The high temperature storage of resin solder wire is mainly used to examine the influence of temperature and time on the reliability of resin solder wire under storage conditions. For the solder joints of the resin solder wire, it is often encountered in high temperature storage in the use environment. The impact of high temperature on the solder joints is mainly reflected in the growth of intermetallic compounds at the interface of the solder joints. When the intermetallic compounds grow thick, they may also Kirkendall voids will be produced, and the strength of the solder joints of the solder product will decrease. That is, high temperature stress can lead to solder joint aging or early failure. This accelerated aging process can be described by the Class A law.

At present, there is no test standard specifically for the high temperature test of solder wire solder joints. The selection of general solder joint high temperature test conditions can refer to JEDEC's standard JESD22-A103C-2004. The level of high temperature stress can be divided into 7 grades A-G. For PCBA For the solder joints on the PCB, generally choose condition A or G, because other temperature conditions may lead to other new degradation failure mechanisms, such as exceeding the Tg of the PCB substrate, which will lead to severe deformation of the PCB, which will generate new stress on the solder joints , will inevitably lead to the emergence of new mechanisms. In addition, some solder bar solder joints can also cause similar problems. In addition, due to the single high temperature stress and the limitation of surrounding factors, the test time is generally longer than 1000h. During the test, it is best to have testing equipment for testing, so as to find failed samples as soon as possible. The growth status or speed of voids can also be examined by scanning electron microscopy after slicing, so as to achieve the purpose of preliminary evaluation of solder joint reliability.