Journal Articles
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Item Friction and dry sliding wear behaviour of Ni filled epoxy nanocomposite(2011) Kurahatti, R.V.; Suredranathan, A.O.; Kori, S.A.; Ramesh Kumar, A.V.; Mordina, B.; Mallapur, D.G.Nanosized metal particle filled polymer composites are finding numerous tribological applications in recent years. In the present work, the matrix properties were investigated by introducing nickel nanoparticles (60-100 nm, filler content of 0?5-10 wt-%) into epoxy resin. The influence of these particles on friction and dry sliding wear behaviour was measured using a pin on disc wear set-up. The experimental results indicated that the coefficient of friction and the specific wear rate of epoxy resin can be reduced with a rather low weight fraction of Ni particles. The lowest specific wear rate of 0?6461024 mm3 N21 m21 (compared to neat resin's value of 2?261024 mm3 N21 m21) was observed for composites with the filler content of 0?5 wt-%. The reinforcement of Ni particles leads to improved mechanical properties of the epoxy composites. The results have been supplemented with scanning electron micrographs to help understand the possible wear mechanisms. © 2011 W. S. Maney & Son Ltd.Item Comparison of structural health assessment capabilities in epoxy - Carbon black and epoxy - Carbon nanotube nanocomposites(2014) Inam, F.; Badekai Ramachandra, B.; Luhyna, N.; Vo, T.A novel method for comparing structural health of different types of brittle epoxy nanocomposites filled with carbon nanostructured fillers is presented. Epoxy - 0.2 vol% carbon black (CB) and epoxy - 0.2 vol% carbon nanotube (CNT) nanocomposite bars were prepared by calendering and thermal curing. Nanocomposite bars were subjected to Vickers diamond indentation to produce sub-surface damage. Electrical conductivities were analysed by 4-point method to estimate the structural damage caused by indentation. For comprehensive comparison, fracture toughness and percolation threshold were analysed as well. Because of the systematically induced indentation damage, a sharp decrease of 89% was observed in the electrical conductivity of epoxy - CNT nanocomposite as compared to 25% in the electrical conductivity of epoxy - CB nanocomposite. CNTs impart superior damage sensing capability in brittle nanocomposite structures, in comparison to CB, due to their high aspect ratio (fibrous nature) and high electrical conductivity. © BME-PT.Item Mechanical properties and sliding wear behavior of jatropha seed cake waste/epoxy composites(Springer Japan, 2015) Shivamurty, B.; Murthy, K.; Joseph, P.C.; Rishi, K.; Bhat, K.U.; Anandhan, S.Jatropha seed cake particulate (JSCP)-reinforced epoxy composites were prepared by open mold resin casting method. The influence of JSCP on mechanical and dry sliding wear properties of epoxy was experimentally investigated as per the ASTM standards. Dry sliding wear test was conducted for these composites at a constant sliding distance of 500 m with different sliding velocities and applied loads by a pin-on-disc wear test machine. The results revealed that incorporation of JSCP decreased the specific wear rate and coefficient of friction while improving the mechanical properties. The composite reinforced with 40 wt% of JSCP exhibited better mechanical properties and wear behavior compared to the neat epoxy and other compositions of JSCP/epoxy composites. The results of this study indicate that jatropha seed cake powder can be used as biosolid lubricant filler for epoxy. © 2014, Springer Japan.Item A Study on Areca nut Husk Fibre Extraction, Composite Panel Preparation and Mechanical Characteristics of the Composites(Springer, 2019) Muralidhar, N.; Kaliveeran, V.; Arumugam, V.; Srinivasula Reddy, I.Areca nut husk fibre is an agricultural waste, which does not contribute to the economy of areca nut plantation. The use of areca nut husk fibre as reinforcing material in the preparation of low-cost and lightweight composites provides utility value to areca nut husk fibre. Low-cost and lightweight composites have wide range of applications in construction industry, marine structures, automobile industry and aerospace industry. The present work focuses on extraction of areca nut husk fibre with alkali treatment process by using 6% of sodium hydroxide solution, composite panel preparation and determination of mechanical properties of composite panels. Different fibre compositions (fine fibre, coarse fibre and coarse fibre sandwiched with glass fibre) of 15% by weight were used in the present study. Tensile, flexural and impact tests were conducted to find the mechanical characteristics the composite materials. The tensile strength of composites made with fine fibre (15.1 MPa) is observed to be more than that of composites made with coarse fibre (10.8 MPa). Further improvement in tensile strength of composite panels made of coarse areca nut husk fibre layer sandwiched with two layers of glass fibre (24.8 MPa) is observed. The flexural strength of fine fibre composites is more when compared to that of the coarse fibre composites. The average flexural strength of composites reinforced with fine fibre, coarse fibre and coarse fibre sandwiched with glass fibre is observed as 73 MPa, 66.7 MPa and 284 MPa, respectively. The impact strength of coarse fibre composites is found to be higher when compared to that of fine fibre composites. © 2019, The Institution of Engineers (India).Item Influence of textile properties on dynamic mechanical behavior of epoxy composite reinforced with woven sisal fabrics(Springer, 2020) Nagamadhu, M.; Jeyaraj, J.; Mohan Kumar, G.C.Due to low cost and environmentally friendly characteristics, natural fibers gain much attention over synthetic fiber. The aim of the present work is to characterize the textile properties of three different types of sisal fabric and study dynamic mechanical properties and water absorption behavior of the sisal fabric reinforced epoxy composite. Influence of grams per square meter of fabric, weaving pattern of the fabric on textile properties of the fabric is studied first. Further, the effect of the same on the dynamic mechanical properties of the sisal composites is studied. Effect of fiber weight percentage and dynamic frequency on dynamic mechanical properties also studied. Results reveal that the storage modulus (G?) decreases with increasing temperature in all the woven types of composites under consideration. However, Plain 2 (P2) and Weft Rib (WR) composites have shown better values of G? even after the glass transition temperature (Tg). From the results, it is also evident that storage and loss modulus (G??) increases when the yarn diameter decreases which is observed at a higher temperature also. It is also observed that fabric density also plays a significant role in the enhancement of G? and G?? values. The water absorption of Plain 1 (P1) based composites are found to be less compared to the other types of composites analyzed. © 2020, Indian Academy of Sciences.Item Structure-property relationship of glass fabric/MWCNT/epoxy multi-layered laminates(Elsevier Ltd, 2020) Shivamurty, B.; Anandhan, S.; Bhat, K.U.; Thimmappa, B.H.S.Neat glass fabric/epoxy composites (GECs) and multi-wall carbon nanotube/glass fabric/epoxy composites (MWCNTGECs) were prepared by hand-lay-up followed by compression molding technique and investigated the structural properties. It is found that the mechanical properties and wear resistance of the glass fabric reinforced epoxy composite improved upon the addition of MWCNTs. The 0.3 wt%MWCNTs filled glass fabric/epoxy composite (0.3MWCNTGECs) exhibits better properties as compared to 0.075 wt% MWCNT filled glass fabric/epoxy composites (0.075MWCNTCs), 0.15 wt% MWCNT filled glass fabric/epoxy composites (0.15MWCNTCs) and GECs. The mechanism of wear failure of these composites was analyzed from the morphology of worn surfaces. It was observed solid lubricant film established on the wear track at higher normal loads reduces the wear. The correlation of Vickers's hardness and Lancaster factor (?e)?1 with specific wear rate is investigated and reported. © 2020Item An experimental investigation of epoxy-based hybrid composites with hexagonal boron nitride and short sisal fiber as reinforcement for high performance microelectronic applications(John Wiley and Sons Inc, 2022) Agrawal, A.; Chandraker, S.In the present article, an investigation is presented on epoxy-based composites where the discontinuous phases are microsized boron nitride and sisal fiber (SF). Both the reinforcing materials are surface modified before incorporating them into the epoxy matrix. Hexagonal boron nitride (hBN) surface is treated by silane-coupling agent, whereas the aqueous NaOH solution is used to modify the surface of SF. The effect of fillers on the physical, mechanical, thermal, and dielectric properties of hybrid composites is studied through experimentation. The result shows that the inclusion of hBN increases the thermal conductivity of epoxy appreciably and dielectric constant marginally, while the inclusion of SF reduces the thermal conductivity marginally and dielectric constant appreciably. The maximum thermal conductivity of 1.88 W/m-K is obtained for the combination of 30 wt% hBN and 3 wt% SF. For the same combination, the dielectric constant is 4.57 at 1 GHz, which is almost similar to neat epoxy. Also, other properties like compressive strength, hardness, glass-transition temperature, and coefficient of thermal expansion improve when combinations of ceramic filler and natural fiber were incorporated in the epoxy matrix. Due to outstanding comprehensive properties, epoxy/hBN/SF composites found potential application in wide microelectronic applications. © 2021 Society of Plastics Engineers.Item Friction and wear study of graphite and bronze filled epoxy matrix composites(Elsevier Ltd, 2022) Patil, N.; Krishna, P.The composite material is made of different materials. It retains the advantages of the original material and reflects combined characteristics of all the constituents. Polymer matrix composites are popular in the recent industrial applications. Friction and wear governs the tribological aspects of polymer composites. This paper revel the experimental study of friction and wears behavior of epoxy composites filled with bronze and graphite fillers as per ASTM standards. Three compositions were studied and it was found that composition ‘A’ has lowest coefficient of friction (0.281) whereas composition ‘C’ has highest coefficient of friction (0.325). The composition ‘A’ has lowest wear rate of 0.5 μm/s and composition ‘C’ showed highest wear rate of 3.25 μm/s. Use of graphite and bronze along with epoxy exhibited formation of lubricating layer and enhanced friction and wear behavior of the composites. © 2021Item Development and Characterization of Epoxy-Based Polymeric Composite with Bio-particulates as Filler Material(Springer Science and Business Media Deutschland GmbH, 2022) Chandraker, S.; Dutt, J.K.; Agrawal, A.; Roy, H.; Rajkumar; Chandrakar, K.; Mishra, V.The focus of this paper is to develop cheap and unconventional materials for both structural and non-structural applications using eco-friendly bio-wastes. The study used pistachio nutshells (normally disposed of as waste) for fabricating bio-particulate-based polymeric composites. In this investigation, epoxy is taken as matrix material and pistachio nutshells in the form of microparticles are used as filler material. Six different sets of composites with varying filler content up to a maximum of 30 wt% are fabricated by a hand lay-up method. The excellent compatibility and bonding between the matrix and filler material under investigation are confirmed by micrograph obtained from scanning electron microscopy and by Fourier-transform infrared spectroscopy analysis. Physical and mechanical properties are evaluated experimentally as per ASTM. Apart from that, a linear viscoelastic semi-solid model is reported here to understand the mechanical dynamic behaviour of the developed material. On the basis of several test result, the developed composite may find its potential application in light-duty structures efficiently. © 2021, King Fahd University of Petroleum & Minerals.Item Probing the effect of post-curing and halloysite nanotube reinforcement on thermo-mechanical properties of lightweight epoxy syntactic foam composites(SAGE Publications Ltd, 2023) Bakshi, M.S.; Kattimani, S.This paper deals with an investigation of the post-curing effect of halloysite nanotubes (HNTs) reinforced syntactic foam (HRSF) containing cenosphere as hollow inclusion at 0, 20, and 40 vol% in an epoxy matrix. Compression, flexural, and thermal properties of HRSF (1 vol% HNTs) and cenosphere/epoxy syntactic foam (CESF) composites without HNTs are studied under the influence of post-curing. Further, the post-cured HRSF containing 40 vol% cenosphere (NSF40_H) exhibited a compressive modulus of 33.2% higher than room temperature cured neat epoxy due to improved crosslinking. Addition of HNTs in NSF40_H augments the flexural modulus up to 26.9% compared to post-cured neat epoxy. Additionally, the glass transition temperature (Tg) of CESF composites with 40 vol% cenosphere was increased by 24.3 °C compared to the room temperature cured sample. This positive shift in Tg can be attributed to the beneficial impact of post-curing, as indicated by differential scanning calorimetry study. Thermogravimetric results demonstrated better thermal stability of HRSF relative to CESF and neat epoxy composites. Transmission electron microscopy illustrated the structure-property correlations of nanotube reinforcement. The improved properties of syntactic foams could be viewed as a potential material for lightweight constructions, especially in the marine and automobile industries. © IMechE 2022.