Comparison of lead free solders and leaded solders
Comparison of lead free solders and leaded solders
In the solder industry, the mostly mentioned types or the major classifications of the solders will be Lead Free Solders & Leaded Solders. This is determined by whether the solder alloy contains lead or not. Traditional solders will be tin & lead alloyed together, generally lead is no more than 37% and remaining is tin. While lead free solders are lead free (Pb<1000mg/kg), majorly is composed of Tin (Sn), Silver (Ag) and Copper (Cu).
Types of Leaded Solder Alloys:
Sn63Pb37
Sn60Pb40
Sn50Pb50
Sn40Pb60
Sn30Pb70
Sn20Pb80
Sn10Pb90
Types of Lead Free Solder Alloys:
Sn96.5Ag3.0Cu0.5
Sn99Ag0.3Cu0.7
Sn99.3Cu0.7
Major differences of Lead Free Solders & Leaded Solders:
1. Lead is one of the heavy metal and not good for health, that's why lead free solders were invented. So for some applications whereas ROHS & REACH standard must be applied, only lead free solder alloys can be used.
2. Melting point: Tin Lead alloy has a much lower melting point at 183℃ comparing to lead free solder 217℃. That means for some components that is temperature sensitive, the tin lead alloy is more ideal to be used for soldering purpose because the working temperature is lower.
3. Lead will help the solder to perform better and making it much easier to melt and joint, giving the solder a good wetting and fluidity property, in this aspect it's better than lead free solders.
4. Due to melting point of lead free solder alloys are higher, so solderjoint of lead free type is more firm than leaded solders.
5. Cost wise, leaded solders are much cheaper comparing to lead free ones. Because lead is just about 1/10 of tin price, that makes leaded solder cheaper, while some lead free solders contain silver which are so much more expensive than tin.
As a coin has two sides, so just choose the most proper one, it doesn't have to the most expensive one.
Check below to be directed to the product page of different types: