Considerable grain refinement in bulk materials is achievable through the application of severe plastic deformation. In particular, equal channel angular extrusion could be utilised for this purpose. In the current work, samples of interstitial free steel were pressed in air at room temperature. The tests were performed with 120° die channel angle up to 4 passes. Route BC was utilised. The specimens were characterised using transmission electron microscopy and X-ray diffraction analysis. Effect of accumulated strain on the: (i) formation of systems of parallel microbands, delineated by planar boundaries, (ii) development of dislocation cells substructure and (iii) texture was evaluated.