This electrode is also known as alloy 21. The flux is a rutile type made on a fully alloyed core wire. Cobalt based electrode designed on a fully alloyed core wire to combat all four elements of wear, i.e. heat, impact, corrosion and abrasion. Most suitable of cobalt range where toughness is the most predominant of the four elements of wear. Excellent for rebuilding corners with minimum base metal dilution. Has ability to overlay extensive areas without cracking. Designed specifically for use as a forging die material. Because of its low carbon content, the electrode has excellent resistance to thermal and mechanical shock. The electrode deposits a high alloyed cobalt base weld metal with 0.3% carbon. Welds are machinable. The suggested usages are in iron and steel industries or any industry where heat, corrosion and abrasion occur concurrently, for such items as steel mill rolls, valves seat inlays, hot working dies and tools, hot shearing blades, tongs etc
The electrode main advantages are: - High temperature strength and ductile, resists thermal shock. Tough-impact resistant. Highly ductile-resists weld cracking (without any preheat). High resistance to corrosion, oxidation, sulphidation. Hardness 30 HRC as deposited, increases to 50 HRC with work hardening. High resistance to cavitation-erosion.