HotLine:
Basic Requirements for Lead-free Electronic Solder for Electronic Assembly (Part III)
It has good solderability under the condition of existing equipment and non-cleaning flux. The electronic solder should have sufficient humidity and can be used with conventional non-cleaning flux. Because the cost of inert treatment of wave crest is not too high, it can accept the requirement of wave crest welding plus inert environment. But for SMT reflow welding, it is better for alloy to have the ability of reflow welding in air, because the cost of inert treatment of reflow furnace is higher.
Good physical properties (strength, tensile strength, fatigue, etc.) electronic solders must be able to provide mechanical strength and reliability that 63Sn/37Pb can achieve, and there will be no protruding fillet welds on through-hole devices (especially for alloys with large temperature range of solid-liquid coexistence).
Production repeatability/melting point consistency, electronic assembly process is a mass manufacturing process, requiring a high level of repeatability and consistency. If the composition of some electronic solders can not be re-manufactured in large batches, or the melting point of some electronic solders can not be considered because of changes in composition during mass production. The electronic solder composed of more than three components will often be separated or changed, which makes the melting point unstable. The higher the complexity of the alloy, the greater the possibility of its change.
