Gaurav Bajpai

Metal matrix composites find applications across various scientific disciplines and are in high demand worldwide. Consequently, it is imperative to enhance their mechanical properties promptly. The manufacturing of metal matrix composites poses challenges when utilizing conventional methods due to issues such as agglomeration, interfacial reactions, and wetting difficulties. Thus, the most efficient approach for producing metal matrix nano-composites (MMNCs) is through powder metallurgy in conjunction with cold iso-static compaction. This technique offers the advantage of eliminating defects like nano-particle clustering and ensuring a uniform distribution of reinforcement particles within the matrix. The primary aim of this study is to evaluate previous research regarding the capability of powder metallurgy to utilize a cold iso-static compaction chamber for achieving a consistent distribution within the metal matrix.

Al-7075 alloy with nano-SiC composite has superior mechanical properties that can be used in automobile, aerospace and defence sector to manufacture various components and body structures. In the present study, Al-7075 alloy with nano-SiC composite with different wt% of nano-SiC particles has been fabricated by the ultrasonic-assisted stir casting method. Uniform mixing of the nanosized SiC particles in the Al-7075 alloy has been achieved from ultrasonification and as-cast and T6 heat-treated samples were prepared. The diverse mechanical properties such as tensile strength, impact strength and hardness have been examined for the as-cast samples with different wt% of nano-SiC and T6 heat-treated samples.

In the present scenario, weight diminution and strength enrichment are the main requirements for escalating the application of a nano composite material in different sectors. Several industrial sectors, such as automobile, defense and aerospace, are making various components of nano composites with the help of powder metallurgy processing. In this study, Al nanoTiC_p composites (2, 4 and 6 wt %) were contrived through modified powder metallurgy (PM) techniques with the help of Cold Isostatic Compaction process (CIP). The mechanical properties such as density, porosity, micro-hardness, compressive strength and indirect tensile strength were increasing with the reinforcement of nanoTiC_p particles up to 4 wt % in Al metal matrix composites. Nevertheless, clustering of nanoTiC_p particles were found at 6 wt %, which is also observed in SEM images.

A detailed structural and electronicstudy of sol-gel synthesized and 1100°C calcined Zn_1-xSi_xO (0 ≤ x ≤ 0.06) nano-particles were carried out using XRD, FESEM, UV- vis/PL spectroscopy studies. XRD reveals wurzite structure at (0 ≤ x ≤ 0.03) after which some extra phase is seen which is also supported by FESEM images.UVs spectroscopy revealed that band gap increases and urbach energy decreases with substitution. Due to doping of Si⁴⁺, oxygen deficiency is decreased which improve structural properties in spite of introduction of strains due to lattice contraction.Photoluminescence studiesrevealed that the reduction in defects state in the sample with Si⁴⁺ substitution.