The quality of the soldering depends mainly on the ability of the solder to wet the surface of the weldment, that is, the weld-ability of the two metallic materials.If the weld-ability of solder joints is poor, it is impossible to weld qualified solder joints. Solder-ability refers to the weld and solder in the appropriate temperature and the role of flux, the formation of a good combination of performance.
Welding time: refers to the time required for physical and chemical changes during the welding process. It includes the welding time to reach the welding temperature, the melting time of the solder, the flux function and the time of forming the metal alloy. PCB board welding time should be appropriate, too long easy to damage the welding parts and devices, too short to meet the requirements.
Many types of flux, the effect is not the same, according to the use of different welding processes, welding materials to choose a different flux. Excessive flux, flux residual side effects will increase. The amount of flux is too small, the welding effect is poor. The flux used in the welding of electronic products is usually rosin flux. Rosin flux no corrosion, remove the oxidation, enhance the flow of solder, to help wet the welding surface, so that bright and beautiful solder joints.
Thermal energy is an indispensable condition for welding. In soldering, the effect of heat is to spread the solder to the element and to raise the temperature of the weld to the appropriate soldering temperature to produce a metal alloy with the solder.
In order to achieve a good combination of solder and weldments, the surface of the weldment must be kept clean. Even welders with good weld-ability, if there are oxide, dust and oil on the surface of the weldment. The staff of the circuit board factory must be cleaned before welding, otherwise it will affect the formation of the alloy layer around the weldment, thus failing to guarantee the welding quality.