Method for the thermochemical passivation of stainless steel

摘要

The present invention relates to a process for improving the heat and corrosion resistance of stainless steel by means of a novel passivation process. This process comprises a chemical treatment with an aqueous solution comprising a complexing agent combination of at least one oxidant, a subsequent rinsing and a subsequent treatment at elevated temperature in an oxygen-containing atmosphere. The stainless steel surfaces obtained according to the invention have a homogeneous passive layer having increased chemical resistance and resistance to thermal discoloration.