Arc welding

Arc welding uses electricity as the power source to create an electric arc between an electrode and the base materials to melt the base materials and cause them to join as the metal solidifies. The region being welded is sometimes protected by an inert gas such as argon, known as a shielding gas. Arc welding can create joints by introducing additional metal, called filler metal or by simply melting the parent metals, called autogenous welding.