Which of the following materials can be welded using the GMAW process?

The GMAW (Gas Metal Arc Welding) process, also known as MIG (Metal Inert Gas) welding, is versatile and capable of welding a wide range of materials, including stainless steel, cast iron, and aluminum.

When welding stainless steel, GMAW can provide excellent results due to its ability to create strong joints while maintaining good corrosion resistance. The use of different filler wires tailored for stainless steel enhances the quality of the weld.

For cast iron, while it can be a challenge due to its brittleness and tendency to crack, GMAW can still be effectively used with the right techniques and filler materials. Preheating may be required to minimize thermal shock during the welding process.

With aluminum, GMAW is particularly effective. The process allows for clean, porosity-free welds, especially when using argon-rich shielding gases that protect the molten weld pool from atmospheric contamination.

The flexibility of GMAW makes it suitable for all these materials, thus making the option that encompasses all of them the correct choice.