Mechanical properties such as strength, ductility and fracture toughness are strongly dependent on the residual stresses present in a material. X-ray diffraction techniques enable both the determination of macroscopic residual stresses (1st order stresses) as well as the integral measurement of microscopic residual stresses (2nd and 3rd order stresses).
For local analysis of microscopic residual stresses (e.g. inside a particular grain or within nm-sized thin films) the bending beam (interlayer removal (ILR)) method and the slit method are applied.
The bending beam method is used for calculation of the residual stresses in individual layers of multilayer systems by means of the beam deflection. Using the slit method requires a FIB-cut into the surface inducing a stress relaxation. The subsequent application of image correlation enables the estimation of the magnitude of compressive and tensile stresses in the surrounding area.