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.
