Present work aims at developing Magnesium based metal matrix composite (MMC) through in-situ reaction. In-situ generation of micro and nano particles in the Mg-melt is supposed to have a better bonding with the matrix. Ceric ammonium nitrate (CAN) is added to initial Magnesium melt (with an aim to generate CeO2 and MgO through in-situ reaction) at temperatures of 670 °C and 870 °C. The developed MMCs are solution treated to get rid of intermetallic. The nature of particles is explored with X-ray diffraction (XRD) and Energy dispersion spectroscopy (EDS). The morphology and sizes of particles are keenly jotted using scanning electron microscope (SEM). Mechanical responses of developed MMCs are recorded through Hardness, Compression and scratch tests. The compression fractured surfaces are analyzed with SEM and scratched samples are analyzed on 3 D optical profilometer to explore deformation behavior. The observations indicate the in-situ formation of CeO2, MgO and CeMg12 intermetallic phases in different types and sizes. Further, these particles are responsible for improved mechanical properties. The findings are supported by the contribution of different strengthening mechanisms.

The present work aims at developing a novel superhydrophobic polymer matrix composite with enhanced wear resistance. First, polytetrafluoroethylene (PTFE) matrices were reinforced with different weight percentages (ranging from 0 to 20%) of ceria particles using the powder metallurgy method. Subsequently, the microtexture of the fabricated composites was varied by sanding them with different grit sizes of emery sheets. The effect of reinforcement was analysed on tribological behaviour of fabricated composites via a pin-on-disk test. Hydrophobic behaviour of textured PTFE and PTFE-20% ceria composite has been discussed. Surface topography and wear morphology of the polymer matrix composites were examined with an aid of SEM. Tribological data revealed that lower friction coefficient and higher wear resistance can be achieved by increasing the weight percentage of ceria particles. A maximum contact angle of 158°with a minimum roll-off angle of less than 3°was found for the PTFE-20% ceria composite.

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Mechanical and physical properties of aluminum alloys make them suitable for automotive and other structural applications. The high silicon content in aluminum improves the hardness to a great extent but at the cost of ductility. Herein, the reinforcement of near eutectic Al–Si (ADC12) alloy with the reduced graphene oxide (rGO) is demonstrated. The ADC12 alloy and its composite with rGO are cast using the gravity stir die‐casting process. The structural, mechanical, metallurgical, and tribological characteristics are conducted to understand the role of rGO as a reinforcement phase. The 0.7 wt% rGO as a reinforcement phase to ADC12 alloy reduces the friction and wear volume by 50% and ≈90%, respectively, whereas it improves the hardness by 27%. The high‐resolution transmission electron microscopy (TEM) image reveals the wrapping of microstructural silicon by rGO, which inhibits the growth of primary silicon and improves the interfacial strengthening. The high mechanical strength and low shearing properties of rGO, uniform dispersion in the ADC12 alloy, and restrained growth of primary silicon make the ADC12 alloy‐based composites potential materials for structural and low‐frictional building blocks in a diversified range of applications.

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