How to understand the characteristics of eutectic solder wire?

How to understand eutectic solder wire

Eutectic refers to the phenomenon of eutectic welding at relatively low high temperatures. Eutectic alloys directly transform from liquid to solid without going through the plastic stage, where the plastic stage is liquid and an equilibrium reaction of two solids occurs simultaneously.

In the solder wire, there is tin(Melting point232℃)And lead(Melting point327℃)A metal alloy composed of tin63%And lead37%The composed solder wire is called eutectic solder wire and is often referred to as6337Solder wire. So the melting point of this kind of solder is183Degree. When the content of tin is higher63%,The crystallization temperature is too high, that is, the strength of the solder wire is effectively reduced, and the melting point of the overall solder wire alloy is too high. When the content of tin is no more than10%when,The welding quality of this solder wire is poor,Hair extensions are brittle.,The performance of the solder lubrication system has weakened.

The characteristics of eutectic solder wire

At eutectic high temperatures, solder wires can transform from solid to liquid at any time without going through a semi-molten state. The melting point of eutectic solder is slightly lower than that of non-eutectic solder wires of the same alloy composition, thus reducing the possibility of damage to the electronic components being soldered. Moreover, since eutectic solder wires usually transform from liquid to solid at any time, this can also reduce the occurrence of false soldering. This is the most perfect state during the soldering process, which is why eutectic solder wires are widely used. Besides,6337Eutectic solder wire also features high strength, good electrical conductivity, good fluidity, low surface tension, and is conducive to improving the quality of solder joints.