PROCEDURE FOR DECAPING AND PASSIVING STAINLESS STEEL IN THE ABSENCE OF NITRIC ACID.

摘要

PROCESS FOR THE DEOXIDANT TREATMENT AND STAINLESS STEEL PASSIVATION WITHOUT THE USE OF NITRIC ACID. A PROCESS FOR DEOXIDANT TREATMENT AND STAINLESS STEEL PASSIVATION USING A BATH OF THE FOLLOWING INITIAL COMPOSITION: H2SO4, AT LEAST 150 GR / LT FE3 +, AT LEAST 15 GR / LT HF, AT LEAST 40 GR / LT H2O2 STABILIZED, 1-20 GR / LT NON-ION SURFACTANTS AND ACID ATTACK INHIBITORS, 1 GR / LT, IN WHICH AN AIR JET AND A QUANTITY OF H2O2 UNDERSTANDED BETWEEN 0.3 AND 1 GR / LT PER HOUR CONTINUED, CONTROLLED TO MAINTAIN A POTENTIAL OF REDOX OF BATHROOM TO LESS THAN 350 MV.