With the rapid development of SMT technology and some brands of solder wire and high-seal packaging technology for components, it is difficult to find the hidden solder joint defects of many brands of solder wire with intuitive methods. The quality and reliability of solder joints must be adapted to this test technology Therefore, various advanced testing equipment and new technologies emerge in an endless stream, but the high price and difficult maintenance make it unaffordable for most enterprises in the industry. Dyeing and penetrant testing technology has been applied to the quality inspection of solder joints, especially SMT-assembled BGA and other array solder joints for many years, and has been proved to be very effective. Its advantages are simple operation, low cost, and almost every manufacturer can complete it. In addition, the quality information obtained is also rich and accurate, and sometimes the information obtained is even better than that obtained by another destructive analysis method - metallographic section. The quality information is more abundant. Unfortunately, this test method is destructive, and once the test is performed, the sample must be discarded. Nevertheless, the widespread use of dyeing and infiltration methods in the inspection and evaluation of solder joint quality is an inevitable trend.

     It is precisely because of the simplicity of the method that many brand solder wire and solder bar testers do not study the details carefully, which often leads to deviations in many solder tests, and serious errors may be obtained.