High speed electroplating insoluble anodeGalvanization is widely used as protective coating on steel nowadays As anode coating,the galvanization layer had a good effect of electrochemical protection on the based body.Electroplating occupies an important position in the surface treatment,it is accounted for 60% of the total electroplating area. Appeared With the development of electroplating technology,high speed electroplating process had been greatly improved the production efficiency.
High speed electroplating refers to that the larger than general static immersion plating on more than 10 times the current density of electroplating process.The biggest characteristic is high current density,namely the limits of high current density and high velocity of plating solutions,it can be up to 2m/s.With high velocity can effectively reduce the diffusion layer thickness of plating solution,thus improving the cathode current density,without reducing the cathode current efficiency,it commonly used for electroplating plate and wire rod.
Methods and characteristics of high speed electric galvanized
The high-speed electric zinc plating solution is basic sulfate solution,plating solution composition is simple,the main composition is zinc sulfate,sodium sulfate,sulfuric acid etc.Characterized by stable performance,high current efficiency,deposition speed,you can use higher current density.Suitable for high speed electroplating on the wire,strip.But with the disadvantage of sulfate solution crystallization is bulky and dispersing ability is poor.
High-speed electric zinc plating type
Method of Parallel FlowParallel flow method refers to keep a certain distance between anode and cathode.The electrolyte from the narrow space between the anode and cathode very well high-speed through the method and the plating,the electrolyte flow direction is parallel to the cathode components.What it needs is extremely anode and cathode,equal spacing is small and only suitable for general simple outer surface and the flat shape.Parallel flow method that the high speed flow of plating solution,anode do not moving,cathode affects the high speed.
Jet Method Jet method is electrolyte through nozzle spray flow to the cathode surface continuous plating method.Its characteristic is in local use a high current density,used for selective plating(small local electroplating) is the most effective.
Strip steel electro-galvanizing （electro-tinning）solution type：
| Application | Electro-galvanizing | Electro-tinning | ||
| Electrolyte type | Zn | Zn-Ni | PSA | MSA |
| Temperature/℃ | 45~70 | 45~60 | 50~60 | 40~65 |
| Ph | <1 | <1 | ||
| Sulfuric acid g/l) | 10~100 | 10~50 | 40~70 | <10 |
| Methyl sulfonic acid g/l | 30~60 | |||
| Phenol sulfonic acids /l | 15~60 | |||
| Sn²+ (g/l) | 27~29 | |||
| Zn as ZnSO4 (g/l) | 60~125 | 30~60 | ||
| Na as Na2SO4 | 0~100 | |||
| Ni as Ni2SO4 （g/l) | 40~60 | |||
| Fe /(g/l) | <10 | <10 | <10 | <10 |
| Chloride ug/g | <50 | <50 | ||
| Fluoride ug/g | <2 | <2 | ||
| Organic additive | ||||
| ENSA/(g/l) | 2.5~3.5 | |||
| EN/（g/l) | 4.5~5.5 | |||
| Crystal scouring agent /ml | 40~60 | |||
| Antioxidant ml/l | 15~25 | |||
| Current density A/m2 | 5k~15k | 5k~12k | 2k~4k | 2k~7k |
The level of high speed electric galvanized
Vertical high-speed electric galvanized
