TIG rod of W 25 9 4 N L / ER2594 type with intentionally added W and Cu for welding superduplex steel and equivalent steel grades such as 1.4410 / UNS S32750, 1.4507 / UNS S32550 and 1.4501 / UNS S32760. Can also be used for joints between superduplex and austenitic alloys or carbon steels. For welding of duplex type 1.4462 / UNS S32205 if extra high corrosion resistance is required. The properties of the weld metal match those of the parent metal, offering excellent resistance to stress corrosion cracking and localized corrosion in chloride containing environments. Pitting resistance is in accordance with ASTM G48A Methods A, B and E (> 40oC). Welding without filler metal (i.e. TIG-dressing) is not allowed since the ferrite content will increase drastically and both mechanical and corrosion properties will be negatively affected.