Question

this part supplies shielding gas to protect the molten metal from the atmosphere. nozzle diffuser liner contact tip

Explanation:

In welding processes, the nozzle is the component that supplies shielding gas. Its main function is to direct and release the shielding gas around the welding area. This gas creates a protective barrier, preventing the molten metal from reacting with the oxygen and nitrogen in the atmosphere. A diffuser (used to make gas flow more uniform), liner (part of wire - feeding mechanism), and contact tip (for electrical contact with the wire) do not have the primary function of supplying shielding gas.

Answer:

Nozzle