We're going to talk about GTAW or commonly referred to TIG. GTAW is a welding process that uses gas tungsten arc welding. And one of the best ways to understand how this process works is to understand each of the letters in the acronym.

The G or gas in GTW is very important because what gas does is we want to keep oxygen away. When oxygen gets in a weld, it creates oxidization or porosity. This is always a bad thing in welding, any type of welding. So the gases that we use in GTAW are inert gases that do not react with the metal, generally argon or helium.

The T in GTAW is tungsten. Tungsten is a very special metal that has a high refractory index. What that means is that the metal won't heat up and it'll actually direct the electricity through the metal. It'll come out the other side. So a refractory metal won't heat up, but it does transfer electricity. That's why tungsten is so great for GTAW welding because we're trying to create a weld puddle without actually melting the tungsten.

Arc welding is the process of using electricity to create a weld. Now there's lots of other types of welding. There's oxy-fuel welding. There's electron beam welding. They all have a different heat source. The heat source for GTAW is arc welding, which means it's coming from electricity. The electricity put into it is usually electro negative, which means that most of the heat will be at the plate and not at the parts.

The important part of understanding welding is that welding is not gluing or consolidating or sticking. Welding means that we are actually fusing materials into a new clean homogenous weld. So what's happening is we're taking the parent metal in this case and filler metal or sometimes autogenous, which is just parent metals. And we're melting them together to create a new clean weld.