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Circuit board manufacturers will encounter the problem of warpage of printed circuit boards in the production process, and warpage will cause problems in the positioning of components; then what factors should be paid attention to during the process of printed circuit boards, or what methods can be used to avoid printed circuits? There will be no warpage when the board is used. Today, teach everyone how to deal with this problem.

Prevention method of circuit board warpage:

1. Engineering design: the inter-layer prepreg arrangement should correspond; the multi-layer core board and prepreg should use the same supplier product; the outer C/S surface area should be as close as possible, and a separate grid can be used;

2, before baking, drying board: generally 150 degrees 6-10 hours, remove the water vapor inside the board, further cure the resin completely, eliminate the stress inside the board; before the material is baked, the circuit board needs both inner and double sides !

3. Before the lamination of the multi-layer board of the circuit board, pay attention to the warp and weft direction of the board solidification sheet: the ratio of warp and weft shrinkage is different, and the warp and weft direction should be distinguished before the prepreg is laminated; the warp and weft direction should also be paid attention to when the core board is blanked; The direction of the sheet solidification sheet is the warp direction; the long direction of the copper clad plate is the warp direction;

4, the thickness of the laminate to eliminate stress After the pressure plate is cold pressed, trimming the burrs;

5, before the drilling of the baking sheet: 150 degrees 4 hours;

6, the thin plate is best not to be mechanically brushed, it is recommended to use chemical cleaning; special fixtures are used during plating to prevent the circuit board from bending and folding;

7. After the tin is sprayed, it is naturally cooled to room temperature on the flat marble or steel plate or the air floating bed is cooled and cleaned; the warping plate is treated: 150 degrees or hot pressed for 3-6 hours, and the flat and smooth steel plate is pressed, 2- 3 times baking;