Analysis on wetting separation characteristics and regulation mechanisms in high-temperature SnAgCu alloy solder on dual-line parallel architecture

Three-dimensional transient physical model of solder wetting is established to simulate and analyze the wetting and separation characteristics of SAC305 alloy solder on parallel double-wire holder. The results show that under the given conditions, SAC305 alloy solder can achieve effective separation on the subtractive holder, and the separation performance of the flat-milled structure is superior to that of the ground structure. Among the influencing factors, temperature can accelerate wetting, but the enhancement effect decreases with increasing temperature. Excessively high temperature will have a negative impact on wetting uniformity and stability. The temperature of 523.15K, at which the growth rates of wetting spreading area and solder distribution inhomogeneity decrease to nearly 1%, should be selected as the control temperature. The filling speed can increase the initial kinetic energy but may also cause wetting instability. A speed of 0 mm/s is appropriate. Increasing the droplet volume accelerates wetting and spreading, but an excessively large volume will lead to difficulty in separation. Under the conditions shown in this paper, the droplet volume should be controlled below 0.216 microliters(μL). Combined with experiments, this paper conducts comparative verification on the manufacturing configuration and the setting of control parameters. The results show that the influence trends are in good agreement with the simulation analysis, thus providing a basis for subsequent control practices of wetting and separation.