Haynes Hastelloy C-4 description: HASTELLOY C-4 coated electrodes are used for the shielded metal arc welding of C-4 alloy. The weld metal has good resistance to a wide range of corrosive attack including contaminated mineral acids and chlorine contaminated media. In addition, the electrodes can be used for the overlay and cladding of carbon and stainless steels where enhanced corrosion resistance is required. The coating is designed for great operability, especially in out-of-position welding.