Acid zinc plating
Oil removal → rust removal →→→→→→→ purification → drying.
Alkaline zinc plating
(2)
Process flow of blackening steel parts at room temperature
┌ Soak dehydrated antirust oil
│
Dry ...
Degreasing → derusting → blackening at room temperature → soaking in soap solution → soaking in spindle oil or engine oil.
│
│
Impregnating sealant
(3) Phosphating process of steel parts
Oil removal → rust removal → surface adjustment → phosphating → painting.
(4)
Electroplating process of ABS/PC plastic
Degreasing → hydrophilicity → pre-roughening (PC≥50%) → roughening → neutralization → full surface → activation → debonding → electroless nickel plating → copper plating coke →
Copper plating → semi-bright nickel plating → high sulfur nickel plating → bright nickel plating → hole sealing plating → chromium plating.
(5) PCB electroplating process
Degreasing → roughening → pre-soaking → activation →
Degumming → chemical copper deposition → copper plating → acid degreasing → micro-etching → low-stress nickel plating → bright nickel plating → gold plating → drying.
(6) Multi-layer electroplating process of steel parts
Oil removal → rust removal → cyanide copper plating → acidic copper plating → semi-bright nickel plating → high sulfur nickel plating → bright nickel plating → nickel sealing → chromium plating.
(7)
Pretreatment process of iron and steel parts (polished parts and unpolished parts)
1, polished parts → wax removal → hot dip degreasing → electrolytic degreasing → acid etching → no other electroplating.
2. Non-polished parts → hot dip degreasing
→ electrolytic degreasing → acid etching → other electroplating.
(8) Pretreatment process of zinc alloy parts before electroplating
Wax removal → hot dip degreasing → electrolytic degreasing → acid etching → alkaline copper plating →
Copper acid electroplating or copper pyrophosphate electroplating → other electroplating.
(9) Pretreatment process of aluminum and its alloys
Wax removal → hot dip degreasing → electrolytic degreasing → acid etching descaling → chemical zinc precipitation → acid leaching →
Secondary precipitation → alkaline copper or nickel plating → other electroplating.
Wax removal → hot dip degreasing → electrolytic degreasing → acid etching descaling → aluminum chromium plating → drying → spraying foam or powder → drying or roughening → finished product.
Wax removal → hot dip degreasing → electrolytic degreasing → acid etching descaling → anodic oxidation → dyeing → sealing → drying → finished product.
(10) iron chromium plating process:
Wax removal → hot dip degreasing → cathode → anode → electrolytic degreasing → weak acid etching → alkaline pre-copper plating → acidic bright copper (optional) → bright nickel → chromium plating or others.
Wax removal → hot dip degreasing → cathode → anode → electrolytic degreasing → weak acid etching → semi-bright nickel → high sulfur nickel → bright nickel → nickel sealing (selection) → chromium plating.
Chromium plating process of (1 1) zinc alloy
Wax removal → hot dip degreasing → cathodic electrolytic degreasing → acid leaching → alkaline bright copper → copper pyrophosphate (selective) →
Acid bright copper (selectivity) → bright nickel → chromium plating
(12) electric frame and dyeing process
Pretreatment or electroplating → pure water cleaning (2-3 times) → prepreg → electric frame →
Recycling → pure water washing (2-3 times) → drying → finished product.
There are many processes for electro-zinc plating. Let me show you some patented technologies.
And discloses an electro-galvanized steel plate and a galvanizing process thereof. Galvanized steel plate includes steel plate and galvanized layer on it, and the galvanized layer contains 15-8000ppm of tin. A zinc plating process for steel plate includes degreasing treatment, pickling treatment and electro-zinc plating on the surface of the treated steel plate according to the conventional process, and is characterized in that 1-500ppm of Sn2+ is added into the electroplating solution. The galvanized steel sheet of the present invention contains 15-8000ppm in the galvanized layer.
The hardness of the galvanized layer is greatly improved, which is 2 times or even higher than that of the galvanized steel plate in the prior art. In the steel plate galvanizing process of the invention, a small amount of Sn2+ is added into the plating solution, which effectively changes the organizational structure of the electro-galvanized layer, and the tin content of the electro-galvanized layer is15-8,000 ppm, so that the electro-galvanized steel plate with high coating hardness is obtained.
Hope useful to you
Galvanizing anticorrosion technology
In recent years, with the development of industry, environmental pollution has become increasingly serious, and the corrosion problem of steel materials has become more and more serious, so the protection of materials has been paid more and more attention. According to statistics, the amount of metal materials scrapped due to corrosion in the world is about 1/2 of the annual metal output. Even if two thirds of the metal materials scrapped due to corrosion can be recycled, there is still an annual metal loss of 10% every year. What's more, the value of corrosion loss can't be calculated only by losing the quality of metal, but should include the energy consumed when smelting metal. Therefore, the manufacturing value of corroded and scrapped metal materials is often much higher than the metal itself. Therefore, in order to save steel materials and ensure the normal operation of production, it is in line with China's sustainable development strategy to solve the corrosion problem of steel materials.
At present, there are two effective methods to prevent corrosion of steel materials: one is metal alloying; The second is the anticorrosion method of metal coating.
Metal alloying is to make steel materials into stainless steel containing specific metal elements to improve corrosion resistance. Due to the complicated production process and high price, the popularization of these steels is limited.
The main anti-corrosion methods of zinc coating are hot plating, electroplating, infiltration plating, thermal spraying and mechanical plating developed in recent years. Infiltration plating method has long production cycle and low surface quality, which is easy to cause missing plating; Thermal spraying method has high porosity and low utilization rate of zinc. Therefore, taking hot plating, electroplating and mechanical plating as examples, the development status of galvanized anticorrosion technology is briefly summarized.
Most anode materials used in hot dip plating, electroplating and mechanical plating are zinc. Because the standard electrode potential of zinc is low, the zinc coating on iron base is an anode coating in general corrosive medium, which plays an electrochemical protection role for the matrix. In addition, zinc can form a film with good corrosion resistance on the surface in corrosive environment, which not only protects the galvanized layer itself, but also protects the steel matrix. Galvanized coating is non-toxic, cheap and excellent in protective performance, so galvanized coating plays an important role in corrosion protection.