Dongguan Debailong Electronic Technology Co., Ltd.

 In principle, the higher the surface wave solder contact with air is greater, oxidation is more serious, the tin slag more. So the wave should not be too high, generally does not exceed the printed circuit board thickness 1/3, i.e.peaks top than printed circuit board welding surface, but can not exceed the components. Secondly, if the wave is not stable, liquid solder from peak when he got back into the molten solder air inside, accelerate the oxidation of tin in the soldering process, plating the surface of a printed circuit board and electronic component pins Tongdou will continually dissolve into molten solder. Between copper and tin will form Cu6Sn5 intermetallic compound, the compound melting point of 500 DEG C, so it is in solid form. At the same time, because the compound density is 8.28g/cm3, while the Sn63Pb37 solder density is 8.80g/cm3, so the general compound Will present the rubbish floating on the surface of the liquid solder. Therefore, copper removal work is very important. The operation is as follows: stop wave, normal operation of stove heating device, firstly various tin surface residue clean, with mercury like mirror. Then the tin temperature reduced to 190-200 DEG C (at this time is still in the liquid then, using iron solder) tools such as stir solder tin solder within 1-2 minutes to help the copper compound float and then rest for 3-5 hours. Because of the density of small tin copper compounds, static after tin copper compounds will naturally float on the surface of the solder, with the iron tools such as tin and copper compounds can be cleaned off. If adding amount of pure tin to tin copper wire content better.