TIG welding uses tungsten electrode and Argon gas for clean welds. Protective eyewear, fire-resistant clothing, and helmet required. Thoriated electrodes are mildly radioactive, use dust mask
Butt welding joins metal pieces end-to-end using heating and fusing. Common types include GTAW, GMAW, SMAW, and FCAW. Requires accurate metal alignment and proper groove preparation
Most common welding process in US, used for over half of all welding. Uses flux-covered consumable electrode with protective gas shield. Simple and versatile but has lower deposition rate than other processes
ERW joins metal parts by heating them with electric current. Molten metal pools form at points of electrical resistance. Process uses copper electrodes with clamping pressure. Current ranges from 100 to 100,000 A
Two metal pieces are joined end-to-end without overlap. Surfaces must be on same plane for weld metal to remain within planes. Can be automated or hand-done on steel or copper with brazing
Contains 12% Cr for moderate corrosion resistance. Magnetic martensitic stainless steel with good mechanical properties. Used in steam turbines, jet engines and gas turbines. Type 420 is high-carbon version with higher strength