Znnial 130

Znnial 130 Alkaline Zn-Ni alloy plating process (Barrel and Rack)

It is suitable for barrel applications that require 12 -15% nickel alloy coverage. Good distribution. This alloy gives exceptional sacrificial corrosion resistance and get the metallic luster film.

Characteristics of The Process

• Good corrosion resistance (equivalent to 4-5 times of zinc plating process)
• Excellent adhesion at high temperature.
• Accepts ELV, RoHS regulation corresponding trivalent chromium chemical conversion treatment (colorless/black). And also accept hexavalent chromium passivation.
• The cathode current density is 3 A/dm2 (about 0.2 μm/min). 
• HV 350~450.

 

Required materials

Znnial 130 MU	Makeup
Znnial 130 B	Brightener
Znnial 130 C	Complexing agent
Znnial 130 N	Ni Replenisher
Znnial 130 L	LCD Booster
Znnial 130 S	Softener

 

Operating Data

 

Method of Make up

• Clean the tank and add deionized water up to 2/3 of the tank ;
• add the required sodium hydroxide and dissolve it;
• Put the steel anode basket which containing high purity (99,99%) zinc ingot into the tank. Remove the anode basket when the zinc concentration in the solution dissolved to 6g/l ( calculate according to the final volume );
• Add water, retain the volume allowance of additives, stir evenly, sampling, analysis;
• Mix the Znnial 130 C and Znnial 130 N first, then add to the tank;
• Add other additives as required.

Maintenance and supplementation

Suggestion for how to replenish,

Znnial 130 S	100 ml/KAH(80-150) Do Hull cell test regularly
Znnial 130 B	50 ml/KAH(0-50) Not add if no needs bright film
Znnial 130 N	650 ml/KAH(550-800) Adjust according to the concentration of nickel
Znnial 130 C	130 ml/KAH(100-200) Adjust according to the amount of precipitation.

 

• Management of metal concentrations

Adjust the soaking time of zinc plate and zinc sheet in zinc dissolution tank and manage zinc concentration in the most suitable range. Adjust nickel concentration and manage it to the most appropriate range.The following table shows when the nickel eutectoid rate is 13 percent.

 

	Optimal value	Acceptable range
Zinc concentration (g/l)	6.0	5～10
Nickel concentration (g/l)	1.6	1.5～2.0
Zinc/Ni	5.0	4.0～6.0

 

• How to control the concentration of Sodium hydroxide and sodium carbonate

As production begins, sodium hydroxide is managed taking into account the fact that carbonic acid in the air enters into the production of sodium carbonate. Here is following methods.

Sodium hydroxide concentration (g/l)=130-0.33× sodium carbonate concentration (g/l)

 

About standard value and management range, please follow the table below

	When Make up	Acceptable range
Sodium hydroxide concentration g/l	130	110～140
Concentration of sodium carbonate (g/l)	0	Below 60
Alkali concentration (g/l)	130	110～130

Also keep the sodium carbonate concentration below 60 g/l.