Journal Articles
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Item A comprehensive review on material selection for polymer matrix composites subjected to impact load(China Ordnance Industry Corporation, 2021) Mahesh, V.; Joladarashi, S.; Kulkarni, S.M.Polymer matrix composites (PMC) are extensively been used in many engineering applications. Various natural fibers have emerged as potential replacements to synthetic fibers as reinforcing materials composites owing to their fairly better mechanical properties, low cost, environment friendliness and biodegradability. Selection of appropriate constituents of composites for a particular application is a tedious task for a designer/engineer. Impact loading has emerged as the serious threat for the composites used in structural or secondary structural application and demands the usage of appropriate fiber and matrix combination to enhance the energy absorption and mitigate the failure. The objective of the present review is to explore the composite with various fiber and matrix combination used for impact applications, identify the gap in the literature and suggest the potential naturally available fiber and matrix combination of composites for future work in the field of impact loading. The novelty of the present study lies in exploring the combination of naturally available fiber and matrix combination which can help in better energy absorption and mitigate the failure when subjected to impact loading. In addition, the application of multi attributes decision making (MADM) tools is demonstrated for selection of fiber and matrix materials which can serve as a benchmark study for the researchers in future. © 2020 The AuthorsItem Effect of Mechanical Alloying on the Microstructure of CoCrNiTiMo x High Entropy Alloy(Springer, 2022) Addepalli, S.N.; Joladarashi, S.; Ramesh, M.R.; Arya, S.B.The present research focuses on synthesizing nanocrystalline CoCrNiTiMox (x: molar ratio; x = 1, 1.5 at.%, respectively) high entropy alloy by mechanical alloying of pure metal powders for further application as feedstock in the atmospheric plasma spray process. The paper describes the phase evolution and microstructural transformation of milled powders with respect to the ball milling time and speed. A Retsch PM 100 ball mill with a ball to powder ratio of 10:1 and speeds of 200 and 300 rpm are used to synthesize the feedstock powder for plasma spraying. The ball milled powders were assessed for particle size, phase transformation and surface morphologies at regular intervals of 10, 20, 30, 40 and 50 h to optimize the ball mill process parameters. The particle morphology and chemical homogeneity studies were done by scanning electron microscope along with energy dispersive spectroscopy. The influence of Mo variation in the CoCrNiTiMox high entropy alloy in phase formation and crystal structure is studied using the x-ray diffraction technique. The results reveal that the CoCrNiTiMox high entropy alloy possesses two BCC solid solution phases and the powder milled for 10 h is selected as the feedstock powder for plasma spray due to its morphology and good homogeneity of mixing. © 2022, ASM International.Item Analysis of light weight natural fiber composites against ballistic impact: A review(KeAi Publishing Communications Ltd., 2023) Doddamani, S.; Kulkarni, S.M.; Joladarashi, S.; Mohan Kumar, M.K.; Gurjar, A.K.The main factors in the ballistic impact mechanism, an incredibly complicated mechanical process, are the target material's thickness, toughness, strength, ductility, density, and projectile parameters. Creating resilient, high-strength, and high-modulus fibers has made it possible to use natural fibers and their composite laminates for various impact-related applications today. Kinetic energy absorption, penetration depth, and residual velocity were the parameters affecting the performance of natural fiber composites used in the armor systems. This review aims to comprehend the several influencing factors that significantly impact the target's ballistic impact performance. In addition to experimental study efforts, many analytical, numerical modeling, and empirical technique-based research approaches have also been considered while analyzing the various components. The paper also examines several factors that determine how well natural fiber composite functions, including internal factors like material composition, characteristics of matrix and reinforcement, the kind and choice of fiber/matrix, failure modes, impact energy absorption, and external factors such as residual velocity, and various projectile nose angles. It also emphasizes the ways to improve composites for high performance and ballistic efficiency, as well as the economic cost analysis of switching out synthetic fibers for natural ones in a ballistic composite. © 2023 The AuthorsItem Comprehensive review of modeling and material selection for hybrid sandwich composites for ballistic impact application using Six Sigma DMAIC methodology(SAGE Publications Ltd, 2025) Mohan Kumar, T.S.M.; Joladarashi, S.; Kulkarni, S.M.Natural fiber-based PMC (polymer matrix composites) have recently been increasingly popular because of their reduced product weight, low material costs, and renewable sources. Hybrid composites with different combinations of fibers/matrix are attracting interest from many manufacturing industries and researchers for various applications because of their specialized mechanical and impact properties. Hybridization is one of the most essential and indispensable strategies to improve composite material performance. Hybrid sandwich composites are reviewed to enhance the mechanical properties. They mainly concentrate on improving impact properties with increased energy absorption and penetration behavior, making them competent for advanced applications. The most time-consuming and challenging task is identifying the suitable composite material for a specific application. Selecting a suitable fiber and matrix is a difficult job for impact applications because the impact can cause severe damage to composite used in structural applications. The main objective of this review is to select suitable fiber and matrix combinations for impact application by exploring the literature gap. The Six Sigma DMAIC methodology provides a different approach to the selection of material. The benefit of this methodology is the choice of material has been made based on a twofold decision-making process that provides an accurate result. In addition to this blending, the qualitative approach (Pugh method) and the quantitative approach (Analytical hierarchy process) produce more accurate results during the comparison process, making it easier to choose the best material. © IMechE 2025.Item Experimental investigation on slurry erosive behaviour of biodegradable flexible composite and optimization of parameters using Taguchi's approach(Lavoisier, 2018) Mahesh, V.; Joladarashi, S.; Kulkarni, S.M.In the present study, the emphasis is on analysing the slurry erosive behaviour of novel green flexible composite made from jute fiber and natural rubber of ribbed smoke sheet (RSS) grade. The bonding gum made of natural rubber is used to bind the fiber and RSS rubber. Three different stacking sequences namely jute-rubber-jute (JRJ), jute-rubber-rubberjute (JRRJ) and jute-rubber-jute-rubber-jute (JRJRJ) are considered. Erosive studies are carried out on the prepared composites under three different rotation speeds (500, 1000 and 1500 rpm) and three different sand concentration (50, 75 and 100 gms) with silica sand as the abrasive medium dispersed in tap water. Design of experiments (DOE) is carried out using Taguchi's L9 orthogonal array on slurry erosion test to find out the effect of the stacking sequence, rotation speed and sand concentration on the weight loss of the composite. Through ANOVA, it was concluded that sand concentration is the main factor affecting the weight loss of composite. Regression model is developed and it was found that the developed model is adequate and feasible to predict the weight loss due to slurry erosion within the range of experimental conditions. © 2018 Lavoisier. All rights reserved.Item Influence of microwave hybrid heating on the sliding wear behaviour of HVOF sprayed CoMoCrSi coating(Institute of Physics Publishing helen.craven@iop.org, 2018) Prasad, C.D.; Joladarashi, S.; Ramesh, M.R.; Srinath, M.S.; Channabasappa, B.H.CoMoCrSi superalloy powder (Tribaloy-T400) consists of intermetallic laves phase and primary eutectic phase of Co-rich solid solution. Processing of Tribaloy-T400 powder is carried out through high-energy ball milling (HEBM) technique to obtain a higher volume fraction of intermetallic laves phases. The feedstock is sprayed using high-velocity-oxy-fuel (HVOF) process on titanium grade-15 substrate. The coating microstructure is homogenized by microwave hybrid heating technique. Characterization of feedstock, as-sprayed and microwave fused coatings is done by using Scanning Electron Microscopy (SEM), Energy dispersive spectroscopy (EDS) and x-ray Diffraction (XRD). Porosity, surface roughness, microhardness, and bond strength are measured. Adhesive wear behavior of the coatings under the dry sliding condition is evaluated at an applied load of l0 and 20 N and temperature of 200, 400 and 600 °C Fused coating exhibit higher wear resistance than the as-sprayed coatings and substrate. The hard intermetallic laves phases which are amorphous (bulk metallic glass) in nature strengthen the coating at high temperatures. © 2018 IOP Publishing Ltd.Item Hygrothermal coupling analysis of magneto-electroelastic beams using finite element methods(Taylor and Francis Ltd. michael.wagreich@univie.ac.at, 2018) Mahesh, M.; Kattimani, S.C.; Joladarashi, S.In this article, the finite element (FE) method has been used to assess the coupled static behavior of hygro-thermo-magneto-electroelastic (HTMEE) beam. Influence of externally applied hygrothermal loads on the direct (displacements, electric and magnetic potentials) and derived quantities (stresses, electric displacement and magnetic flux densities) of HTMEE beam have been studied in detail. The principle of total potential energy and the coupled constitutive equations of HTMEE material are used for the FE formulation. A generalized condensation technique is adopted to solve the global FE equations of motion. Numerical examples are discussed to examine the effect of hygrothermal loads and distinct effect of moisture concentration on the behavior of the beam. Particular emphasis has been placed to analyze the influence of temperature and moisture dependent elastic stiffness coe?cients associated with empirical constants. Considering the independent effect of temperature and moisture on the coupled static responses, the most significant combination of the empirical constants corresponding to temperature dependency and moisture dependency are explored. Extensive computational examples are considered to examine the significant effect of boundary conditions, temperature gradient, moisture concentration gradient and empirical constants on the static behavior of HTMEE beam. It is observed that the static behavior of HTMEE beam is significantly influenced by the hygrothermal loads and empirical constants. The results presented in this article would serve as a benchmark results in design and analysis of HTMEE structures for sensors and actuators applications. © 2018 Taylor & Francis.Item Investigation on the eect of using rubber as core material in sandwich composite plate subjected to low-velocity normal and oblique impact loadings(Sharif University of Technology, 2019) Mahesh, V.; Joladarashi, S.; Kulkarni, S.M.In this article, the structural performance of composite plate under low-velocity impact is studied. Two forms of layup sequence, namely, Jute-Epoxy laminate (JE) and Jute-Epoxy-Rubber sandwich (JE-R-JE), were considered for evaluation. Special emphasis was on evaluating the inuence of normal and oblique loadings. Various dynamic parameters, such as energy, peak load, and deformation, were analysed in detail to study the eect of impact angle on both laminate and sandwich structures. Stress analysis of both laminate and sandwich structures was carried out to discuss the eect of introducing rubber as a core material. The results revealed that using rubber as a core material had a signicant eect on energy absorption. In addition, it was noticed that increasing the angle of impact would yield better performance of the composite plate. The results presented here may serve as benchmark for eective utilization of composite plates in low-velocity impact applications. © 2019 Sharif University of Technology. All rights reserved.Item Physio-mechanical and wear properties of novel jute reinforced natural rubber based flexible composite(Institute of Physics Publishing helen.craven@iop.org, 2019) Mahesh, V.; Joladarashi, S.; Kulkarni, S.M.This paper deals with the design, fabrication, physio-mechanical and wear characterization of the composites prepared from naturally available jute fiber and rubber matrix materials. Jute and natural rubber are cost effective, abundant and environmental friendly materials which can be used as fiber and matrix respectively. The flexible composite with different stacking sequence are manufactured using compression moulding machine and void percentage, water absorption percentage, tensile properties, tear strength, impact strength and shore hardness of the prepared composites are found along with the wear. The void content and water absorption are found to increase with increased number of plies in the composite with fibers contributing more compared to rubber. Tensile, tear, specific wear rate and hardness are found to better with a composite having minimum number of plies, which is JRJ. Charpy impact test revealed that the variation in specific impact strength of the three configuration of composites are negligible and no failure of composites were absorbed owing to their flexibility indicating all the three composites have additional capability to absorb much higher energy and suitable as sacrificial components for structural applications subjected to low velocity impact. The fractography analysis of tensile and tear test shows that the flexible composites are free from matrix cracking, but matrix tearing plays a vital role in failure. The mechanism of wear involved in the proposed composites when different constituents of the composite are exposed to abrasive medium is studied through surface morphology. © 2019 IOP Publishing Ltd.Item Experimental study on Abrasive wear behaviour of flexible green composite intended to be used as Protective Cladding for Structures(ModTech Publishing House office@hotelfloramamaia.ro, 2019) Mahesh, V.; Joladarashi, S.; Kulkarni, S.M.In the present study, the influence of material and process parameters on the two body abrasive wear behavior of Jute-Rubber flexible composite is investigated using Taguchi’s design of experiments (DOE). Three different stacking sequences of composite namely jute-rubber-jute (JRJ), jute-rubber-rubber-jute (JRRJ) and jute-rubber-jute-rubber-jute (JRJRJ) are considered and their wear behavior is evaluated using two body abrasion test with multi-pass condition for abrading distances of 0.4 m to 1.2 m in increments of 0.4 m and varied load of 9.81 N, 12.26 N and 14.71 N. Abrasive volume loss and specific wear rate as function of abrading distance are determined. The results from Taguchi’s design of experiments show that for two body dry sliding wear situation, an abrading distance significantly affects the specific wear rate compared to load and composite configuration. However, volume loss is more and appreciable when jute fabric is exposed to abrasive medium rather than when the rubber is exposed. Surface morphology study is carried out using a scanning electron microscope to get an insight of wear mechanism of constituents of the flexible composite. Stretching of asperities results in wear of the rubber, whereas fiber breakage causes wear of the jute. Rubber being the dominating constituent of flexible composite results in providing better wear resistant properties and thus can act as a potential candidate for sacrificial structures to protect primary structures subjected to wear. © International Journal of Modern Manufacturing Technologies.