The wave soldering temperature depends on the temperature required to form the best state of the solder joint. Here it refers to the temperature of the solder melt. There is often some deviation between the actual temperature and the temperature set by the computer. Actual measurement must be carried out before welding. Use a calibrated thermometer or electronic thermometer to measure the temperature at various points in the tin bath. Modify the parameters set by the computer according to the actual temperature value. When the design temperature is basically reached, run without load for 4 minutes to make the temperature distribution uniform before welding.
When the ambient temperature changes significantly, the process temperature of PCB preheating will fluctuate up and down, and the welding effect will change immediately. If the change is too large and the preheating process temperature exceeds the limit, it will cause solder joint formation, virtual soldering, solder layers that are too thick or too thin, bridging and other undesirable phenomena. It can be seen that the influence of environment and temperature on the temperature-time curve of the preheating process.
The temperature of the wave soldering furnace affects the welding quality. If the temperature is too low, the fluidity of the solder wave will become poor and the surface tension will be high, which will easily cause welding defects such as virtual soldering and pulling, and the characteristics of wave soldering will be lost. Advantages: SOLDERING is generally not used as a directly stressed structural member. Each 6N solder joint withstands a force of 3N. This is different from stud welding. The force is only the instantaneous moment of assembly and there is enough welding area support. If the welding surface is bent and the buckle pins are in a figure of eight, there will be no pull-out. If the structure is changed, each 6N solder joint will bear a force of 3N. This is different from stud welding. The force is only the instantaneous moment of assembly and there is enough welding area support. If the welding surface is bent and the buckle pins are in a figure of eight, there will be no pull-out. If the structure is not changed, if the temperature is too high, it may cause component damage and increase solder oxidation. Evaluation criteria: The solder alloy + flux combination can achieve excellent wetting effect. Evaluation method: The slag reducing agent adopts the wetting balance method. For the Sn-0.7Cu solder alloy + lead special flux/low VOC flux combination, the solder The optimal temperature of the tank is 260-270°C; the temperature of composite double-sided panels is generally about 10-25°C higher than that of single-sided panels; it is better to use substrate materials with higher Tg in lead wave soldering because they have better impedance capabilities. Lead wave soldering does not have a great impact on components.
This article is reproduced from the Guangsheng De wave soldering web page link