potentiodynamic polarization curves. The changes in the surfaces were evaluated together with the surface roughness measurements and microstructure images. It was concluded that the increase in skin-pass rolling reduction ratio increased the corrosion resistance. The arithmetic mean roughness (Ra) did not give sufficient results to prove the finding that corrosion resistance improves as the reduction increases. The change of valleys and peaks in the roughness profile of the skin-pass rolled samples before and after corrosion was found to be evidence that the increase in reduction ratio improves corrosion resistance. As the skin-pass rolling reduction ratio increased was determined in the microstructural images that the amount of oxide layer increased and this situation was clarified from x-ray spectroscopy (EDS) findings. Electrochemical measurements, surface roughness profiles, microstructure images, and EDS analyses were obtained with results that support each other.