Microstructure,tensile properties and fracture behaviour of an Al-Cu-Mg alloy 2124

The microstructure, tensile properties and fracture behaviour of aluminium alloy 2124 were studied. Detailed optical and electron microscopical observations were made to analyse the as-received microstructure of the alloy. It is shown that microstructural characteristics have a profound influence on tensile properties and quasi-static fracture behaviour of the alloy. Tensile test results indicate that the alloy has uniform strength and ductility in the longitudinal and transverse orientations. The elongation and reduction in area are higher in the transverse direction of the extruded plate. No change in fracture mode was observed with direction of testing. Fracture, on a microscopic scale, was ductile, comprising of void nucleation, growth and coalescence. The fracture process is discussed in terms of competing influences of intrinsic microstructural features, deformation characteristics of the matrix and grain-boundary failure.