| Some problems arise in the case of residual stresses measurements by X- ray diffraction technique when analyzed stress state is characterized by strong gradient on the surface of a material. These problems include the fact that linear dependence of the diffraction angle θ φ,ψ =f(sin2ψ) becomes nonlinear. Besides, there is broadening of diffraction line caused by surface stress gradient. If the first problem makes difficulty to calculate the value of mechanical stresses, the second provides an opportunity to find the relationship between the diffraction line width and stress gradient parameters. Analysis of nonlinear displacement with broadening of diffraction line and development of methodology of stress determination with strong gradient is the objective of this paper. |
full paper (pdf, 224 Kb)