The idea of fusing metals goes back thousands of years, with the first known examples dating back to the bronze age, circa 3000 BC.

While it has seen various stages of evolution since then, welding has cemented its place as one of the most crucial components of all manufacturing industries.

As of 2020, the global welding market was valued at $20.23 billion, and is expected to grow to $28.66 billion by 2028. The U.S. alone employs nearly 600,000 welders in 2023.

Clearly, welding is a popular profession. But how many of us understand precisely how it works? To get behind some of the more complex welding concepts, we’ve brought together a group of nexAir experts to share their KnowHow.

Let’s dive right in.

The Science Behind Welding 

For the completely unaware, welding refers to the process of fusing together two materials — usually metal. The two metals are joined together using a filler material. The result is a much stronger and longer-lasting joint than those produced by other processes generally used to join metals, such as soldering or brazing.

To understand a bit more about the actual process, let’s take the example of the most popular welding method, arc welding. As the name implies, through this process, a welder creates an electric arc to melt both metals and create a joint.

This arc, which comes from an AC or DC power supply, is very hot — over 6000 degrees Fahrenheit — melts the metals and fuses together the two pieces. The filler is consistently fed into the welding joint for uniformity.

Other welding types follow a similar principle but differ slightly in process. Gas welding, for instance, relies on a steady supply of gas, which is funneled through a stick and ignited to create a high-temperature flame. The most recent of all these innovations, laser welding, uses high-energy beams to fuse materials. 

The Role of Gas in Welding  

Some processes, such as gas metal Arc welding or Tungsten arc welding, also use shielding gases.

This external gas supply mainly serves a couple of purposes: For one, it acts as a layer of protection for the molten pool, preventing it from being contaminated by debris and atmospheric gases, which can affect the quality of the weld.

At the same time, it enables the transfer of filler material, improving efficiency and cooling the welding gun. Shielding gases are generally inert to ensure they don’t react with the molten pool. The most common shielding gases include argon or helium.

Other gases like nitrogen aren’t necessarily recommended as shielding gases but can still be used for other purposes, such as corrosion resistance. 

Forge Forward with nexAir’s Expertise

The basic concept of welding as a way to fuse two metals together seems easy enough to understand. But with dozens of processes, several blends of gases, and constant evolution, the science behind welding can take years to grasp.

As one of the leading suppliers of welding supplies and KnowHow across the Southeast, nexAir understands how complicated welding can be. Since the 1940s, we have attracted some of the most knowledgeable talents from across the country to help companies Forge Forward productively and with the right technology.

Get in touch with us to learn more about the various welding processes.