Process for stainless steel pickling and passivation without using nitric acid

摘要

Process for stainless steel pickling consisting in placing the material to be treated in a bath kept at a temperature ranging from 30 DEG C. to 70 DEG C. and containing: a) H2SO4 b) Fe3+c) HF d) emulsifiers, wetting agents, polishing agents, acid attack inhibitors; the bath being kept under agitation with: an air flow and continuously fed with a quantity of oxidizing agent adjusted to the bath redox potential to be kept at 250 mV min.