Production of functionally graded materials from electrochemically modified carbon preforms

A new process based on carbon as a precursor material has been applied successfully to the production of graded Al2O3/Al composites. For this purpose, distinct porosity gradients were introduced into carbon materials via anodic oxidation, The graded structure of the carbon preforms was replicated using two subsequent infiltration steps to yield fully dense Al2O3/Al functionally graded materials with an interpenetrating network microstructure and a continuous variation of metal content.