Solder is a fusible metal alloy used to create a permanent bond between pieces of metal. Solder is melted to wet the parts to be joined, where it sticks and after cooling it joins the parts. Suitable metals or alloys for use as solder must have a lower melting point than the parts to be joined. A known alloy of tin, it should also be resistant to oxidative and corrosive effects that deteriorate joints over time. The solder used to make the electrical connections must also have favorable electrical characteristics.
composition
Lead based
Tin-lead (Sn-Pb) solder, also known as soft solder, is commercially available with tin concentrations ranging from 5% to 70% by weight. The higher the tin concentration, the higher the tensile and shear strength of the solder. Lead tin reduces the formation of whiskers, although the exact mechanism for this is unknown. Currently, several techniques are used to mitigate the problem, including modification of the annealing process (heating and cooling), addition of elements such as copper and nickel, and insulating coatings. The most commonly used alloys for electric soldering are 60/40 Sn-Pb, which melts at 188 °C (370 °F), and 63/37 Sn-Pb, used primarily in electrical/electronic work.
- Lead based Product we serve
o Solder Stick (63Tin/37Lead)
o Solder Stick (60Tin/30Lead)
o Solder Stick (50Tin/50Lead)
o Solder Stick (40Tin/60Lead)
o Solder Ingot (30Tin/70Lead)
o Solder Ingot (20Tin/80Lead)
o Solder Ingot (10Tin/90Lead)
o Solder Ingot (5Tin/95Lead)
o And As per Client’s Requirement
Lead Free
Lead-free solder in commercial use may contain trace amounts of tin, copper, silver, bismuth, indium, zinc, antimony, and other metals. Most lead-free replacements for conventional 60/40 and 63/37 Sn-Pb solders have melting points in the range of 50 to 200 °C, although there are solders with much lower melting points. Adequate wetting ability for lead-free solder typically requires about 2% flux through the mass.
When wave soldering uses lead-free solder, a slightly modified solder pot may be desirable to reduce maintenance costs due to increased tin removal from high-tin solder.
Lead-free solder is prohibited in critical applications such as aerospace, military, and medical projects, as joints under stress are prone to metal fatigue failure. While this is a property of conventional lead solder (as with any metal), the point at which stress fatigue can occur is above stress levels normally experienced. Lead-free solder, on the other hand, will fail no matter how low the voltage level.