Lead-freesolder wire Material CategoryMaterial AdvantageMaterial WeaknessApplication SN-CuSn-Cu alloy is the cheapest lead free solder material in the wave soldering process,and it can be compatible withe the main polished surface of lead.Therefore,many companies count it as the first choice of lead free solder.According to the Nnrtel test,we know that Sn-Cu alloy's thermal fatigue is better than the traditional Sn-Pb.And because of the eutectic alloy is the sole melting point,rather than the general scope of the favoured melting point.Special attention its melting point is higher thn SnAgCu alloy which is 227°C.And the alloy’s market price is the tin-lead eutectic 1.5 times.On the other hand,its melting point is quite high and its machanism is not that good,it’s not the weakness in some way though.1.Tin wire of the manual iron welds.2.The solder bar of the wave soldering products.