Effect of the Repetitive Corrugation and Straightening on the Microstructure and Mechanical Properties of a 3003 Aluminum Alloy

A novel repetitive corrugation and straightening (RCS) die geometry was evaluated in terms of its mechanical properties and microstructural modifications. An annealed 3003 aluminum alloy sheet was processed up to 6 RCS passes at room temperature, showing a significant improvement in yield strength and hardness. Changes in surface profile values were obtained along different stages of the repetitive process; this showed a clear correlation between the higher strained region and the maxima of hardness values. Moreover, differences in roughness were associated with real contact area between material and corrugating die sections. Local strain distribution generated during the process was determined by kernel average misorientation (KAM) and was consistent with microhardness mapping results. Orientation image mapping showed that grains, with the normals parallel to < 111 & rang;, activate dislocation arrangement and grain fragmentation process prior to other main directions. In spite of mechanical properties improvement, initial texture components were maintained.