X-ray diffraction analysis of intergranular strains in cold-rolled ultra high purity iron

Intergranular strain and the associated stored energy were investigated by X-ray diffraction in two texture components of cold-rolled ultra high purity (UHP) iron. Laue peaks were measured on plastically deformed samples and the center of the lines was compared with reference peaks recorded from a well-annealed powder sample of the same material. The intergranular stored energy as evaluated from the residual strain tensor was found to be much higher for the [1 1 0](0 0 1) α fibre component than for the [1 2 1](1−1 1) γ fibre component. Experimental results show that the soft α grains of the polycrystal, containing fewer dislocations, are more strained by their surrounding than hard γ grains with more dislocations. Generally intergranular strains decrease with deformation.