TITLE:
Effect of Secondary Processing and Nanoscale Reinforcement on the Mechanical Properties of Al-TiC Composites
AUTHORS:
V. Senthilkumar, A. Balaji, Hafeez Ahamed
KEYWORDS:
Nano-particulates; Aluminum; Tensile properties; Microstructure; Ductility; Orowanstrengthening;
JOURNAL NAME:
Journal of Minerals and Materials Characterization and Engineering,
Vol.10 No.14,
November
25,
2011
ABSTRACT: Aluminium based composites containing 1, 1.5 and 2wt. % of nano-sized Titanium Carbide
particulates (TiC), with an average of 45nm, reinforcement were synthesized using low energy
planetary ball mill followed by hot extrusion. Microstructural characterization of the materials
revealed uniform distribution of reinforcement, grain refinement and the presence of minimal
porosity. Properties characterization revealed that the presence of nano-TiC particulates led to
an increase in hardness, elastic modulus, 0.2% yield strength (0.2% offset on a stress-strain
curve), and the stress at which a material exhibits a specified permanent deformation, Ultimate
Tensile Strength (UTS) and ductility of pure aluminum. Fractography studies revealed that the
fracture of pure aluminum occurred in ductile mode due to the incorporation and uniform
distribution of nano-TiC particulates. An attempt is made in the present study to correlate the
effect of nano-sized TiC particulates as reinforcement and processing type with the micro
structural and tensile properties of aluminum composites. The mechanical properties, namely,
the UTS, hardness, grain size and distribution of the reinforcement in the base metal were
studied in as sintered and extruded conditions. Orowan strengthening criteria was used to
predict the yield strength of Al-TiC composites in the present work and experimental results were
compared with the theoretical results.