Black zinc passivation potion
Z N-117 trivalent chromium black zinc water
Free of hexavalent black passivator, suitable for electroplating and barrel plating.
Sealants, when used together, can be produced in a dense black passivation layer of zinc chloride acid coating.
Use with sealer, 5% salt spray test white rusted greater than or equal to 72 hours.
Impurities perform well.Plating solutions have a long life.Plating solutions have a long life. Easy to operate and maintain.
in barrel plating or automatic line passivation, collision or friction scratches will automatically repair.
Operating conditions
Passivation operating conditions |
best value |
range |
Zn-117 trivalent chromium black zinc water |
200 is mL / liter |
180-220 ml / liter |
PH |
1.6 |
1.6-2.0 |
time |
30 seconds |
20-60 seconds |
temperature |
25 ℃ |
20-30 ℃ |
|
||
Closed operating conditions |
best value |
range |
Sealant 76 |
Rack plating: 100 mL / liter Barrel: 150 mL / L |
Rack plating: 50-150 ml / liter Barrel: 50-250 ml / liter |
Sealant 77 |
. 5 mL / L |
0-10 ml / liter |
PH |
4.0 |
3.8-5.5 |
time |
10 seconds |
5-20 seconds |
temperature |
40 ℃ |
30-50 ℃ |
Stir |
Gentle stirring |
equipment
Plating cylinder: stainless steel plastic coated with heat resistance properties.
Stirring: In hanging plating, it is recommended to use partial stirring or plating solution stirring to ensure uniform passivation effect.
PVC or polypropylene coils are recommended.
Open cylinder configuration
Fill the cylinder with the required amount of water and add Zn-117 trivalent chromium black zinc water.
Let stand for 15 minutes and continue to stir until the additive reacts.
Adjust pH to 1.8-2.2 with 10% sodium hydroxide. If you need to reduce the pH, use 50% nitric acid.
Process flow
Zinc plating → water washing → water washing → activation → water washing → black passivation (Zn-117 trivalent chromium black zinc water) → water washing → water washing → sealing (sealant 76) → drying (60-120℃)
maintenance
The optimum state of the passivation solution can be maintained by regular supplement of Zn-117 trivalent chromium black zinc water.
Reduce pH by adjusting with dilute nitric acid. Raise pH by adjusting dilute sodium hydroxide solution.
The amount of additives added should be controlled by solution analysis prior to the establishment of a regular supplement schedule.
Supplementation can also be made based on the surface area of the work piece and as a reference. For every 100 SQM (10 SQFT) of passivation, approximately 20-25 ml of Zn-117 trivalent chromium black zinc water will be required, depending on strip loss.
Analysis and control
1. Draw 2 ml of Zn-117 trivalent chromium black zinc water plating solution and inject 250 ml of conical flask.
2. Add 50ml of pure water.
3. Adjust pH to about 10 (color to green, use 10-15 ml 10% sodium hydroxide)
4. Add 1.0-1.5ml of hydrogen peroxide
5. Boil the solution for 30-45 minutes until 1/3 of its volume remains. The excess hydrogen peroxide is completely evaporated.
6. After the solution cools, add 100 ml of pure water.
7. Add about 15ml of concentrated hydrochloric acid to change the color of the solution from yellow to orange. When the solution gets hot, it needs to be cooled again.
8. Add 4-5 ml 10% potassium iodide (dark red) and starch solution.
9, with 0.1N sodium thiosulfate solution titration until the solution becomes dark color disappear.
Calculation: Zn-117 trivalent chromium black zinc water concentration (ml/l)= reading * constant of sodium thiosulfate *50*0.1
Wastewater treatment
Zn-117 trivalent chromium black zinc water passivation solution contains trivalent chromium compounds. Lime was used to adjust pH to 9.0 to remove precipitated heavy metals. Discharge only after the solution is clear.
Matters needing attention
Zn-117 trivalent chromium black zinc water and its operating liquid belong to acidic substances, and the operation should be careful. Nitric acid can cause serious burns to the skin and eyes. Wear protective clothing, goggles and a mask when handling. In case of contact, rinse immediately with plenty of water.
FAQ
1. Q: Do you make the products yourself? Are you a trader or a manufacturer?
A: Yes, the products are produced by our company. Our company is a manufacturer focusing on the R&D and manufacturing of environmental protection electroplating additives. Our factory has 5000 square meters with an annual capacity of 15000 tons.
2. Q: Can your company send samples for trial?
A: We can provide samples for trial.
3. Q: What is the quality of your products?
A: Our company all products core raw materials is used by Germany BASF, American Dow Chemical and other international brand products. The production process is strictly in accordance with the ISO9001 quality management system, from the incoming inspection, product inspection, according to the strict inspection standard, ensure that every drop of products qualified. Product quality you can rest assured, like BYD, Huawei, Foxconn such enterprises are also using our products.
4. Q: How long is the shelf life of your products?
A: The shelf life of our products is two years. If you do not use up the products within a short time after you buy them, we suggest you store them in a cool place, not in the sun or in a high temperature environment.
5. Q: Are your products environmentally safe?
A: Our products have passed the SGS test and are recognized as "Green and Environment-friendly Promotion Products". Many auto parts and electronic products which use our products can pass the strict environmental protection test when they are exported to Europe and America. Therefore, we can be trusted in terms of environmental protection and safety.
6. Q: Can your company provide technical services?
A: Yes, our company has a technical service team of more than 10 people. The technical engineers all have more than 20 years' experience in electroplating factory. They can provide customers with comprehensive technical of pre-sales and after sales.
7. Q: Is it possible to visit your company?
A: Yes, of course. You are very welcome! We can meet you at Jieyang airport, If you can come to our city. Also you can visit our factory through live video.
8. Q: Can you customize products according to our needs?
A: Yes, our company has research and development strength, the product formula derived from Europe and the United States laboratory, European and American engineers technical support, work together with domestic universities. Our company has a member of Guangdong province expert enterprise workstation, Shantou university science and technology correspondent workstation, Jieyang city environmental protection e