Is solder paste toxic? What you need to know

Is solder paste toxic? That is a question that receives a lot of attention today. Because solder paste is an indispensable material in the process of soldering PCB electronic components. User concerns in this regard are obvious. Follow the article below to get the correct answer to this question!

Learn about welding materials

Solder paste is an alloy of tin with other metals, usually, lead, silver, and copper mixed in certain proportions. The melting temperature of solder paste is quite low, about 90 to 450 degrees Celsius, used to bond metal surfaces together.

The characteristics of solder paste are silver luster, easy to melt, and very difficult to oxidize and corrode. Solder paste is used together with tin solder and flux to create a durable, beautiful weld over time.

Tin-Solder is now produced in many forms such as solder wire, solder bars, and solder paste. Depending on the needs of use customers choose the appropriate welding method.

How many types of solder paste are there today?

Leaded solder paste (Lead) is currently classified into two main types, leaded solder paste, and lead-free solder paste.

Leaded solder paste

Leaded solder paste is a solder made from mainly 2 metals, Tin and Lead, which are also combined together in certain proportions. Based on the mixing ratio, lead solder will be divided into 2 common types:

Ratio 63/37 with 63% Tin and 37%: This ratio is standard when soldering produces eutectic mixtures possessing many special properties such as having the lowest melting point of all tin alloys. lead, beautiful solder joints, and more glossy.

Ratio 60/40 with 60% Tin and 40% Lead: This ratio requires a higher temperature to melt, so it is easy to affect components, especially since the solder joint is not as beautiful as 63/37.

The advantage of leaded solder paste is that you can clean the solder flakes after soldering easily. Because lead is resistant to freezing for a certain time.

Lead-free solder paste

Lead-free solder paste is a solder paste that can be made from 100% pure tin. Or it can be made from tin combined with silver and copper metals in the ratio of 96.5% Tin, 3% Silver, and 0.5% Copper. Although this type of welding requires a higher welding temperature (from 340 – 370 degrees Celsius), it possesses many outstanding properties such as good flow rate and fluidity, and bright welds. and more beautiful is the ability to conduct electricity, heat conduction remains the same. Not only that, the joint after soldering is also very hard and more durable than those containing lead.

Answer the question: Is solder paste tin toxic?

To answer the question of whether solder paste is toxic, you need to know that solder paste is currently divided into 2 types, lead-based and lead-free. Any solder paste containing lead will affect human health. When soldering, dust is generated in the molten lead-containing compound, which if inhaled will be extremely harmful to the body. Specifically, when welding fumes enter the human body, it will cause the following phenomena:

Headache, Dizziness, Nausea

Allergies, dermatitis

Shortness of breath

The worst is death

However, especially with lead-free solder paste ones, this disadvantage will be overcome. Lead-free solder paste is very safe for the welder as well as the user, protecting the health and life of the customer. In particular, lead-free solder paste is not only safe but also very versatile, with a very reasonable price, so factories and enterprises are very fond of producing this material in assembling electronic components.

Above are the answers to the question of whether solder is toxic. Hopefully, through this article, you have understood more about this material. If you have any questions, do not hesitate to contact Thetech for timely advice and support!