The effect of a substructure of low-angle grain boundaries on the stress-strain curve of 1020 steel is shown in it. Note that the material that was cold-reduced and annealed, so as to produce a substructure, has a higher yield point and tensile strength than both the annealed material and the material which as only cold-reduced. Moreover, the ductility of the material containing a substructure is almost as good as the ductility of the annealed steel.