Comparative studies of elastic and plastic strain in metals

Elastic and plastic strain inhomogeneities in polycrystalline materials (titanium, iron, copper) with different polycrystalline structure are studied experimentally and theoretically. Results of the study obtained by application of the finite element method and measurement of the strain on the small base of 10 μm are presented. The presence of inter- and intragranular inhomogeneity of stresses and strain in the elastic region whose level depends on the anisotropy of elastic properties is shown. The highest value of inhomogeneity is noted in the boundary regions. It is established that inhomogeneity of plastic strain for the studied polycrystals is essentially higher than inhomogeneity of elastic strain which is specified by the difference in mechanisms of elastic and plastic strain, by different level of elastic and plastic anisotropy as well as by peculiarities in interaction of particular crystallites (grains) in the polycrystal assotiated with it