Kumar M.A.,GATES Institute of Technology |
Ramachandra Reddy G.,Sri Krishnadevaraya University |
Ramesh A.,GATES Institute of Technology |
Nanjunda Reddy Bh.,Amrita University |
Sanjeev Kumar P.,Siddartha Educational Academy
Pakistan Journal of Scientific and Industrial Research Series A: Physical Sciences | Year: 2012
Tensile and flexural properties of coconut shell particulate reinforced polyester resin matrix based composites were evaluated to assess the possibility of using these filler as a new eco-friendly material in engineering applications. Composites were made out of the function of coconut shell powder with different weight variations viz. 10, 15, 20, 25 and 30 wt %, treated with 5% NaOH alkali solution and these were prepared by hand lay-up process. Performance was increased gradually as filler content increased from 10 to 25 wt %. On the other hand decline of the properties were observed when filler content was beyond 25 wt %, heat deflection temperature (HDT) increased up to certain percentage (i.e. 25 wt %) of filler in polyester above which no influence in its value was observed. The glass transition temperature (Tg) and thermal stability was improved significantly. Scanning electron microscopy (SEM) micrographs were also studied to illustrate the particle/matrix interactions. These composites were further subjected to an evaluation ofthermogravimetric, differential scanning calorimetry, and heat deflection temperature (HDT) analysis.
Reddy N.N.,Italian Institute of Technology |
Ravindra S.,University of South Africa |
Reddy N.M.,Gates Institute of Technology |
Rajinikanth V.,University of South Africa |
And 2 more authors.
Journal of Magnetism and Magnetic Materials | Year: 2015
The present work deals with the development of temperature and magnetic responsive hydrogel networks based on poly (N-isopropylacrylamide)/acrylamido propane sulfonic acid. The hydrogel matrices are synthesized by polymerizing N-isopropylacrylamide (NIPAM) monomer in the presence of acrylamido propane sulphonicacid (AMPS) using a cross-linker (N,N-methylenebisacrylamide, MBA) and redox initiating system [ammonium persulphate (APS)/tetramethylethylenediamine (TMEDA)]. The magnetic nanoparticles are generated throughout the hydrogel networks using in situ method by incorporating iron ions and subsequent treatment with ammonia. A series of hydrogel-magnetic nanocomposites (HGMNC) are developed by varying AMPS composition. The synthesized hydrogel magnetic nanocomposites (HGMNC) are characterized by using Fourier Transform Infrared (FTIR) Spectroscopy, X-ray diffraction (XRD), Thermal Analyses and Electron Microscopy analysis (Scanning and Transmission Electron Microscope). The metal extraction capacities of the prepared hydrogel (HG) and hydrogel magnetic nanocomposites (HGMNC) were studied at different temperatures. The results suggest that HGMNCs have higher extraction capacity compared to HG and HG loaded iron ions. This data also reveals that the extraction of metals by hydrogel magnetic nanocomposites (HGMNCs) is higher at higher temperatures than room temperature. The prepared HGMNCs are also subjected to hyperthermia (cancer therapy) studies. © 2015 Elsevier B.V. All rights reserved.
Sai Chaitanya Kishore D.,GATES Institute of Technology |
Prahlada Rao K.P.,Jawaharlal Nehru University |
Ramesh A.,GATES Institute of Technology
Materials Today: Proceedings | Year: 2015
Al6061- TiC composite with 4 wt% TiC was produced by the reaction of halide salt K2TiF6 and C with the molten aluminum. SEM and EDX tests were performed to know the presence of the TiC reinforcement. Vickers micro hardness test was done and find that the hardness of Al6061 was increased by the addition of TiC. Machinability study was performed on the in-situ Al6061-TiC MMC to study the effect of cutting speed, feed and depth of cut on cutting force and surface roughness by using Taguchi L-27 orthogonal array. ANOVA is performed on the obtained results to investigate the contribution of cutting speed, feed and depth of cut on cutting force and surface roughness. © 2015 Elsevier Ltd.
Reddy T.R.K.,SRIT Engineering College |
Rao T.S.,Sri Krishnadevaraya University |
Suvarna R.P.,Jawaharlal Nehru Technological University Anantapur |
Kumar M.A.,GATES Institute of Technology
Proceedings of the International Conference on "Advanced Nanomaterials and Emerging Engineering Technologies", ICANMEET 2013 | Year: 2013
In this paper the tensile strength and modulus of cow dung powder filled glass- polyester hybrid composites were studied. Two different hybrid composites such as treated and untreated cow dung fibers were fabricated and effect of alkali treatment of the cow dung fibers on these properties were studied. It was observed that, tensile strength and modulus of the hybrid composites increases with increase of cow dung percentage of weight. These properties found to be higher when alkali treated cow dung fibers were used in the hybrid composites. The eradication of amorphous hemi-cellulose with alkali treatment leading to higher crystalline of the cow dung fibers with alkali treatment might responsible for these observations. The effect of alkali treatment on the bonding between glass / cow dung composites was also studied. Scanning electron microscope (SEM) was also conducted on the cross sections of fractured surfaces. © 2013 IEEE.
Kumar G.B.V.,Amrita University |
Swamy A.R.K.,Dr. M.G.R. Educational and Research Institute |
Swamy A.R.K.,Acharya Institute of Technology |
Ramesha A.,GATES Institute of Technology
Journal of Composite Materials | Year: 2012
Aluminum (Al) alloys started replacing cast iron and bronze alloys in the manufacture of wear-resistant parts and are materials of interest owing to their low density, higher strength to weight ratio, which is an additional advantage in aerospace, marine and automotive applications. Al-metal matrix composite (MMC) materials are very much popular due to the reason that these composites possess good mechanical properties and higher wear resistance. This article is aimed to present the experimental results of microstructure, hardness, tensile, yield and compression strength, percentagage elongation, volumetric wear loss, and wear rate of Al6061-Tungsten Carbide (WC)-Graphite (Gr) reinforced hybrid MMCs. The composites were prepared using the liquid metallurgy technique, in which 0 to 4 wt% of WC particulates were dispersed into the matrix alloy in steps of 1 wt% by maintaining the Gr to 4 wt% constant. The experimental results indicate that the density of the hybrid-MMCs increases with increased WC content and further, agree to the values obtained through the rule of mixtures. The physical, mechanical and the tribological properties of the Al6061-WC-Gr hybrid MMCs were found to increase with increased WC content in the matrix at the cost of reduced ductility. The WC and Gr reinforcements contributed significantly in improving the wear resistance of Al6061-WC-Gr hybrid MMCs. © 2011 The Author(s).
Ramachandra Reddy G.,Sri Krishnadevaraya University |
Ashok Kumar M.,GATES Institute of Technology |
Karthikeyan N.,GATES Institute of Technology |
Mahaboob Basha S.,Mechanical Section
Mechanics of Advanced Materials and Structures | Year: 2015
Polyester-based hybrid composites were developed by combining the tamarind fruit (Tf) and glass fibers into a polyester matrix. Hardness, impact strength, frictional coefficient, and chemical resistance of hybrid composites with and without alkali treatments were studied. Variation of the aforementioned mechanical properties and chemical resistance was studied with different fiber lengths, such as 1, 2, and 3 cm. A 9 vol% of the tamarind and glass fibers was reinforced into the polyester matrix. The aforementioned mechanical properties were optimally improved at 2-cm fiber length when compared with 1- and 3-cm fiber lengths. Chemical resistance was also significantly improved for all chemicals except toluene. A 3°C rise in decomposition temperature while a 2°C rise in glass transition temperature was observed from TGA and DSC micrograms, respectively. Copyright © Taylor & Francis Group, LLC.