Metrode TUF-MET-1NIB description: For welding higher strength steel structures where PWHT is impracticable so that welds must possess an appropriate degree of toughness and crack resistance. The addition of about 1%Ni promotes microstructural refinement, with improved tolerance to procedural variations compared to plain CMn weld metal. Nickel also increases atmospheric weathering resistance and improves electrochemical balance between weld and base metal, thus minimising preferential weld area corrosion in marine environments. For offshore oilfield sour service, a maximum of 1.0%Ni is commonly required (NACE MR0175).