Microstructural and Mechanical Characterization of the Transition Zone of 9%Ni Steel Cladded with Ni-Based Superalloy 625 by GTAW-HW

• Published in: Metals (Basel ) Vol. 8; no. 12; p. 1007
• Main Authors: Cipriano Farias, Francisco Werley, Payão Filho, João da Cruz, Barreto de Azevedo, Luiz Maurício
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.12.2018
• Subjects: Allotropic transformation; Bend tests; Chemical elements; cladding; CO2 injection unit; Corrosion; corrosion resistant alloy; Crack propagation; cryogenic steel; Crystallography; Diamond pyramid hardness; dissimilar transition zone; Electron backscatter diffraction; electron backscatter diffraction (EBSD); Gas industry; Gas tungsten arc welding; Gases; Hydrogen embrittlement; Hydrogen sulfide; interface of dissimilar metals; Mechanical properties; Microstructure; Nickel base alloys; Nickel steels; Peninsulas; Solidification; Steel pipes; Stress cracking; Substrates; Superalloys; type II boundary; weld overlay; weldments; United States > US

9%Ni steel was recently used for the first time in the field of injection unit (IU) for the injection of CO2 into oil wells. Because such steels are operated in H2S medium and are susceptible to sulfide stress cracking, their pipes are cladded with Ni-based superalloy 625 by using gas tungsten arc w...