Causes Of Desoldering Of Tungsten Steel Strips

① The brazing surface of tungsten steel has not been sanded or polished before welding. The oxide layer on the brazing surface reduces the wetting effect of the solder and weakens the bonding strength of the weld.
② Improper selection and use of brazing flux can also cause desoldering. For example, when borax is used as brazing flux, the raw borax contains more water and cannot effectively deoxidize. As a result, the brazing filler metal cannot wet the brazed surface well. , and desoldering occurs.
③ The correct brazing temperature should be 30-50°C above the melting point of the solder, and desoldering will occur if the temperature is too high or too low. Excessive heating will cause oxidation in the weld. Using zinc-containing solder will make the weld blue or white. When the brazing temperature is too low, a relatively thick weld will be formed, and the inside of the weld is full of pores and slag inclusions. The above two conditions will reduce the strength of the weld, and it is easy to desolder when sharpening or using.
④ During the brazing process, the slag is not discharged in time or is not sufficient, so that a large amount of flux slag remains in the weld, which reduces the strength of the weld and causes desoldering.