The analysis of the withdrawal force curve of the wetting curve using 63Sn-37Pb and 96.5Sn-3.5Ag eutectic solders

To analyze the withdrawal force curve in the wetting balance curve, wetting balance tests using the 63Sn-37Pb and 96.5Sn-3.6Ag eutectic solders were c onducted by varying the immersion speed, sample perimeter, and solder tempe rature. The mechanism of the withdrawal force curve was reviewed and a new method for calculating the surface tension of solders using the withdrawal force curve was introduced. The results showed that the maximum point of th e withdrawal force curve is generated when the sliding solder meets the bot tom corners of a sample and the contact angle is reduced to zero. The maxim um withdrawal force subtracted by end force can be expressed using force ba lance equation as F = p gamma. Therefore, the surface tension of the solder can be calculated by dividing the maximum withdrawal force by the sample p arameter.