2008 Volume 16 Issue 2 Pages 43-49
The development of environment-conscious soldering technology for mounting resistor units in vehicle components has become mandatory. This report describes a basic research study aimed at optimization of bonding conditions of Pb-free solders and automation of manufacturing processes. The main purposes were (1) to optimize soldering conditions in a manufacturing process and change from manual soldering to robot soldering, and (2) to confirm the usefulness of functional evaluation and demonstrate that the current practice of visual inspection is not reliable enough for evaluating soldering. As a result of experiments and parameter design studies in which generic functions and noise factors were fully examined, guidelines toward the automation of the manufacturing process were obtained. Moreover, visual inspection, which is in general use in the industry, was shown to be inadequate for evaluating the performance of soldering technology, as it cannot evaluate the internal state of the solder,which demonstrates the importance of functional evaluation.
