No abstract

Though lead‐free replacements for SnPb eutectic alloys for reflow, wave, and hand soldering have been developed, relatively little has been reported on practical experience of lead‐free wave soldering processes. In wave soldering, the interaction between the PCB, flux, solder alloy and processing equipment makes it desirable to develop the consumables and the wave soldering machine concurrently. A crossfunctional project team was formed and a lead‐free wave soldering process developed and validated through nine months of industrial use in production of broad‐band communications technology products.

Over recent years the electronics manufacturing industry has seen a shift away from wave soldering towards reflow soldering [1]. However, although wave soldering is indeed mature (first used during the 1950's [eg 2]), there is still significant activity with novel process development to match [3]. This paper concerns a new type of noclean liquid flux for wave soldering that is based on water [4]. It provides background, including the environmental driving force and why this applies especially to wave soldering, and details the technological challenges, and how they were addressed during the development of Multicore's "Ecosol" range of water based liquid fluxes.