Bu. Nambisan et al., AN APPROXIMATE MODEL FOR PREDICTING THE SIZE AND SHAPE OF WAVE-SOLDERED SURFACE-MOUNT JOINTS, JOURNAL OF ELECTRONICS MANUFACTURING, 5(3), 1995, pp. 217-233
An approximate method is developed to determine the effect of pad dime
nsions, component dimensions, conveyor angle and solder properties (su
rface tension and density) on the size and shape of solder joints form
ed during a wave soldering process. The model uses a dipping analogy t
o simulate the wave soldering operation, and is thus also applicable t
o dipping processes for soldering, pre-tinning or bumping. The study r
epresents an extension of previous work by the authors in which the ef
fect of conveyor angle was not included and the exact solution for the
molten solder capillary surface was utilized. In the present investig
ation a constant curvature approximation is introduced in the dipping
sequence as well as in the find joint configuration. This reduces the
problem to one of a geometrical nature only. The results of the model
are presented in dimensionless form, compared with the exact theoretic
al results for a horizontal conveyor, and compared with data from actu
al production joints. The fundamental concept upon which the model is
based may also be extended to through-hole and leaded surface-mount co
mponents.