Effect of milling and reinforcement on mechanical properties of nanostructured magnesium composite

Recycled Mg chips were used to synthesize nanostructured Mg composite of Mg-5wt%Al reinforced with xwt% (x=1, 2 and 5) in-situ formed AIN powder. Mechanical milling was employed to produce the composite powder of crystalline size 30-43 nm. The mechanically milled (MMed) powders were subjected to uniaxial pressing, sintering and hot extrusion processes to produce bulk solid samples. After sintering at 400 degrees C and hot extrusion at 350 degrees C, the crystalline size of the composite samples still remains in nanometer range from 52 to 84 nm. The effect of milling and the percentage of reinforced AIN on the mechanical properties such as tensile strength and ductility were discussed with the general explanation of deformation mechanisms involved. (C) 2008 Published by Elsevier B.V.