The standard range of wave soldering soldering temperature is usually between 240℃ and 260℃. Specifically, the setting range of the soldering temperature is generally 250°C to 280°C, while the soldering temperature should be 245°C ± 10°C for lead-free wave soldering. For leaded solder, the melting point of the commonly used 63/37 solder bar is about 183°C, and a wave temperature setting of about 230°C is preferred, with a temperature range of 230°C ± 10°C. Lead-free solder has a higher melting point, generally set the temperature range of 255 ℃ ± 5 ℃. Factors affecting the wave soldering temperature setting.
Wave soldering temperature settings are affected by a number of factors.
Firstly, the proportion of solder is an important consideration, as different proportions of solder have different melting points, so the appropriate soldering temperature needs to be determined according to the type of solder being used. Secondly, the characteristics of the circuit board and the components on which it is mounted are also important references for setting the temperature. Larger circuit boards and thicker circuit boards may require higher temperatures to ensure that the solder can be fully melted and cover the entire pad. In addition, different types of components have different sensitivities to temperature, and some components may be more sensitive to high temperatures, so the soldering temperature needs to be controlled in a lower range. Finally, the preheating temperature is generally 130~150 ℃, preheating time is 1~3 minutes, good preheating temperature control can prevent false soldering, false soldering and bridging, reduce the thermal shock of the solder wave on the substrate, and effectively solve the problem of PCB warping, delamination, deformation and other problems in the welding process.
The effect of too high or too low wave soldering temperature
Wave soldering welding temperature is too high or too low will have an adverse effect on the quality of welding. When the temperature is too low, it may lead to weak solder joints, causing poor soldering; and if the temperature is too high, it is easy to oxidise, volatilise or deteriorate the solder, which adversely affects the soldering results. High temperatures may also cause tin to have charring or volatilisation, affecting the quality and stability of the solder joints; long periods of high temperature environment, the soldered parts may be deformed, cracking and other problems, which in turn affects the reliability and stability of the entire circuit board; in addition, high temperatures may also damage equipment and parts, increasing the cost of maintenance and risk.
