Solder Melting Temperature: What Is Appropriate?

Published on February 3, 2023 , Last modified on November 11, 2024
by Hommer Zhao
soldering requires understanding everything from the processes to the tools. And one crucial aspect is the solder melting temperature.

Soldering is something you can only do with experienced hands. Although it seems easy to handle, soldering requires understanding everything from the processes to the tools. And one crucial aspect is the solder melting temperature.

Knowing the entire process will help you avoid errors that can harm your working station or health. So, it’s necessary to consider the acceptable temperature for melting solder before handling any projects.

Do you have little or no experience in soldering? Don’t worry! This article will explore different solder types and their melting points.

The Basics

An anonymous man soldering a PCB

An anonymous man soldering a PCB

Generally, solders are non-ferrous metallic elements that have low melting points, often 200 degrees Celsius.

Further, solder has different composition variations, which leads to the various types we have today. However, the more common solder variants comprise tin, lead, or both.

In addition, solder can have several forms, including stick, wire, and pellet. Pellet and stick solder are ideal for solder pots, while wire variants are perfect for regular soldering. But that’s not all–you can get solder in paste, pillions, and sheet forms.

Also, you can get solder in varying colors, like copper, silver, brass, gold, or bronze, each with different properties. For example, gold solder features different shades to complement other alloys, while copper and brass variants have high melting points and brittle structures.

What Are the Types of Soldiers and Their Melting Points?

Soldering iron and solder joints

Soldering iron and solder joints

Here are the various types of solder with the required temperature for melting them properly.

Lead-free Solder

Although lead alloy solders reigned for years as the standard solder for electronics, there were many reports of health-related issues. Hence, manufacturers developed lead-free variations for safety purposes.

In truth, most companies limited the amount of lead in any component to 0.1%. And the 96.5/3/0.5 alloy was the most popular lead-free option. The variants comprised 0.5 percent copper, 3 percent silver, and 96.5% tin.

While they’re health-risk-free, lead-free solders are more expensive than other types. 

However, this variant creates brittle but stronger solder joints. And they only melt at higher temperatures. As a result, you’ll need at least 230 degrees Celsius to melt lead-free solders.

50/50 Solder

You can get this solder from a 50% combination of lead and 50% tin. Further, it’s vital to note that this solder type is not the best option for electronics. But it works great for plumbing jobs. Additionally, 50/50 solders have low flexibility and high melting points.

60/40 Solder

These solders have 60 percent tin and 40 percent lead content. Interestingly, cracks won’t happen easily, even if the joint moves frequently during cooling. And it’s because they have incredibly soft features.

In addition, 60/40 solder has a 190 degrees Celsius melting point–but it depends on the composition. Overall, we recommend using at least 300 degrees Celsius.

63/37 Solder

63/37 stands for 63 percent tin and 37 percent lead. One significant benefit of this solder type is its eutectic composition. In other words, 63/37 soldiers are easy to work with as they have fewer chances of creating bad joints.

However, it’s a pretty expensive option compared to its non-eutectic counterparts. Also, its melting point is 183 degrees Celcius. 

Note: The Zinc content in your solder determines its melting point. So, higher zinc contents translate to lower melting temperatures and vice versa.

Also, you won’t find any standards for accurate solder melting points because all manufacturers offer their specifications.

Your Soldering Iron is also Important

Soldering iron applying solder

Soldering iron applying solder

Soldering irons are your channels for releasing specific temperature amounts to melt solder. As a result, you must consider the different temperature designs before choosing your tool and solder.

Usually, soldering irons have three temperature designs, including:

  • Manual designs: These types don’t offer temperature control designs. But they’re less expensive and work better for household soldering projects.
  • Soldering stations: Soldering stations are advanced variants comprising soldering irons and benchtop control units. Also, they are the most expensive.
  • Temperature-controlled designs: These soldering irons allow you to keep the tip at the proper temperature. However, they are also quite pricey.

Rounding Up

When soldering, it’s crucial to check your working temperature periodically. It helps you avoid soldering at low temperatures or having damages from overheating, reducing the soldering tip’s life.

Thankfully, you don’t have to guess your soldering tip’s temperature. Instead, various equipment is available to help you get accurate measurements, like the TID-A digital thermometer and TIA-A thermometer.

Do you have any questions on this topic? Feel free to contact us, and we’ll be happy to help.

Avatar photo
Hommer Zhao
Hi, I'm Hommer Zhao, the founder and Chief Editor at WellPCB. With extensive experience in the PCB industry, I oversee all content to ensure it meets the highest standards of accuracy and insight. We proudly serve over 4,000 customers globally. For inquiries or more information, don't hesitate to reach out. Your satisfaction is my top priority!