Galvanized steel oxidation process introduced

Galvanized 409 stainless steel plate oxidation process introduced
(1) black handle. By some special treatment, as galvanized steel 1Cr13,3Cr13,4Cr13 on black nickel and zinc plating layer blackened.
     ① black nickel plating solution composition and soil conditions Arts
     Molybdate press [(NH4) 6Mo7O24.4H20] 30 ~ 40g / L
     Nickel sulfate (NiS04.7H2O) 120 ~ 150g / L
     Boric acid (H3BO4) 20 ~ 25g / L
     a pH value of 4.5 5.5
     20 to 25 ℃ temperature
     Cathode current density 0.15 ~ 0.3A / dm2
     15 hours a 20min
     ② black zinc coating solution composition and process conditions
     Molybdate press [(NH4) 6Mo7O24.4H20] 300g / L
     Aqueous ammonia (NH3 · H2O) (d = 0.89) 600mL / L
     Temperature 30 ~ 40 ℃
     Time 10min
     (2) Galvanized - black nickel plating process. Electrolytic degreasing → washing → weak corrosive (sulfuric acid 110mL / L, thiourea 10g / L, wash clean right amount) → washing → galvanized [NH4Cl220 ~ 280g / L, ZnCl230 ~ 35g / L, H3BO325 ~ 30g / L, polyethylene diol 1 ~ 2g / L, thiourea 1 ~ 2g / L, detergent 0.5 ~ 1mL / L, pH5.6 ~ 6.0, temperature 10 ~ 35 ℃, the cathode current density (Dk) 1 ~ 1.5A / dm2, the time 30s] → washing → retreat zinc (ZnCl250g / L, HCl50mL / L, room temperature, and the time to do back up) → washing → weak corrosion (ZnCl250g / L, HCl50mL / L, room temperature, and the time to do back up) → washing → galvanized
     (Time 5min) → → washing → black nickel plated closed treatment (CrO32.5 ~ 5g / L, pH1.5 ~ 5, temperature 10 ~ 30 ℃, time 10 ~ 20s) → washing → dry (less than 500 ℃)
     (3) galvanized black treatment process. Pre-galvanized and pre-treatment to black nickel plating process → galvanizing same (time 1.0 ~ 15min) → washing → → washing → black zinc coating and drying.