Metallic materials are known to produce refined crystal grains. This grain refinement realizes superior strength and recycling capabilities. Our mass-consumption society must reconsider the importance of reusing various items. Ferrous materials were refined by cold working. Springback degrees were examined using bending tests, and mechanical properties were assessed using tensile tests because the working properties of materials were known. Results proved that the springback degrees tend to increase according to an increase of the degree of cold-working. The crystal grain size decreased. Ferrous materials strength was improved, but ductility decreased.
