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In this article, an attempt was made to study the mechanical behaviour of AA7068 - 6 vol. % of MoS2 - X vol. % of WC (X = 0, 5, 10 and 15) hybrid aluminium composites produced by blend–press–sinter methodology. Compacted Powders (700MPa) were sintered at different temperatures (450 0c, 500 0c and 550 0c ) in order to find the influence of sintering temperature on mechanical properties and tribological behavior of AA7068 hybrid composites.The sintered samples have been characterized by x-ray diffraction (XRD) method for identification of phases and also to investigate the phase changes. The change in density, hardness and porosity values of composites were reported. The composite with 15 vol. % of tungsten carbide and 6 vol. % of MoS2 showed the highest hardness and density at the sintering temperature range of 550 0c. Pin-on-disc type apparatus was used for determining the wear loss occurring at different conditions. The hybridization of the two reinforcements enhanced the wear resistance of the composites, especially under high applied load, sliding distance and sliding speeds. Due to this, the hybrid aluminium composites can be considered as an outstanding material where high strength and wear-resistant components are of major importance, predominantly in the aerospace and automotive engineering sectors. The morphology of the wear debris and the worn out surfaces were analyzed to understand the wear mechanisms.

Composites are widely utilized in the industries like automobile, aircraft, space craft, transport, generation of wind-power and so on due to its lightweight and inexpensive. Recently, dissimilar physical and chemical features of materials are intercorporate to produce an innovative composite material. Many researches had performed research on those composite materials. In this research, fly ash materials are utilized in the form of reinforcement due to their improved mechanical characteristics like enhanced UTS, impact and compressive strength, toughness and low intensity and ductility. Fly ash is also known as fuel ash. In this research fuel ash is reinforced with aluminium metal matrix composites. MMC are prepared by using the fabrication techniques of solid and liquid stage.

The wear behavior of Al/SiC composites prepared by stir casting technique is investigated to find out the effects of the weight percentage of SiC, load, and the number of strokes on a shaper machine. Metal matrix composite (MMC) pins are prepared with different weight percentages of SiC (10%, 15%, and 20%). The tests are carried out with different load conditions (25, 50 and 75 N) and different number of strokes (420,780 and 1605 strokes). Wear surfaces of tested samples are examined in scanning electron microscope (SEM). Hardness and impact tests are also carried out on the MMC samples. The experimental results show that the hardness of composites increases with an increase in SiC particle, and the impact strength decreases with increase in SiC content. The volume loss of MMC specimens are less than that of the matrix alloy. Moreover, the temperature rise near the contact surface of the MMC specimens increases with increase in wt% of SiC, load, and number of strokes. The coefficient of friction decreases with increase in load and the number of strokes.

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