Journal of Advancements in Material Engineering

Analysis of Microstructure using Digital Optical Microscope

P. V. Lahamge — 2026-06-10

The internal microstructure of engineering materials directly governs their macroscopic mechanical and physical performance, including critical parameters such as tensile strength, yield hardness, structural ductility, and wear resilience. Traditional methods of metallographic evaluation rely heavily on conventional manual optical microscopes, which are often prone to human subjectivity, lack robust real-time digital documentation systems, and present distinct operational bottlenecks in high-throughput industrial and research environments. This comprehensive study investigates the implementation and evaluation of an advanced Digital Optical Microscope (DOM) system as a versatile, cost-effective, and highly reliable tool for cross-disciplinary microstructural characterization. Utilizing a wide magnification spectrum spanning 50x to 1000x paired with a flexible focal envelope of 0-40mm, various metallic specimens and industrial substrates were analyzed following standard metallurgical preparation pipelines—encompassing sectioning, mounting, precision grinding, mirror polishing, and selective chemical etching. The integration of high-resolution digital imaging sensors with dedicated edge-detection and image segmentation software successfully facilitated automated quantitative measurements of ASTM grain boundary distributions, secondary phase area fractions, surface topography flaws, macro-scale inclusions, and localized micro-porosity. Beyond core metallurgical evaluation, the operational versatility of the DOM was validated across diverse high-precision engineering applications, including electronic printed circuit board (PCB) trace inspection, textile weave densitometry, high-fidelity jewelry authenticity verification, and currency security feature analysis. The empirical results confirm that digital light-optical systems provide a superior ergonomic, repeatable, and highly efficient workflow for routine material diagnostics, serving as an optimal and accessible bridge between traditional manual light microscopes and expensive, operationally intensive scanning electron microscopy (SEM) instruments.

Graphene-based Fabrics for Defence Applications: Opportunities, Challenges, and Future Directions

M. Abdullah Khan — 2026-02-24

Graphene’s exceptional electrical, mechanical, thermal and optoelectronic properties make it a leading candidate for enabling next-generation smart textiles and wearable communication platforms tailored to defence and tactical applications. This study presents a comprehensive review of graphene-enabled smart fabrics with particular emphasis on fabrication methods, printed/laminated wearable antennas, integrated energy harvesting and storage, and electromagnetic interference (EMI) mitigation relevant to battlefield use. Recent advances in scalable graphene inks and screen-printing methods, as well as hybrid grapheme metal composites that improve conductivity, are summarized and compared. Progress in graphene-based wearable antennas and textile integration demonstrates promising performance in body-centric communications, while graphene-based EMI shielding and functionalized graphene fiber offer routes for enhanced survivability against electronic warfare and harsh environmental conditions. Key technical challenges, such as conductivity at high frequencies, durability under repeated washing and abrasion, large-scale manufacturability, and standards for defence-grade testing, are critically examined. Finally, identify research gaps and propose a roadmap for transitioning graphene smart fabrics from laboratory prototypes to field-deployable defence systems, including integration with 5G/6G, LiFi, and AI-driven internet of battlefield things (IoBT) architectures.

Comprehensive Design and Performance Analysis of Lithium-ion Battery Systems for Mobile Device Applications

Emekwisia, Chukwudubem C — 2026-06-12

Electrochemical energy storage systems, particularly lithium-ion batteries, play a central role in powering modern portable electronics. This study investigates the design and performance evaluation of lithium-ion batteries tailored for mobile device applications, with an emphasis on material optimization to enhance power density and extend cycle life. Utilizing a spinel-structured Lithium Manganese Oxide (LMO) cathode and an intercalated graphite anode, a prototype cell was fabricated using manual slurry preparation, casting, and vacuum electrolyte filling. Key performance metrics, including Open Circuit Voltage (OCV) and rate-dependent power densities, were systematically assessed. The OCV test recorded a stable maximum voltage of 3.81 V, demonstrating excellent voltage retention and reliable phase stability during C/9 charge-discharge relaxation cycles. Furthermore, under baseline conditions, the cell achieved a gravimetric power density of 240.15 W/kg and a volumetric power density of 307.51 W/L. Accelerated rate testing revealed exceptional power scaling, reaching a peak gravimetric output of 1200.75 W/kg at a 5C discharge rate. Overall, this research advances the development of efficient, safe, and cost-effective lithium-ion batteries optimized to meet the growing fast-charging and high-capacity performance demands of the modern mobile technology industry.

Performance Assessment of Biomass Gasification for Decentralized Power Generation Applications

Sachin Sangale — 2026-05-13

The transition toward sustainable and decentralized energy systems has intensified research interest in biomass-based power generation technologies. Biomass gasification offers an efficient thermochemical pathway for converting agricultural residues into synthesis gas (syngas), which can be utilized for decentralized electricity generation. This study presents a comprehensive performance assessment of a downdraft biomass gasification system for small-scale decentralized power applications. Locally available agricultural residues were characterized using proximate, ultimate, and calorific value analyses. Gasification performance was evaluated using key indicators, including cold gas efficiency, carbon conversion efficiency, specific gas yield, and syngas calorific value. The influence of operating parameters such as equivalence ratio and gasification temperature on syngas quality was analyzed. Results indicate that air gasification produces syngas with a lower heating value of 4.5–6.0 MJ/Nm³ and a cold gas efficiency of 60–70% under optimal conditions. The findings confirm that biomass gasification is a technically feasible, environmentally sustainable, and economically viable solution for decentralized power generation, particularly in rural and off-grid regions.

Comparative Sol–Gel Synthesis Approaches for BiFeO₃ Nanoparticles for Photovoltaic Solar Cell Applications

Md. Meganur Rhaman — 2026-01-02

Multiferroic Bismuth Ferrite (BFO), characterized by a direct optical bandgap in the range of 2.2 to 2.7 eV, has emerged as a favorable material for next-generation Photovoltaic (PV) and optoelectronic applications. However, obtaining phase-pure BFO nanoparticles remains a substantial challenge because of the volatility of bismuth and the narrow thermodynamic stability window of the perovskite phase. In the present study, high-purity multiferroic BiFeO₃ nanoparticles were successfully synthesized via an energy-efficient, low-temperature sol–gel route employing two distinct approaches: General Sol-gel and Tuned Sol-gel synthesis. The precursor sol was carefully adjusted to a pH of 1–2 using NH₄OH, while ethylene glycol was applied as a chelating and polymerizing agent to ensure homogeneous complexation of Fe³⁺ and Bi³⁺ ions. Following gel formation, the dried intermediates were annealed at 600°C to achieve phase crystallization. A comprehensive investigation was conducted to evaluate how these synthesis pathways influence crystal purity, structural characteristics, and multiferroic behavior. UV–VIS–NIR spectroscopic analysis confirmed the presence of a direct optical bandgap, consistent with intrinsic BFO. X-ray Diffraction (XRD) results verified that all the samples were structured in a single-phase rhombohedral perovskite (space group R3c), while refinement of diffraction patterns provided detailed insight into crystallite size, microstrain, and structural order. The morphology, elemental distribution, and particle-size evolution were further observed using field-emission scanning electron microscopy furnished with energy-dispersive spectroscopy, confirming uniform particle formation and compositional accuracy. Comparative analysis of the two sol–gel techniques revealed that the Tuned Sol-gel method yielded BFO nanoparticles of superior phase purity and structural integrity, with fewer secondary phases than those produced by the General Sol-gel method. Overall, this study demonstrates that Tuned Sol-gel processing offers a more reliable pathway for fabricating high-quality BFO nanoparticles suitable for photovoltaic and multifunctional device applications.