Surface tension measurement of the solders by non-wetting specimen

The knowledge of actual value of surface tension is important for the understanding to several soldering aspects, such as wetting, joint shape, fluxing action and, particularly, for the quantification of solderability testing. High surface tension is required for wave soldering. This article deals with the surface tension measurement of the lead and lead-free solders. For our measurement we used one of the solderability evaluation methods known as the wetting balance method, which is used to measure wetting force. A wetting balance has been used for evaluation of solderability. This method is based on the measurement of the wetting force. We used a special technique to obtain the surface tension values of the measured solders. The measurement was carried out on the ninth different types of solders (lead and lead free) and on non-wetting measurement specimen (teflon, nonstick cylinder).