What is the most popular ferrous metal used in welding applications?

Steel is the most popular ferrous metal used in welding applications due to its versatile properties, availability, and wide range of applications. It contains iron as its primary element, which classifies it as a ferrous metal. Steel can be alloyed with various elements to improve its strength, ductility, and resistance to corrosion, making it suitable for everything from construction to automotive manufacturing.

Additionally, steel's ability to be easily welded using various welding processes, including Gas Metal Arc Welding (GMAW), contributes to its popularity among fabricators and manufacturers. The ease of welding combined with the desirable mechanical properties of steel makes it the material of choice for many industrial and structural applications.

Other materials listed, such as copper, zinc, and aluminum, although useful in specific applications, do not match steel's overall prevalence and versatility in the welding industry.