Coelho, Luís Manuel de JesusBatista, A. C.Nobre, J. P.Marques, M. J.2015-01-272015-01-272011Coelho, L.; Batista, A. C.; Nobre, J. P.; Marques, M. J.Evaluation of stress-strain behavior of surface treated steels by X-ray diffraction, Central European Journal of Engineering, 2, 1, 91-95, 2011.1896-1541http://hdl.handle.net/10400.8/1275X-ray diffraction assisted four-point bending method (XRDABM) enables to analyze the evolution of surface stress with the strain during bending of specimens. This experimental methodology was used to characterize the stressstrain behavior of two plasma nitriding steels, DIN 40 Cr Mn Mo 7 and DIN 32 Cr Mo V 13, with gradients of mechanical properties across the surface layers, allowing the characterization of the in-depth evolution of the local yield strength in the nitrided layer. The results show a significantly increase of the yield strength of the nitride layers and a good agreement between the in-depth evolution of the yield strength and the XRD peak breadth for the two nitrided steels.engX-Ray ciffractionFour-point-bending-methodNitrided steelsSurface treated layersStress-strain behaviorYield strengthjournal article2015-01-2310.2478/s13531-011-0051-4