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In the present work stir casting route is used to fabricate the ZA27 Metal matrix composites containing 3 wt%, 6 wt%, 9 wt%, and 12 wt%. Zircon sand particulates of size 100 mesh. Microstructure studies using Optical Microscopy, SEM-EDAX are carried out to ascertain the distribution and morphology of particulates in the composites. Effect of zircon sand as reinforcement on bulk density, porosity, of the fabricated composites is studied. SEM studies are carried out to understand the behavior of as-cast ZA27 alloy reinforced with zircon sand. The dislocation density of the fabricated composite affects the strength of the composites and depends on the strain due to thermal mismatch and is found to increase with increase in weight% of zircon sand. However, it does not consider casting defects of voids/clustering observed in micrographs of the fabricated composite. Porosity in composites does not have influence on Coefficient of thermal expansion (CTE) of the ZA27 composites studied using thermoelastic models like Kerner and turner model and rule of mixtures of composite.

Zinc-Aluminum alloys are employed as a bearing material in various machinery. In the present work zircon sand microparticles of size, 100 µm are dispersed in ZA-27 alloy with weight fractions of 1.5 wt%, 3.0 wt%, 4.5 wt%, and 6.0 wt% to synthesize ZA-27 metal matrix composites by stir casting. Microstructure studies using, SEM/EDAX conducted to determine the morphology of the particles and the ZA-27composites. Physical properties like density and porosity of the zircon sand microparticulate reinforced ZA-27 are evaluated and their effect on strength and ductility of the composites are evaluated using the tensile test. dispersion of zircon sand is seen in the SEM micrographs and EDAX confirms the same. The results obtained revealed an increase in tensile strength and yield strength at 3.0 wt%, 4.5 wt and 6.0 wt% at the cost of a reduction in percentage elongation when compared to ZA-27 alloy. The tensile behavior of ZA-27 composites is found to be affected by the dispersion of reinforcement in the matrix arising due to dislocation density.

During the last few years, ZA-27 alloys are commercially used as a bearing material due to their excellent tribological properties. This alloy also possesses advantages like good mechanical properties, low energy consumption, and ease of machining. It is found that ZA-27 alloys lose their dimensional stability above 100 °C during its usage. This has inspired many researchers in recent years to explore the possibility of reinforcing ZA-27 alloy with synthetic ceramic reinforcement like SiC, Alumina, boron carbide Agricultural and industrial wastes along with solid lubricant such as graphite for tribological applications. This article reviews the microstructure, physical, mechanical, wear, and corrosion properties of ZA-27 hybrid MMC reinforced with microparticles like SiC, and Alumina, Rice husk ash, Groundnut ash, Quarry dust, and Bamboo leaf ash fabricated by stir casting technique. This paper summarizes the work done by several researchers in optimizing the stirring parameters for better distribution of microparticulate reinforcements and mechanical, corrosion and wear behavior of the hybrid ZA-27 composites.