Natural fibers have become increasingly popular owing to their affordability, environmental friendliness, and renewability. Owing to their abundance and low density, they have gained attention in their use as reinforcements in polymer composites. However, untreated natural fiber composites have several disadvantages, including higher water absorption, low-to-moderate mechanical properties, and challenges with fiber-to-matrix adhesion. To address these drawbacks, various approaches have been employed, such as the chemical treatment of natural fibers, fiber hybridization, and the incorporation of nanoparticles/fillers. Chemical treatment enhances the interfacial bonding with the polymer matrix by different mechanisms. Hybridization enhances the mechanical properties of composites by leveraging the advantages of individual fibers. The incorporation of nanoparticles enhances the mechanical properties and various other properties due to a significant increase in interfacial interaction, which is a result of the increased surface area of nanoparticles.

High performance lightweight structures made of metal matrix composites (MMCs) are in demand for application in variety of industries such as aircraft, spacecraft, automobile, marine, sports equipment, etc. However, uniform distribution of the reinforcement phase to improve the mechanical properties and quality of MMCs has been the challenge for the manufacturing industries. Hence, researchers are focusing on the development of traditional low-cost method of producing metal matrix composites. In the view of above facts, an attempt is made to study the processing and characterization of Si-Al alloy reinforced with zirconium dioxide particulate composites in this paper. Hence, this paper concentrates on experimentally identifying the effect of stir cast and spray forming processing techniques followed by hot pressing on micro hardness, compressive strength, and tensile strength using Taguchi’s design of experiments for aluminum silicon matrix alloy reinforced with zirconium dioxide particulates. From the extensive experimentation on aluminum and silicon reinforced with the ZrO₂ powder particulates, it was observed that there was an improvement in selected mechanical properties as the percentage of ZrO₂ increased with 13 wt.% of silicon under spray forming processing technique compared to stir cast composites. This may be due to uniform distribution homogenous dispersion, larger work hardening rate, and structure of dislocation tangles around the ZrO₂ particulates that occurred during spray forming processing technique. Further, results obtained from the interaction plot, contour plot, main effects plot, and analysis of variance (ANOVA) proved to be successful for identifying the optimum processing parameters for Si-Al alloy reinforced with zirconium dioxide particulate composites. Further, this paper also discusses wear study using pin on disc wear testing apparatus on spray forming processed aluminum and silicon (13.0 wt.%) alloy reinforced with the ZrO₂ powder particulates based on Taguchi’s design of experiments followed by second order model generation for wear using response surface methodology. Finally, electrode wear study of spray forming processed aluminum and silicon alloy reinforced with the ZrO₂ powder particulates using electric discharge machining by varying peak current (A), pulse on time (μs), and pulse off time (μs) using brass, copper, and graphite as electrode material based on L₂₇orthogonal array. The understanding gained from the design of experiments in this paper can be used to develop future guidelines for processing and characterization of Si-Al alloy reinforced with zirconium dioxide particulate composites.

Surface modified montmorillonite nanoclay created tortuous path to flow of moisture and enhanced bonding of PALF with epoxy, which resulted in lower diffusion coefficient and reduced impact of moisture diffusion in epoxy PALF nanoclay composites.

Owing to their high strength, high specific modulus, low co-efficient of thermal expansion, and excellent wear resistance, aluminium metal matrix composites reinforced with hard ceramic particles are employed in different domains. The primary heat treatment method employed to enhance the desirable properties of heat-treatable aluminium alloys and their composites is T6 treatment. This study investigated the effects of metallic reinforcement and mechanically mixed layer on the tribological characteristics of Al-Zn-Mg alloy matrix composites. The microstructure, material transfer behavior, tribological characteristics, and wear mechanism of the worn surfaces were examined. A microstructural study revealed that the reinforcements would encourage grain refining, resulting in a 60.7% average size reduction. The wear rates have significantly reduced by 50.2% and 67.2%, respectively, with the introduction of 2.0 wt% of reinforcement and T6 treatment. There is a decreasing trend of wear rate as the weight percentage of reinforcement is increased, both in as-cast and peak-aged conditions. The refractory nature of precipitates formed during T6 treatment improves the hardness of the composite and thereby reduced the wear rate. Mechanically mixed layer (MML) is observed in the worn-out surface of peak-aged composites as revealed by the SEM analysis. Overall, the Al-Zn-Mg 6 wt. % grey cast iron composite showed excellent performance in tribological characteristics.

Austempered ductile iron (ADI) is a revolutionary material that has the ability to replace some of the commonly used steel forgings. ADI is being used in wide range of products because of the availability of this material with relatively lesser cost and its higher strength to weight ratio. Manganese is an important alloying element added to ductile iron for improving the hardenability. However, the amount of manganese has to be carefully selected to avoid any adverse effect on the mechanical properties. In this study, impact energy and tensile properties are determined for the various austempering temperatures and manganese content. Statistical analysis is carried out to determine the relative contribution of each factors on the results. Higher impact energy is observed at the higher austempering temperature of 420°C. No adverse effect on impact energy is observed for the addition manganese up to 1 wt%. Response surface methodology is used to optimize the parameters for obtaining the superior combination of ultimate tensile strength and impact energy. Regression equations are fit to predict the impact energy and ductility of manganese alloyed ADI.