PCBs are one of the most important things in an electronics project. Furthermore, when talking about PCBs, there will be some components embedded on it. To embed these components such as capacitors, resistors on a PCB, you’ll have to solder them. In this article, you’ll learn about solder, types of solder, and a quick comparison and contrast of lead solder vs lead-free solder.
What is solder in PCB?
Before going through lead vs. lead-free solder of PCB soldering, you must know what exactly is solder. Solder is a metal, that comes in the form of a wire. You need to use a soldering iron to melt it down and place it on the intersection of the component pin in the PCB vias. When you take away your soldering iron, the solder will cure and harden to make a strong bond.
That’ll keep your electronic component from coming off the PCB. To make your solder strong, you can use solder flux that reacts with the chemicals in the solder. Solder is gray in color.
What are the types of solders?
1.Resin-core solder: The inner core of the wire has a resin that acts as a mild flux.
2.Acid-core solder: The hollow core of the wire has acid that acts as an aggressive flux.
3.Solid-core solder: It is a standard metal alloy with no hollow core and needs flux to be added separately.
4.Silver-based solder: This metal alloy contains a higher percentage of silver which increases its electrical conductivity and strength and is used where strong and reliable joints are required.
5.Indium-based solder: This soldering alloy is known for its high ductility and low melting point and is used when bonding electronic components with different thermal expansion coefficients.
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What are lead solder vs lead-free solder made of?
Lead vs lead-free solders have different metals in the solder wire. A lead solder, as the name suggests is primarily made of lead. On the other hand, a lead-free solder consists of tin, copper, and other soft metals. Some lead-free variants also have precious metals such as silver. Lead-free solder always has eco-friendly metals that do no harm to humans. Lead solders will, however, have a high quantity of lead, making it toxic.
Lead Solder – Pros and Cons
Benefits of lead solder
●Lead solders offer incredible performance, making it ideal for use by advanced engineers.
●Lead solder has a low melting point, which is why it becomes compatible with low-power solder irons. Lead solder will work perfectly with a 25W soldering iron too.
●When cured, lead solder will withstand strong shocks and vibrations, keeping connections tight.
Drawbacks of lead solder
●When molten, lead solder will generate toxic fumes that are very harmful. Engineers who manually solder are at a high risk of inhaling this toxic gas that can cause asthma.
●Eyes can get irritated easily when working with lead solder for a long time which can cause vision impairment.
●If a lead solder has an acid core, it’ll be even more harmful to the skin.
●The strength of bonds created by lead solders can make it difficult to remove a component later during repair.
●In rare cases, a lead solder can damage a PCB, especially if the PCB is made of low-quality raw materials.
Lead-free solder – Pros and Cons
Benefits of lead-free solder
●Certain combinations of metals to create a lead-free solder can actually create stronger joints than a lead solder, making it a better choice to achieve anti-shock and anti-vibration connections.
●A lead-free solder is a better choice if you want to comply with government restrictions. There’s no government policy in any country that opposes the use of lead-free solders.
●Lead-free solders do not leave damage to the circuit board when soldering.
●They’re perfectly compatible with soldering flux, which helps create an even stronger bond.
Drawbacks of lead-free solder
●Due to high melting points, lead-free solder becomes difficult to work with.
●Lead-free solders can be expensive due to precious metals in it.
●Tin whiskers are the most annoying spike-like structures that get formed after curing for no good reason. Even scientists are unable to find out why tin whiskers are formed. But tin whiskers weaken the joints and make it irritating for the PCB manufacturers to eliminate them.
Lead Solder vs Lead-free Solder – What’s the difference
Let us compare and contrast lead solder vs. lead-free solder.
1.Physical Differences
Lead solders appear shinier than the lead-free ones due to presence of lead that reflects light rays, making a lead solder appear shinier.
2.Performance Differences
A lead solder performs better in terms of electrical and mechanical properties. That’s why experienced engineers prefer lead solder over lead-free one.
3.Cost Differences
Lead is a cheaper metal, making lead solder a cheaper choice over a lead-free one. Lead-free solders expensive metals such as tin, silver, etc. that raises its overall cost.
Factors to consider when switching to lead-free solder
●When switching to lead-free solder, always consider whether your project is suited for a lead-free solder in terms of electrical and mechanical performance.
●You’ll have to increase your budget to switch to lead-free solder.
●Lead-free solder ain’t easily available in the local retail market, so you’ll have to make extra effort in finding a supplier.
Which solders should be used – Lead solder vs Lead-free solder?
If possible, consider lead-free solder in the first place. Lead-free solder has several notable advantages over lead solder, making it a better choice overall.
●Consider lead solder if performance matters in your project.
●Some countries have strict regulations for the use of lead solders. To sell your products in such countries, you’ll have to switch to lead-free solder.
Conclusion
By now you’ve understood the key differences between lead solder vs lead-free solder. You’ve also got an idea of which one to choose and why. If you have any electronics project in mind and aren’t sure about which solder to use, drop all your worries to IBE Electronics, who’s a master in using lead and lead-free solders according to the needs. IBE Electronics will ensure that you don’t run into any trouble on use of lead or lead-free solders, and IBE Electronics will automatically decide which type of solder is best for you.
- A lead solder, as the name suggests is primarily made of lead.
- A lead-free solder consists of tin, copper, and other soft metals.
- When molten, lead solder will generate toxic fumes that are very harmful.
- The strength of bonds created by lead solder can make it difficult to remove a component later during repair.
- If a lead solder has an acid core, it’ll be even more harmful to the skin.
●For materials, it is more healthy than lead solder.
●Lead-free solders do not leave damage to the circuit board when soldering.
●They’re perfectly compatible with soldering flux, which helps create an even stronger bond.
