Line pipes internally clad by nickel alloy are being considered as steel catenary risers when exploitation of corrosive oils is envisaged and corrosion-fatigue failures are possible. The presence of the Ni alloy as internal clad requires a matching filler metal and, consequently, the girth welds are dissimilar joints. Although these types of welds are widely used in the petroleum industry their fracture toughness are not well documented. Of particular concern is the formation of hard zones in HAZ which are usually associated with low fracture toughness. Joints of API X-60 pipes welded using NiCrMo-3 consumables were CTOD tested at 0°C. Results consistently revealed high fracture toughness values for the weld metal. The HAZ-FL, on the other hand, presented lower values and they were significantly dispersed. Microstructural and fractographic analyses revealed that low values of toughness are associated with local brittle zones (LBZ) mainly IRCGHAZ. The fracture of the specimen that presented the lowest toughness initiated in a partially mixed zone containing hard martensite.

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