C276

The deposited weld replicates the composition of parent alloy C276, comprising Ni-15%Cr-16%Mo-4%W-5%Fe. Precise control over C and Si levels is implemented to minimize carbide and intermetallic phase precipitates. While cast versions may have higher carbon and silicon content, repair welds typically undergo solution treatment for optimum corrosion resistance. Alloy C276 exhibits high resistance to corrosion in a broad range of acids and salts under oxidizing and reducing conditions, including hydrochloric and hydrofluoric acids, hypochlorites, chlorides, wet chlorine gas, sulphuric, phosphoric, and various organic acids. Noteworthy is its exceptional resistance to crevice corrosion, pitting in seawater (surpassing alloy 62), and chloride-induced stress corrosion cracking. With excellent properties extending to below -196°C, Alloy C276 finds applications in welding 5-9%Ni cryogenic installations. Its versatile use includes pumps, valves, pipework, and vessels in aggressive chemical plant environments, as well as equipment for flue gas desulphurization and critical offshore oil and gas production equipment. Importantly, preheating is unnecessary, and it is advisable to keep the interpass temperature below 100°C, with a restricted heat input to 1.5 kJ/mm.

Alloy C276 is a Ni-15%Cr-16%Mo-4%W-5%Fe nickel base alloy.

In the as-welded condition the weld metal consists of austenite with some carbides.

EN W.Nr.: 2.4819 (NiMo16Cr15W), 2.4883 (G-NiMo16Cr).
ASTM: A494 CW-12MW, A743/A744 CW-12M.
UNS: N10276.
PROPRIETARY: Hastelloy® Alloy C-276 (Haynes International Inc), Inconel® Alloy C-276 (Special Metals), Nicrofer 5716hMoW (VDM).