The use of high quantities of lead in consumer products over an extended period causes harmful effects to the environment and people. Currently, companies have shifted to lead-free soldering to support their social responsibility efforts of protecting the environment. Thus, it is crucial to learn how lead-free solder compares with leaded solder and examine the better option for use.
Melting Point
Lead-free solder has higher melting point than lead solder. Lead solder has a melting point of 1830C, while lead-free solder has a melting point of 2170C. Now, these are the effects of the higher melting point of lead-free solder:
- The higher temperature of lead-free soldering oxidizes the solder quickly compared to the lower temperature of lead soldering.
- Like those containing plastic packages and electronic capacitors, some components are negatively affected by the high soldering temperature of lead-free solder.
- The high temperature of lead-free solder comes with significant component stress; therefore, low dielectric components are more vulnerable to failures.
- Lead-free solder components have several soldering surfaces. Companies often use tin on such surfaces because it is cost-effective. However, the tin generates a small oxidation coat on the outside that can lead to electroplating.
Eutectic
Manufacturers valued the use of tin and lead because it formed a eutectic mixture. In other words, the lead and tin composition have a lower temperature than the individual metals’ temperatures. Although the electronic manufacturing world has not managed to discover another eutectic metal combination, it has invented a lead-free soldering technique that works well.
Health Concerns
Companies sensitive to environmental conservation state the poisonous nature of lead as their main reason for embracing lead-free soldering. Lead can indeed accumulate in the human body even from small prolonged exposures. Furthermore, lead can quickly enter your body through the skin, mouth, or nose. The paint and gasoline sectors have all gone lead-free. However, solder is among the remaining products that still use it.
In an industry experiencing high lead emission, workers are more vulnerable to the dangers of lead as they can quickly inhale it or get it by touching contaminated surfaces. Remember, lead is more dangerous to children. Therefore, take these health concerns seriously wherever you are using lead solder.
Cost
Leaded solder is cost-effective than lead-free solders. This is because lead is barely a tenth of the tin price, making leaded solder easily affordable. Furthermore, some manufacturers replace tin with silver in lead-free solders, making them even more expensive.
Wettability
Lead-free Solder has Poor Wettability than Leaded Solder. Low wettability makes the solder joint function ineffectively in meeting the demands of self-regulation ability, tensile power, and shear capacity. Consequently, low wettability causes a high rejection rate of solder joints, especially when you fail to conduct adjustments to cater to this shortcoming.
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