Surface treatment of the AISI 316L after welding and study of corrosion behaviour

Abstract

This work deals with impact of the surface treatment on corrosion resistance of the stainless steel AISI 316L welded by the TIG method. Chemical and mechanical treatment changes chemical composition, component size, surface free energy and topography of surface. These specifications have a great influence on corrosion resistance of the stainless steel which is caused by existence of stable, thin and well adherent passive layer. Surfaces of the welded stainless steel were modified by two mechanical treatment methods (grinding, garnet blasting) and one chemical (pickling). The properties of variously prepared surfaces were studied by SEM. Corrosion behaviour of the specimens with different surface treatment was investigated by exposition tests in the 6% FeCl₃ solution and also by the electrochemical polarization in the NaCl solution.