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The current research work primarily focuses on synthesizing and exploring Al2014 alloy microstructure and wear behavior reinforced with 20 μm Al2O3 (alumina) particles. A novel two-stage stir casting (melt stirring) technique is adopted to produce the composites, and the weight percentage of reinforcement is maintained at 9, 12, and 15 to know the effect of varying weight percentage on microstructure and wear behavior. To achieve better dispersion, alumina particles have been introduced in two stages. X-ray diffraction (XRD) and electron microscope/energy-dispersive spectroscope (EDX) are used to characterize the prepared composites. In the Al2014 matrix, microstructural characterization showed a fairly uniform dispersion of Al2O3p. The presence of alumina is confirmed by the XRD pattern carried out on the produced composite (Al2014-15 wt.% Al2O3p). Wear properties of as-cast Al2014 alloy and composites (Al2014-Al2O3p) at 9, 12, and 15 wt.% have been studied. Dry sliding wear tests have been conducted over a load range of 9.81 N-49.05 N and sliding speed of 100–600 RPM using pin-on-disk machine. Results revealed the frictional coefficient of as-cast Al2014 alloy and produced composites increase with an increase in load up to 49.05 N. Nevertheless, the frictional coefficient of both as-cast Al2014 alloy and produced composite increase continuously by increasing the speed. The wear rate of both Al2014 matrix alloy and Al2014-Al2O3 reinforced composite increase with the increase in load and sliding speed. To know the possible wear mechanisms, worn surface and wear debris have been studied by using electron microscopy and EDS examination to specify the formation of the oxides.

In the current research work synthesis, characterization, mechanical and wear behavior of 2, 4 and 6 wt% of nano-ZrO2 particulate-reinforced AA2014 alloy composites have been investigated. The matrix phase of AA2014 alloy containing nano-ZrO2 particulates composites was geared up by two-stage melt stir system. After the preparation, the organized composites were studied by SEM and EDS for analyzing the microstructures and chemical elements. Further, mechanical characterization and wear studies of as-cast AA2014 alloy and AA2014-nano-ZrO2 composites were studied. From the investigation, it was observed that the tensile behavior of composites was enhanced due to addition of nano-sized ZrO2 particles in the AA2014 alloy matrix. In nano-ZrO2-reinforced composites, the percentage elongation decreased. Further, the wear loss increased with respect to the load for all the prepared materials. To study the fractography and different wear mechanisms for various test conditions of different compositions, tensile fractured surfaces and the worn surfaces were observed by SEM.

The present work deals with the preparation of the aluminium matrix composite using a ceramic and metallic combination as reinforcements and using liquid metallurgy route of solidification process. The desired properties of composites have been influenced by the solidification behaviour of the cast metal matrix composites, which has been imposed to study the solidification behaviour of metal matrix at different weight fraction of reinforcement particulates. Al7075 was used as matrix and tungsten carbide, and cobalt particulates were used as reinforcements. During the preparation, an addition of magnesium was used to increase the wettability of the particulates during the mixing. XRD/EDX/SEM characterizations of the prepared composites were conducted, where a fairly uniform distribution of the reinforced particulates was found over the matrix.

In the present work, ternary Al–Ti–B master alloys have been prepared in an induction furnace by the reaction between preheated halide salts (K2TiF6 and KBF4) and liquid molten Al. A number of process parameters such as reaction temperature (800, 900, 1,000 °C), reaction time (45, 60, 75 min.) and compositions (Ti/B ratio: 5/1, 1/3) have been studied. The indigenously prepared master alloys were characterised by chemical analysis, particles size analysis, XRD and SEM/EDX microanalysis. Results of particle size analysis suggest that the sizes of the intermetallic particles [Al3Ti and TiB2 in Al–5Ti–1B and (Al, Ti)B2 in Al–1Ti–3B] present in various Al–Ti–B master alloys increases with increase in reaction temperature (800–1,000 °C) and reaction time (45–75 min.). The population of the particles decreases with increase in reaction time and temperature. Further, SEM/EDX studies revealed that different morphologies of the intermetallic particles were observed at different reaction temperatures and reaction times. Further, the performances of the above-prepared master alloys were assessed for their grain refining efficiency on Al–7Si alloy by macroscopy, DAS analysis. Grain refinement studies suggest that, B-rich Al–1Ti–3B master alloy shows better grain refinement performance on Al–7Si alloy when compared to Ti-rich Al–5Ti–1B master alloy.