657M

Filler metal classified under this classification is employed for overlay cladding on ferrous materials in high-temperature applications. Moreover, it proves effective in welding nickel-chromium-iron alloy to itself and to steels through the GTAW and GMAW processes. Welds created with this composition exhibit exceptional resistance to high-temperature oxidation, carburization, and sulfidation. Its functional versatility extends to operations in heat exchangers, piping, vessels, including evaporators, in offshore, marine, chemical, petrochemical, and power engineering industries. Notably, DAIKO 657M wire, is tailored for customization across a diverse range of components in oil-fired furnaces and boilers. These components encompass tube sheets, tube hangers, supports, and spacers in ships, power stations, and refineries within numerous petrochemical plants.

The nominal composition (wt. %) of filler metal of this classification is 60 Ni, 37.5 Cr, 0.95 Al, and 0.6 Nb plus Ta.

Austenitic.

For cladding of ferrous materials used in high temperature applications, and the welding of nickel-chromium-iron alloy to itself, and to steels.
ASTM: B163, B166, B167, B168.
UNS: N06690, N08810.
PROPRIETARY: Incoloy® 671 (Special Metals), Incoloy® 800H (Special Metals).

To ensure the cleanliness of the base metal in nickel-base alloy welding or heating, be vigilant about substances like oil, grease, paint, lubricants, marking pencils, temperature-indicating materials, threading compounds, and similar items. These materials often contain S or Pb, posing a risk of cracking (embrittlement) in both the base and weld metal during these processes. Generally, preheating nickel alloys is unnecessary unless required to bring the metal in the welding area to room temperature or a standard shop temperature to prevent moisture condensation. Adhere to a low heat input, capped at a maximum of 1.5 kJ/mm, and comply with an interpass temperature limit of 150°C. In most cases, solid solution nickel alloys don't require post-weld heat treatment for corrosion-resisting service, while precipitation-hardening alloys need heat treatment after welding for full strength.