On the determination of stress profiles in expanded austenite by grazing incidence X-ray diffraction and successive layer removal. (1st August 2015)

• Record Type: Journal Article
• Authors: Fernandes, Frederico A.P.; Christiansen, Thomas L.; Winther, Grethe; Somers, Marcel A.J.
• Is Part Of: Acta materialia. Volume 94(2015)
• Page Start: 271
• Page End: 280
• Publication Date: 2015-08-01
• Subjects: Low temperature surface hardening -- Gas nitriding -- Expanded austenite -- X-ray diffraction -- Stress analysis; Materials -- Periodicals; Materials science -- Periodicals; Materials -- Mechanical properties -- Periodicals; Metallurgy -- Periodicals; Chemistry, Inorganic -- Periodicals; 620.112
• DOI: 10.1016/j.actamat.2015.04.040
• Languages: English
• ISSNs: 1359-6454

Abstract

Abstract: Surface layers of expanded austenite resulting from nitriding typically exhibit large gradients in residual stress and composition. Evaluation of residual-stress profiles is explored by means of grazing incidence X-ray diffraction (GI-XRD), probing shallow depths, combined with successive layer removal. Several factors complicating the stress determination are analysed and discussed: (1) ghost stresses arising from a small variation in the shallow information depths probed with GI-XRD, (2) selection of the grain interaction model used to calculate the X-ray elastic constants for conversion of lattice strains into residual stress and (3) the composition dependence of these elastic constants.