Pcb manufacturer how to control lead-free wave soldering process

The pcb manufacturer quality control method of wave soldering is basically the same as reflow soldering in principle, because their soldering mechanism and RC28F128K3C solder joint quality requirements are the same. Therefore, the real-time temperature curve should be controlled firstly.

The main features of lead-free wave soldering are high temperature, poor wettability and small process window. The process difficulty is much more difficult than lead-free reflow soldering. Therefore, it is necessary for pcb manufacturer to take measures from the PCB design to make the process more detailed, to improve the tin-through permeability of the through-hole, and to reduce the virtual soldering, bridging connection, and solder joint peeling etc. At the same time, it is necessary for pcb manufacturer to prevent and control Pb pollution, Cu pollution and Fe pollution.

1.The design of the PCB aperture ratio should be larger than that of leaded solder. Generally, the hole diameter of the component is specified to be 0.2 to 0.5 mm (d is the diameter of the lead wire), and the upper limit of the lead-free wave soldering should be taken. By increasing the aperture, the fill height of the solder in the insertion hole is improved by pcb manufacturer.

2. Taking various countermeasures according to the characteristics of lead-free wave soldering.

3. The distance between the two waves should be relative shorter, and the heating component is inserted between the two waves at the end of the preheating zone. Preventing the PCB from cooling down.

4. According to the solder alloy composition and the size, thickness, component size, density and other specific conditions of the assembled board, for pcb manufacturer, the technic specifications and temperature curve of lead-free wave soldering are established correctly. The specifications of the lead-free wave soldering specification include preheating temperature, warm-up time, heating rate, peak temperature and time, cooling rate, and welding time of this wave soldering.