Wave Soldering: A look into the future

This paper deals with the thermal, chemical and metallurgical interactions between the printed circuit board and the solder wave. Special attention is devoted to the quality of the final solder fillet as a function of each variable. The individual zones inside of a solder wave is analysed. Their effect on the printed circuit and their components is explained. Guidelines for production parameters, i.e., solder temperature, conveyor speed, depths of immersion, impedance angle, hole‐to‐wire ratio, etc., are outlined. The wave solder operation cannot be isolated from fluxing and preheating; therefore, these two additional operations are also analysed. This will be limited, however, to those aspects directly related with wave dynamics. The paper concludes with a discussion of voids and entrapment in the solder fillet as they relate to the wave soldering process. A case history is used to outline the effect of voids on quality. Suggestions are made to avoid fillet imperfections such as blow holes, voids and incomplete fillets. Proper touch‐up procedures is also covered.