Faculty Publications
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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 Tribo-mechanical and physical characterization of filament wound glass/epoxy composites(Institute of Physics Publishing helen.craven@iop.org, 2019) Biradar, S.; Joladarashi, S.; Kulkarni, S.M.The present research aims to investigate mechanical, physical and tribological properties of filament wound Glass Fibre Reinforced Polymer (GFRP) composite pressure vessel as per respective ASTM standards. Here test coupons prepared from GFRP vessel are subjected to tensile, compression, flexural and impact testing to investigate mechanical properties. The physical properties are studied from density, ignition loss and water absorption tests. The tribological study was carried out using abrasive slurry erosion tester. All tests carried out in this study are as per respective ASTM standard. The results obtained from various mechanical testings are satisfactory and also almost equal in strength with respect to metallic pressure vessels. Particularly from impact testing, the strength of sea water treated sample has considerably increased. Fractography study was conducted on failed samples to study various mode of failure in detail. The physical characterization has elaborated the behavior of filament wound GFRP material under moisture environment which has observed a maximum of 0.5% water absorption rate. As per ignition loss study which reveals about 95%-98% weight of ignition loss is recorded, which indicates perfect fibre to resin ratio and almost nil or least % of void content. The slurry erosion test results are within the expected range and maximum wear of 9.67% is recorded under extreme case. The overall study reveals that the presence of voids, non-uniform distribution of fibre and matrix have an impact on the outcomes of many mechanical properties. From the above study we can conclude that filament wound GFRP pressure vessel can be used in many applications since it is a non-hydrophobic, better wear resistant and several strength parameters have also improved or unaltered under rigorous testing conditions. © 2019 IOP Publishing Ltd.Item Influence of weave pattern and composite thickness on mechanical properties of bamboo/epoxy composites(Institute of Physics Publishing helen.craven@iop.org, 2019) Kanaginahal, G.M.; Hebbar, H.S.; Kulkarni, S.M.The results of an attempt made for studying the influence of weave pattern and composite thickness of plain and twill weave bamboo fabric reinforced epoxy/phenalkamine composites on static mechanical properties are reported in this paper. Plain weave and Twill weave bamboo fabric of 125 gsm were used as reinforcements with medium viscous epoxy B-11 resin and highly viscous AI 1041 phenalkamine bio-based hardener. Thickness of composite achieved were 3.1, 4.3 and 5.4 mm with fiber weight fraction at 18% by hand layup method. The aim was to study the influence of weave pattern and thickness of composite on the tensile, flexural and impact properties. Fourier Transform Infra-Red results showed the presence of cellulose, polysaccharides, cardanol groups and hydrogen bonding of reinforcement and matrix. X-Ray Diffraction peaks displayed higher intensities for twill weave fabric. Tensile studies of fabrics showed 7% higher strength for twill weave compared to that of plain weave fabric in warp direction. Twill weave composites with 5.4 mm thickness showed an increase of 12% in tensile strength and 8% increase in stiffness compared to plain weave composite of same thickness. Twill weave composite with 5.4 mm thickness showed an increase of 22% in flexural strength and 28% in stiffness compared to plain weave composite of same thickness. Izod impact results displayed an increase of 16% in absorbed energy for 5.4 mm thickness twill weave composite when compared with plain weave composite of same thickness. Fractography of fractured specimens of tensile test displayed fiber pullouts for plain weave composites and fiber breakage for twill weave composites. Twill weave composites have shown better wettability than that of plain weave composites. © 2019 IOP Publishing Ltd.Item Tribo-mechanical characterization and optimization of green flexible composites(ICE Publishing, 2020) Mahesh, V.; Joladarashi, S.; Kulkarni, S.M.The use of natural fibers as a substitute for synthetic fibers as reinforcement in polymer-based composites is finding prominence nowadays. The present paper deals with the comparative study of biodegradable flexible composites fabricated using jute fabric and rubber with different configurations-namely, jute/rubber/jute (JRJ), jute/rubber/rubber/jute (JRRJ) and jute/rubber/jute/rubber/jute (JRJRJ)-using their tribo-mechanical properties as the attributes and making use of a multi-attribute decision making (MADM) approach-namely, technique for order of preference by similarity to ideal solution (Topsis). The tensile strength, tear strength, interlaminar shear strength and specific wear rate of the proposed composites are chosen as the attributes for comparison using Topsis. The results show that JRJRJ is the best configuration among the considered configurations of flexible composites, providing the overall best tribo-mechanical properties, and the fractography study shows that the proposed flexible composites undergo failure mainly due to matrix tearing in the case of tensile and tear tests as opposed to matrix cracking in the case of stiff composites. Also, the wear study reveals that rubber exhibits better resistance to wear. This study shows the efficient application of the statistically based MADM tool Topsis for material selection. © 2020 ICE Publishing: All rights reserved.Item Development of Sustainable Jute/Epoxy Composite and Assessing the Effect of Rubber Crumb on Low Velocity Impact Response(Taylor and Francis Ltd., 2022) Mahesh, V.; Mahesh, V.; Harursampath, D.; Joladarashi, S.; Kulkarni, S.M.In the current study, the experimental assessment of influence of rubber crumb on the low velocity impact (LVI) behavior of jute epoxy composites are carried out using two types of impactors namely hemispherical and conical. Hand layup technique is used to fabricate the proposed composites. The rubber crumb is incorporated in the epoxy resin with 1.5 wt%, 3 wt%, and 5 wt%. Results revealed that incorporation of 3 wt% of rubber crumb resulted in better LVI response compared to its counterparts. Fractography studies revealed that inclusion of rubber crumb particles enhances the adhesion between resin and fiber, thereby increasing the energy absorption. In addition, they aid in reducing damage area and increasing penetration threshold of proposed composites. The current study’s systematic technique serves as a model for the efficient use and conversion of waste rubber crumb into usable natural fiber reinforced polymer matrix composites for LVI applications. © 2022 Taylor & Francis.Item Mode-I fracture behaviour of aramid/glass-epoxy interply hybrid composites(SAGE Publications Ltd, 2025) Kanakannavar, S.; Biradar, S.; Hiremath, S.; Rajole, S.; Pitchaimani, J.; Kulkarni, S.M.; Goh, K.-L.This article presents the influence of hybridisation of aramid and glass fibre woven fabric on fracture toughness (KIC) of the composites. Experiments using single-edge-notched-bending (SENB) were conducted to investigate the hybridisation effect on the Mode I fracture toughness specimen of aramid/glass laminates. The results revealed that the aramid epoxy composites yielded the highest KIC, followed by aramid/glass epoxy hybrid composites, and finally, glass epoxy composites, which exhibited the lowest KIC. Fracture micrographs of the hybrid composites showed similar fracture patterns – fibre pullout, fibre rupture and matrix rupture – to those of the aramid and glass epoxy composites. The mechanical properties of the hybrid composites being inferior to those of the aramid epoxy composites suggest that there is no advantage in using glass fibres to partially replace aramid fibres in achieving hybrid composites. © The Author(s) 2025Item Enhancing tool longevity through TiN coating in multistage cold forging: implementation and analysis using Archard’s wear theory and FEA(Springer-Verlag Italia s.r.l., 2025) Kulkarni, V.P.; Kulkarni, S.M.; Patil, S.B.; Anshul, A.Multistage cold forging is widely used in manufacturing; however, high punch wear limits tool life, increasing operational costs and downtime. This study examines the effect of Titanium Nitride (TiN) coating on punch life in multistage cold forging using Archard’s wear theory and Finite Element Analysis (FEA). The research addresses challenges related to tool wear and premature failure, which impact production efficiency, by comparing the punch life of uncoated and TiN-coated punches under identical forging conditions. Archard’s wear theory describes the progressive wear behavior of TiN-coated punches, while FEA simulations with Simufact Forging provide detailed visualizations of stress distributions, wear hotspots, and failure mechanisms. The results show a significant improvement in punch life with TiN-coated punches, where the uncoated punch lasted 9,520 strokes, and the TiN-coated punch lasted 18,051 strokes, representing an increase of approximately 89.6%. Further FEA analysis corroborated these findings, predicting 9,622 strokes for the uncoated punch and 19,496 strokes for the TiN-coated punch.These findings confirm that TiN coatings effectively enhance tool durability, reduce wear, and optimize cold forging processes, thereby reducing operational costs and improving overall efficiency. © The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature 2025.