A new development in the determination of residual stresses in thin surface layers and coatings is presented. The procedure, based on the grazing‐incidence X‐ray diffraction geometry (referred to here as the `g‐sin2 ψ' geometry), enables non‐destructive measurement at a chosen depth below the sample surface. The penetration depth of the X‐ray radiation is well defined and does not change during the experiment. The method is particularly useful for the analysis of non‐uniform stresses in near‐surface layers. The g‐sin2 ψ geometry was applied for measurements of the residual stresses in TiN coatings. Anisotropic diffraction elastic constants of textured material were used to determine the stress value from the measured lattice strains. A new method of data treatment enables reference‐free measurements of residual stresses.

The textures of cold-rolled AISI 304 austenitic steel were the object of the investigations. The austenite steel was deformed by cold-rolling to 20, 40 and 70% reduction. A significant amount of martensite, formed due to the strain induced (γ®a’) transformation, was detected in the deformed structure by applying magnetic and X-ray diffraction methods. Texture analysis was performed on the basis of the orientation distribution functions (ODFs) calculated from the experimental pole figures. The texture measurements of both phases were conducted from the center layers of the cold-rolled strip. In the case of metastable austenite AISI 304 steel the texture development was very complex because three processes were proceded simultaneously during the cold-rolling, namely: plastic deformation of the austenitic g-phase, strain induced phase transformation γ®a’ and deformation of the formed a’-martensite. These processes resulted in the presence of two phases in the structure of the steel with a definite crystallographic relationship and orientation changes of both phases with increasing of the deformation. Thus, the resultant deformation texture of the investigated steels is described by the austenite and martensite texture components. The rolling texture of γ-phase describes mainly orientations from the fiber α =<110>║ND and the major components of the martensite deformation texture are orientations from the fibers α1=<110>║RD and γ ={111}║ND.

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During the test, no spallation of the external oxide scale was observed. The kinetic data showed that only the 263 alloy oxidized according to parabolic behaviour, whereas the other alloys deviated from the parabolic rate law, with time exponents of 0.4-0.6 or 0.3. Finally, cross-sectioned investigations of the exposed samples revealed that Ni-based alloys underwent extended internal oxidation, with the highest extent in HAYNES Ò 282 Ò reaching 25 lm and the lowest in HAYNES