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The nanostructured titanium was fabricated via the surface mechanical attrition treatment (SMAT) process and the effect of nano-crystalline structure on the biomechanical and biocorrosion properties were studied. It was found that the Young’s modulus of nanostructured Ti decreased significantly and thus the biomechanical property was improved. The electrochemical results revealed that the corrosion resistance of Ti became worse after SMAT process, which is contributed to the higher activation of the nanostructured surface.

2024Al hybrid composites reinforced with 20vol% SiC whiskers and 0vol%, 2vol%, 5vol% and 7vol% SiC nanoparticles respectively, were fabricated by squeeze casting technique. The results show that the reinforcements distribute homogeneously in the matrix of the as-cast composites. Hot extrusion leads to a directional distribution of the SiC whiskers and a more homogenous spatial distribution of the SiC nanoparticles in the composites. Tensile test indicates that the tensile strength and modulus of the composites increase with increasing content of the nanoparticles and raises further after extrusion.

Metal matrix composites with the matrix of pure Mg and the hybrid reinforcements of SiC particulates and Al 2 O 3 .SiO 2 (mullite) short fibers were fabricated by the liquid pressure infiltration process. It was found that the tensile strength and elastic modulus of Mg matrix composites with reinforcements of 8 vol% and 18 vol% was improved distinctly, compared with that of pure Mg. While damping capacity of the composites was decreased with increase of reinforcements due to the reduction of damping dependence on strain amplitude. And based on the TEM observation of dislocation configuration, it was concluded that the movement of dislocations in the composites was hindered by the reinforcements and thus reduced the damping capacity according to the G-L model.