Mechanical behaviour of SiC reinforced aluminium thin walled tube under combined axial and torsional loading

Metal matrix composite materials are designed and engineered to exhibit properties that are most desirable for a given application. The properties of the composite will depend upon the particular constituents and volume fraction used, but most MMCs show improvement in stiffness, wear and fracture resistance over the matrix material. The yield and ultimate tensile strength, and the elastic modulus of the material, increased with heat treatment and volume fraction of silicon carbide particles at the expense of ductility. This paper examines the mechanical behaviour of an AlSiC metal matrix composite with 17.8% volume fraction of 3 mum SiC particles in a 2124 aluminium matrix. Extruded and heat-treated (T4) thin tubular specimens were used in the experiments. The specimens were subjected to non-proportional tension and torsion loadings. In the first set of experiments, specimens were subjected to an initial angle of twist in the elastic range followed by axial load, maintaining initial angle of twist. In the second set of experiments, specimens were subjected to an initial axial displacement in the elastic range followed by torsion load, maintaining initial axial displacement. (C) 2004 Elsevier B.V. All rights reserved.