Influence of substructure inhomogeneity on the anisotropy of physical properties of textured materials

Abstract

Calculation of the physical properties anisotropy is based on single crystal properties and information about material texture, i.e. orientation distribution function (ODF). At the same time, the grains of different orientations are known to have different substructure parameters including the lattice distortion and microstrains. Determination of these parameters is possible with the X-ray method of Generalized Pole Figures (GPF), which consists of registration of the whole X-ray reflection profile under the pole figure recording. As a result, one can obtain the FWHMs of X-ray line profiles and microstrains distributed on the stereographic projection. Despite the observable equilibrium of tensile and compressive microstrains of differently oriented grains within the studied material volume, they can affect the product properties anisotropy. In this study the calculation method for elastic properties and thermal expansion coefficients taking into account substructure inhomogeneity is offered on the basis of elastic energy minimization. Its efficiency is demonstrated for the samples of zirconium alloys.