PCB Technical - Preparation technology of PCB metal surface

In order to meet today's demanding technical standards, the surface condition of the printed circuit board is an extremely critical factor. Therefore, manufacturers in various countries spend a lot of time and money using methods such as deburring, cleaning, brushing and grinding to adjust the state of the metal surface.

Preliminary treatment technology for metal surface of printed circuit board

Among all the materials for surface adjustment, non-woven products have the best effect. When non-woven materials are used for various polishing, brushing and deburring, it has the advantages of high strength, good durability, and long service life. The plasticity of the material is suitable for the board surface of more complicated shape. Non-woven materials can give many products the desired uniform polishing, brushing and appearance requirements. The key to the excellent performance of non-woven materials is its rebound and empty web structure. This structure allows cold running operation, thereby preventing board warpage and surface deformation.

1. Abrasive analysis of the used grinding wheel can be divided into six types at present:

1. In the abrasive series, the grinding wheel has the most cutting ability. It is specially designed for grinding materials. It can cut larger defects quickly from the hardest surface.

2. Emery cloth or sandpaper is perhaps the most widely used form of abrasive. It is not only used in metal processing, but also in other areas (such as plastic surface processing), and has a good polishing effect.

3. Steel wire wheel, used for the treatment of serious defects on the metal surface.

4. Nylon fiber brushes are used to treat minor defects or oxide films on metal surfaces.

5. The polishing cloth wheel can cut a small amount of metal and can provide mirror polishing.

6. Non-woven abrasive is an ideal material for controlling material cutting and surface cleaning. The abrasive particles are bonded to the surface of the synthetic circular column, and the surface of the plate is deburred or brushed at different speeds to achieve pretreatment. The ultimate goal.

Two, clean and brush

In the PCB circuit board manufacturing process, the most widely used material is quartz sand. There are four different types and sizes of quartz sand for cleaning and brushing materials. Quartz sand is made of alumina, silicon carbide, aluminum silicate, talc and so on. The materials are made into various products, including cleaning and polishing rollers, printed circuit board brushes, etc.

Third, the surface speed of the wheel

The surface speed of the wheel is an extremely important factor, and a higher speed provides a good surface condition. In particular, it is ideal to use a high wheel speed to remove burrs generated after drilling. However, a too high wheel speed will cause overheating on the surface being brushed, reducing product life and scrapping.

Fourth, pressurization

When deburring, depending on the thickness of the board and the thickness of the copper foil, proper pressure is required. Excessive pressure will reduce the life of the product. The principle of pressurization is based on the condition and requirements of the board. Use as little pressure as possible to obtain the desired PCB technical effect.