Journal Articles
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Item Review on fiber composites for sustainable high strain rate applications(Elsevier Inc., 2025) Lakshme Gowda, D.M.; Bhat, R.S.; Rangappa, S.M.; Siengchin, S.Over the past two decades, the growing demand for sustainable, high-performance materials has driven significant advancements in fiber reinforced polymer composites (FRPCs), particularly for dynamic and ballistic applications. This review provides an integrated overview of recent developments, highlighting sustainable reinforcements, novel stacking configurations, and advanced machine learning (ML) predictive approaches. Particular emphasis is placed on bio-inspired helicoidal laminates and hybrid architectures, which offer superior energy absorption, damage tolerance, and impact mitigation. Hybrid laminates incorporating satin weaves, high-modulus fibers, and compliant matrices enhance post-impact toughness and better structural integrity. Additionally, embedding a high-hardness (70–90 Shore A) rubber core with a compliant matrix mitigates conical crack propagation, improves strain rate sensitivity, and reduces delamination under both low- and high-velocity impacts. The dynamic response of FRPCs is examined using experimental techniques such as Split Hopkinson Pressure Bar (SHPB) testing and impact assessments, revealing the influence of design variables on strain-rate-dependent behavior. To support material selection and design optimization in fiber composites, ML techniques, Ashby charts, and Multi-Criteria Decision-Making (MCDM) frameworks are explored, balancing performance, sustainability, and manufacturability. Failure mechanisms such as delamination, fiber pull-out, and matrix cracking are analyzed with respect to hybridization strategies and environmental effects. Finite element analysis (FEA) tools, including ABAQUS, ANSYS AUTODYN, and LS-DYNA, are reviewed for their predictive accuracy, validated against experimental results. Standardized testing protocols (ASTM D7136, D7137, F1342; NIJ-0101.06) ensure the consistent evaluation of both flexible and rigid armor systems. The review also discusses manufacturing advancements such as resin transfer molding (RTM) and filament winding, which improve scalability and reduce waste. Non-destructive testing (NDT) methods, including acoustic emission, ultrasonic C-scanning, and X-ray CT, are highlighted for real-time damage assessment. Finally, integrating ML algorithms such as MLP, SVM, RF, and CNN with experimental and simulation data enhances predictive modeling, damage classification, and tailored composite design. This convergence of bio-inspired design, computational tools, and intelligent systems is accelerating the development of next-generation FRPCs for aerospace, defense, automotive, and civil engineering applications. © 2025 The AuthorsItem Heat transfer during the solidification of an Al-Cu-Si alloy (LM4) and commercial pure tin in single steel, graphite, and graphite-lined metallic (composite) molds was investigated. Experiments were carried out at three different superheats. In the case of composite molds, the effect of the thickness of the graphite lining and the outer wall on heat transfer was studied. Temperatures at known locations inside the mold and casting were used to solve the Fourier heat conduction equation inversely to yield the casting/mold interfacial heat flux transients. Increased melt superheats and higher thermal conductivity of the mold material led to an increase in the peak heat flux at the metal/mold interface. Factorial experiments indicated that the mold material had a significant effect on the peak heat flux at the 5% level of significance. The ratio of graphite lining to outer steel wall and superheat had a significant effect on the peak heat flux in significance range varying between 5 and 25%. A heat flux model was proposed to estimate the maximum heat flux transients at different superheat levels of 25 to 75°C for any metal/mold combinations having a thermal diffusivity ratio (?R) varying between 0.25 and 6.96. The heat flow models could be used to estimate interfacial heat flux transients from the thermophysical properties of the mold and cast materials and the melt superheat. Metallographic analysis indicated finer microstructures for castings poured at increased melt superheats and cast in high-thermal diffusivity molds.(Effect of superheat, mold, and casting materials on the metal/mold interfacial heat transfer during solidification in graphite-lined permanent molds) Prabhu, K.; Suresha, K.M.2004Item Epoxy systems with and without different volume fractions of fly ash particulate fillers are made and their absorption due to immersion in saline water maintained at room temperature are established through weight measurements recorded up to 100h. The 100-h exposed samples are additionally subjected to compression tests to evaluate the strength. The results show that both neat epoxy and fly ash-bearing composites exhibit differing levels of aqueous medium absorption - it being less in ash-free samples. When the ash content in the system is large, the absorption levels are high. The data further revealed that the unexposed samples generally record an increasing strength value with ash content. However, for the exposed cases, a reversal in trend with the ash content is noticed. Attempts to explain these differing trends are made in this work by analyzing the features observed on the surface of compression-failed samples using fractography employing scanning electron microscopy (SEM). © 2005 Sage Publications.(Compression strength of saline water-exposed epoxy system containing fly ash particles) Kishore; Barpanda, P.; Kulkarni, S.M.2005Item The inhibition efficiency of Glycyl Glycine (GG) on the corrosion behaviour of Al-SiC(p) composite in 0.01, 0.1 and 1.0 N HCl solution has been investigated in the temperature range 30°-50°C using polarization techniques. The results indicate that GG acts as an anodic inhibitor and is chemisorbed following Temkin's model. The inhibitor efficiency increases with increase in inhibitor concentration and also with increase in temperature for a given inhibitor concentration. © 2006 SAEST.(Glycyl glycine as corrosion inhibitor for aluminium silicon carbide composite in hydrochloric acid) Rao, S.A.; Padmalatha; Nayak, J.; Nityananda Shetty, A.N.2006Item Higher order refined computational models for the free vibration analysis of antisymmetric angle ply plates(2008) Swaminathan, K.; Patil, S.S.Analytical formulations using two higher order refined displacement models have been developed and solutions presented for the first time to the natural frequency analysis of antisymmetric angle-ply composite and sandwich plates. These computational models already reported in the literature are based on Taylor's series expansion of the displacements in the thickness coordinate and consider the realistic parabolic distribution of transverse shear strains through the laminate thickness. One of them, with 12 degrees of freedom, considers the effects of both transverse shear and normal strain/stress while the other with 9 degrees of freedom includes only the effect of transverse shear deformation. In addition to above, a few higher order models and the first order model developed by other investigators and available in the literature are also considered for the evaluation. A simply supported plate is considered throughout as a test problem. The equations of motion are obtained using Hamilton's principle. Solutions are obtained in closed form using Navier's technique by solving the eigenvalue equation. Plates with varying slenderness ratios, number of layers, fiber orientations, degrees of anisotropy, edge ratios and thickness of core to thickness of face sheet ratios are considered for the analysis. Accuracy of the theoretical formulations and the solution method is first ascertained by comparing the results with those already available in the literature. After establishing the accuracy of the solutions, extensive numerical results are presented for the free vibration analysis of multilayer antisymmetric angle-ply composite and sandwich plates using all the models, which will serve as a benchmark for future investigations. © SAGE Publications 2008.Item The inhibition action of ethyl-2-phenyl hydrozono-3-oxobutyrate on the corrosion of 6061 Al alloy/SiCp composite in hydrochloric acid medium(Sociedad Chilena de Quimica, 2010) Kini U, U.A.; Shetty, P.; Shetty, S.D.; Isloor, A.M.; Herle, R.The inhibition behavior of ethyl-2-phenyl hydrozono-3-oxobutyrate on the corrosion of 6061 Al alloy/SiCp composite in 0.1, 0.5 and 1 N hydrochloric acid solution at four different temperatures (30-60 °C) has been investigated using potentiostatic polarization techniques and weight loss method. The results indicated that the corrosion inhibition efficiency and the extent of surface coverage were increased with the increase in inhibitor concentration up to a critical concentration. The adsorption of the inhibitor compound on the composite surface was found to obey Temkins' and Langmuir adsorption isotherms. The potentiostatic polarization results have revealed that oxobutyrate acts as an efficient cathodic inhibitor for the corrosion of 6061 Al alloy/SiCp composite in HCl medium. The thermodynamic parameters for the corrosion and adsorption processes were determined. © 2010.Item Potential use of natural fiber composite materials in India(2010) Saravana Bavan, D.; Mohan Kumar, G.C.M.This study focuses on the potential use of natural fibers in composite materials, their availability, processing features, mechanical and physical properties, and some of their applications in India. © 2010 The Author(s).Item Improved utilization of desiccant material in packed bed dehumidifier using composite particles(2011) Ramzy K, A.; Kadoli, R.; Ashok Babu, T.P.Solid desiccant dehumidifiers are widely used in drying processes. In most of these dehumidifiers, the desiccant material is used as packed bed of granule or spherical particles. Investigations of intra-particle heat and mass transfer processes has shown that the entire portion of the particle is not participating effectively during adsorption as well as desorption processes [Pesaran AA, Mills F. Moisture transport in silica gel packed beds-I. Theoretical study. International Journal of Heat and Mass Transfer 1987; 30: 1037-49]. This is because the diffusion rate is very small compared to that of convection. In the present work, a new desiccant composite particle, in which the unutilized portion of the spherical desiccant particle is replaced with an inert particle, is proposed. By replacing the conventional particles with composite particles for the same mass of desiccant material, the available area for heat and mass transfer increases and more amount of desiccant material is effectively utilized. Further, in order to ascertain the improvement in the performance of the desiccant bed using the composite particles, various factors like thermo-physical properties of the inert material, composite particle thickness ratio, bed configuration, bed volume, the pressure drop and the increase in total adsorbed or desorbed mass have to be considered. In view of this, a theoretical investigation of the operation of vertical solid desiccant packed bed dehumidifier, using both conventional silica gel particles as well as the new proposed composite silica gel particles has been reported. A modified solid side resistance (MSSR) model is developed for the prediction of intra-particle temperature and water content profiles. Results of the present theoretical models, when applied to packed bed of conventional silica gel particles, agree well with the experimental results from the literature for both desorption and adsorption processes. From the theoretical results, more utilization for the desiccant material is obtained when ordinary silica gel particles are replaced by composite silica gel particles. For the same amount of desiccant material and same mass flow rate of air, using particles of 0.2 thickness ratio the pressure drop decreases by about 60% for the case investigated. In addition, an increase of about 11.07% and 20.46% in total mass adsorbed and desorbed respectively are obtained. At the time when adsorption process ends, an increase of 15.5% in the bed effectiveness has been obtained. In addition, the expected improvement in total mass adsorbed and desorbed is observed to be dependent on the inert material thermo-physical properties for thickness ratio less than 0.5. An optimization technique relating the composite particle design, resulting savings in pressure drop and bed volume increase is proposed. © 2010 Elsevier Ltd.Item Corrosion inhibition of 6061 aluminium alloy/SiCp composite in hydrochloric acid medium using 3-chloro-1-benzothiophene-2-carbohydrazide(2011) Kini U, U.; Shetty, P.; Divakara Shetty, S.; Arun Isloor, M.The inhibitive action of 3-chloro-1-benzothiophene-2-carbohydrazide (CBTC) on the corrosion behavior of 6061 Al alloy/SiCp composite has been studied at four different temperatures (30°, 40°, 50° and 60°C) in hydrochloric acid medium (0.5 and 1 M) using Tafel extrapolation technique and weight loss method. Polarization curves indicate that CBTC acts as cathodic inhibitor. Inhibition efficiency is found to increase with increasing inhibitor concentration upto a critical value and with decreasing temperature. The inhibition efficiencies obtained by Tafel extrapolation technique and weight loss method are in good agreement. The adsorption of the inhibitor on the composite surface is found to obey Temkins' and Langmuir adsorption isotherms. The inhibition is governed by physisorption mechanism.Item Morphological and thermal properties of maize fiber composites(Korean Fiber Society, 2012) Saravana Bavan, D.; Mohan Kumar, G.C.Maize stalk has become one of the major sources of fibers from the agricultural residues. Use of these fibers as a reinforcement in the polymer is described in this paper. The present work is focused on establishing the properties such as physical, chemical, morphological structure and thermal properties of maize stalk fiber using different characterization techniques. Simple hand layup method was followed for processing the composite material. Chemical treatments of fibers were carried out to study the interaction of fibers with the matrix. The results revealed that maize fibers can also be used as a traditional fiber as reinforcement in a natural fiber reinforced composite materials. © 2012 The Korean Fiber Society and Springer Science+Business Media Dordrecht.