The pcb sheets is mainly refers to 1100 H18 aluminum entry sheet for Printed Circuit Board, the thickness is 0.13～0.18mm±0.01mm. In the PCB industry, the application of the circuit board drilling sheet is very important. If there is a problem with the via process, the device cannot be fixed on the circuit board, which will affect the use, and the whole board will be unusable.
Now let us understand the main requirements of the drilling pcb sheets?
1, The resin composition of the plate itself should not be too high, otherwise it will form molten resin balls and stick to the hole wall. The higher the thermal conductivity, the faster the heat generated during the drilling process, the lower the temperature of the drill bit, and the better the drill bit annealing.
2, There is a certain surface hardness of aluminum entry sheet to prevent burrs on the upper surface of the drilling. However, wearing a drill is not difficult.
3, When the drill bit is in contact with the drill bit, there must be a certain degree of rigidity to prevent the drill press from vibration, and also a certain degree of elasticity, so that the position of the drill bit and the bit to be drilled can be accurately aligned. If the surface of the buffer board is hard and slippery, the small-diameter drill bit may slip from the original hole position and drill an oblique elliptical hole on the circuit board. The material should not have impurities that evenly produce uneven soft and hard nodes, otherwise the drill bit is easy to break.
The upper backing board used in China is mainly aluminum pcb sheets, aluminum sheet as the upper backing board for ordinary double-sided drilling, and the hardness is suitable to prevent burrs on the upper surface of the drilling. Because aluminum has good thermal conductivity and rigidity and elasticity, it has a certain heat dissipation effect on the drill bit.