59

The weld deposit composition, with a formula of 59% Ni-23% Cr-16% Mo, has been specifically designed to match the specifications of alloy 59. This high molybdenum (Mo) content is similar to that of alloys C276 and C4, but the operating capabilities in a wide range of oxidizing environments are considerably enhanced by increasing the chromium (Cr) percentage to 23% in alloy 59. The overall composition surpasses the level generally found in alloy C22, making it suitable for welds of this group of alloys. Alloy 59 consumables also offer a weld metal free from niobium (Nb), characterized by considerable strength and toughness, ideal for dissimilar welds in superaustenitic and superduplex stainless steels or in combinations of these with nickel-based alloys. Applications of alloy 59 in aggressive corrosive environments include flue gas desulfurization (FGD) scrubbers, digesters and equipment for paper manufacturing, chemical process plants, corrosion-resistant linings, and extreme offshore and petrochemical scenarios. No preheating is necessary; a heat input of less than 1 kJ/mm and a maximum interpass temperature of 100 °C are optimal conditions to minimize the formation of precipitates that could compromise the corrosion resistance and ductility of the weld metal.

Ni-23%Cr-16%Mo alloy commonly known as alloy 59.

Solid-solution strengthened high nickel austenite, with some micro segregation typical of as deposited weld metal.

Dissimilar joints between any combination of the listed alloys and dissimilar joints between them and superduplex stainless steels.

• EN W.Nr.: 2.4605 (NiCr23Mo16Al), 2.4602 (NiCr21Mo14W), 2.4811, 2.4836 (NiCr20Mo15), 2.4697 (G-NiCr20Mo15)
• ASTM: A494 gr. CX2MW
• UNS: N06059, N06022, S32654, S31254, S34565
• PROPRIETARY: Nicrofer 5923hMo, 5621hMoW (VDM), Inconel®Alloy 686 (Special Metals), Hastelloy® Alloy C-2000, C22 (Haynes International Inc), 654SMO (Outokumpu), Uranus B66 (Usinor Industeel)