The functional quality of stainless steels is not only determined by the chemical
composition i.e. the steel grade but also dependant on their surface finish which is achieved by
mechanical and/or chemical treatments. Stainless steels 1.4301 (AISI 304) and 1.4404 (AISI
316L) having been given different surface preparations (grinding, pickling, passivating) were
investigated with electrochemical procedures using current noise as a tool to characterize the
quality. Electrochemical current noise showed to be useful in respect to differentiate between
the properties obtained by these treatments and can be developed into a useful tool in order to
determine the quality of a supplied product.