Improving Mechanical and Corrosion Properties of 6061 Al Alloys via Differential Speed Rolling and Plasma Electrolytic Oxidation

This study explores the combined potential of severe plastic deformation (SPD) via differential speed rolling (DSR) and plasma electrolytic oxidation (PEO) to enhance the material performance of 6061 Al alloys. To this end, DSR was carried out at a roll-speed-ratio of 1:4 to obtain similar to 75% total thickness reduction and a final microstructure of < 1 mu m. The rest of the samples were annealed to obtain various grain sizes of similar to 1, similar to 25, and similar to 55 mu m. Through DSR, the hardness of the material increased from similar to 64 to similar to 102 HV. Different grain sizes altered the plasma behavior which further influence the growth of the coating layer, where the fine grain size produced a compact structure beneficial for corrosion protection. This synergy offers tailored materials ideal for high-performance applications across diverse industries, combining enhanced bulk properties from DSR with optimized surface attributes from PEO.