PCB board are widely used in electronics, computers, electrical appliances, mechanical equipment and other industries. It is the support of components and is mainly used to connect components to provide electricity. Among them, 4-layer and 6-layer circuit boards are the most common and widely used. , Different levels of PCB layers can be selected according to industry applications.

Corrosion process of PCB circuit board:

The etching process of the printed circuit board is usually completed in the corrosion tank. The etching material used is ferric chloride. The solution (FeCL3 concentration 30%-40%) is cheap, the corrosion reaction speed is slow, the process is easy to control, and it is applicable Corrosion of single and double-sided copper clad laminates.

The corrosive solution is usually made of ferric chloride and water. The ferric chloride is a yellowish solid, and it is easy to absorb moisture in the air, so it should be sealed and stored. When preparing the ferric chloride solution, 40% ferric chloride and 60% water are generally used, of course, more ferric chloride, or warm water (not hot water to prevent the paint from falling off) can make the reaction faster Note that ferric chloride is corrosive. Try not to touch your skin and clothes. Use a cheap plastic basin for the reaction vessel, just fit the circuit board.

Start to corrode the PCB circuit board from the edge. When the unpainted copper foil is corroded, the circuit board should be taken out in time to prevent the paint from eroding away useful circuits. At this time, rinse with clean water, and scrape off the paint with bamboo chips by the way (at this time, the paint comes out of the liquid and is easier to remove). If it is not easy to scratch, just rinse it with hot water. Then wipe it dry and polish it with sandpaper, revealing the shiny copper foil, and a printed circuit board is ready.

After the printed circuit board is corroded, the following treatments must be carried out after the printed circuit board is corroded.

1. After removing the film, the printed circuit board that has been rinsed with clean water is soaked in hot water for a period of time, and then the coated (pasted) film can be peeled off. The unwiped area can be cleaned with thinner until it is clean.

2. Remove the oxide film. When the coated (pasted) film is peeled off, after the printed circuit board is dried, wipe the board repeatedly with a cloth dipped in decontamination powder to wipe off the oxide film on the copper foil, so that the printed circuit and soldering The bright color of copper is exposed on the disk.

It must be noted that when wiping the copper foil with a cloth, it should be wiped in a fixed direction to make the copper foil reflect the same direction, which looks more beautiful. Rinse the polished printed circuit board with water and dry it.

3. Applying flux In order to facilitate soldering, ensure the conductivity of the printed circuit board and prevent corrosion, after the printed circuit board is finished, a layer of flux must be applied to the copper foil of the printed circuit board to prevent oxygen.