The studies of microstructure, properties and fracture mechanism have been conducted on AI
2014 matrix alloy reinforced with 10 volume percent (Composite 1) and 15 volume percent
(Composite 2) of alumina (A/20 3) particles respectively Microstructure observation of the composite
specimens was focused on the distribution of alumina reinforcement particles in different orientations.
It was found that Composite 1 showed a more evenly distributed particles compared to that of
Composite 2. The measurement of sonic modulus was carried out by using GrindoSonic MK5
Industria/Instrument. All the sonic modulus properties (flexural, longitudinal and torsional moduli)
of Composite 2 were found to be higher than Composite 1. The testing of impact strength was
done by means of Charpy impact test (V-notched specimen). It has found that the impact strength
of Composite 1 (5.42 J) was higher as compared to Composite 2 (4.07 J). The fracture surfaces
after impact test for the composite samples were investigated by using scanning electron microscopy
in order to characterise the fracture mechanism of the composites. The fracture mechanism of
Composite 1 was indicated by matrix ductile rupture and decohesion of particle-matrix interface,
whereas matrix brittle rupture by particle fracture was found in Composite 2.
