Published online by Cambridge University Press: 06 March 2019
Conventional X-ray stress analysis is based on the so called "linear sin2ψ" law and yields average two axial stresses in the irradiated surface layer of polycrystalline specimens. Three examples are given in this paper where either strong deviations from the linear law are observed due to stress gradients or where the linear law yields wrong results because of three axial stresses. Special experimental techniques are described and formalisms are given for the evaluation of the corresponding stress fields which are in the described cases more complicated than usual.