The effect of surface treatment AISI 316L welded joints on its corrosion behaviour in chloride solution

Abstract

Investigation of different surface treatment effects on the corrosion resistance of AISI 316L stainless steel welded joints is presented in this paper. Research was conducted using gravimetric tests in 6 wt. % ferric chloride solution as well as polarization measurements in 1 mol dm-3 NaCl solution. Additionally, the mechanism of corrosion attack developed on the steel surface was analyzed by optical microscopy, scanning electron microscopy and energy dispersive X-ray analysis. Prior to the measurements, the surface of stainless steel welded joints samples was treated by ultrasonic cleaning in ethanol (sample A), ultrasonic cleaning and pickling (sample B), ultrasonic cleaning, pickling and passivation (sample C) and grinding, polishing, ultrasonic cleaning, pickling and passivation (sample D). The results have shown that the corrosion resistance of 316L SS welded joints has increased due to the surface treatment.