Items, that are used to fill the welding joint and protect the weld pool from atmospheric contamination fall under the category of welding consumables.
Welding electrodes are classified into two types, based on their work. Consumable and Non-consumable electrodes. Consumable electrodes are fused completely and fill the joints but non-consumable electrodes are used with high melting point metals. Basically non-consumable electrodes using in welding operation are tungsten and its alloys and graphite. See Detail… Welding Electrodes
Flux is used to protect by covering molten metal from atmospheric contamination. Various types of fluxes are used especially in the FCAW process.
Various types of Shielding Gases are used to protect the weld pool from atmospheric contamination in fusion welding.