Why does automobile circuit board PCB appear to dump copper?
- Release on:2018-10-09
1. PCB circuit design is unreasonable. Designing thick lines with thick copper foil will also cause excessive etching of the line and copper. (Key board PCB supplier china)
2, copper foil is excessively etched, the electrolytic copper foil used on the market is generally single-sided galvanized and single-sided copper plating. Common beryllium copper is generally galvanized copper foil of 70um or more, red foil and ash foil of 18um or less. There have been no batches of beryllium copper.
3. Local collision occurs in the PCB process, and the copper wire is separated from the substrate by external mechanical force. This bad performance is poor positioning or directional, and the detached copper wire will have obvious distortion or scratch/impact marks in the same direction. Peel off the copper wire at the bad place and look at the copper foil surface. It can be seen that the copper foil surface is normal in color, there will be no side erosion, and the copper foil peeling strength is normal.
4. Under normal circumstances, the copper foil and the prepreg are basically combined as long as the laminate is hot pressed for more than 30 minutes, so the pressing generally does not affect the bonding force between the copper foil and the substrate in the laminate. However, in the process of stacking and stacking laminates, if the PP is contaminated, or the damage of the copper foil surface is damaged, the bonding strength of the copper foil and the substrate after lamination may be insufficient, causing the positioning or sporadic copper wire to fall off. However, there is no abnormality in the peeling strength of the copper foil near the test strip.