40 research outputs found

    Animal fiber characterization and fiber loading effect on mechanical behaviors of sheep wool fiber reinforced polyester composites

    Get PDF
    © 2020 Taylor & Francis. This is an Accepted Manuscript of an article published by Taylor & Francis in Journal of Natural Fibers on 06/12/2020, available online: https://doi.org/10.1080/15440478.2020.1848743.This study presents animal fiber characterization and the influence of various fiber loadings on mechanical properties of sheep hair fiber-reinforced polymer (SHFRP) composites. The sheep hair fibers (SHF) characterization was carried out using X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FTIR), thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM) and non-contact surface roughness machine. The functional group and chemical bond were analyzed using FTIR techniques. The crystallinity index and thermal stability of the SHF were characterized, using XRD and TGA techniques, respectively. The composites were fabricated using a compression molding technique and a varying weight percentage of 20, 30 and 40 fiber. The composite plates were cut into test samples according to ASTM standard methods for their mechanical (tensile, flexural and impact) behaviors to be extensively analyzed. The surface morphology of the fractured samples was examined with aid of an SEM. From the results obtained, it was evident that the SHFRP composite recorded a significantly increased tensile strength property when fiber loading was increased from 20 to 40 wt%. The optimum 40 wt% SHFRP composite sample recorded better flexural and impact strength, when compared with other counterparts. This was attributed to a better fiber-matrix interfacial adhesion, as established fromSEM micrographs.Peer reviewedFinal Accepted Versio

    A Novel Signal Processing Method for Friction and Sliding Wear

    Get PDF
    © 2021 by ASME. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1115/1.4052063This current study proposed a new computationally efficient and comparatively accurate algorithm for calculating both static and dynamic coefficients of friction from high frequency data. Its scope embraced an application in a real-time friction-based system, such as active braking safety systems in automobile industries. The signal sources were from a heavy-duty reciprocating dry sliding wear test platform, focused on experimental data related to friction induced by stick-slip phenomena. The test specimen was a polytetrafluoroethylene (PTFE)-coated basalt/vinyl ester composite material, tested at a large scale. The algorithm was primarily aimed to provide scalability for processing significantly large tribological data in a real-time. Besides a computational efficiency, the proposed method adopted to evaluate both static and dynamic coefficients of friction using the statistical approach exhibited a greater accuracy and reliability when compared with the extant models. The result showed that the proposed method reduced the computation time of processing and reduced the variation of the absolute values of both static and dynamic frictions. However, the variation of dynamic friction was later increased at a particular threshold, based on the test duration.Peer reviewe

    Effects of sand and gating architecture on the performance of foot valve lever casting components used in pump industries

    Get PDF
    Funding Information: The authors thank Kalasalingam Academy of Research and Education, Krishnankoil for providing the facilities for various tests and characterizations. The King Saud University authors extend their appreciation to the Deanship of Scientific Research at King Saud University for funding the work through the research group project no. RG-148. This Research was funded by King Mongkut's University of Technology North Bangkok has received funding support from the National Science, Research and Innovation Fund (NSRF) (Grant No. KMUTNB-MHESI-64-16.1). Publisher Copyright: © 2021 The Author(s)This work addresses manufacture, testing and simulation of foot valve lever (FVL) for monoblock pump industry, using a cost-effective casting design process. The impact of different types of sands, such as air-set, dry and sodium silicate as well as gating designs, namely H-, U- and O-type, were studied with respect to surface roughness and porosity. The mold pattern was produced using additive manufacturing (AM) technology. Both experimental and numerical investigations were performed on the temperature distribution of molten metal at random locations for the different gating configurations or designs, considering mold filling and solidification. It was evident from the experimental investigation that contribution of air-set sand and O-type gating architecture showed limited consistency effects. Importantly, gating architecture was the most influential parameter to determine all specified quality outcomes, independent of sand mold. An order of O < H < U-type was obtained from the gating designs for minimal surface roughness and percentage of porosity. Furthermore, the microstructure analysis depicted only an irregular defect with minimum quantity at both surface and cross-section of O-type at two different locations. Optimum pouring temperatures of 740, 750 and 790 °C were obtained for mold filling of all 24 components of H-, O- and U-type of gating designs, respectively. The varying solidification temperature was observed from real time thermocouple reading, which was in close agreement with the numerical simulation. Evidently, O-type of gating design exhibited best performance for large-scale development of the FVL in terms of surface roughness, porosity and cooling effects.Peer reviewe

    Effect of chemical treatment on physico-chemical properties of a novel extracted cellulosic Cryptostegia grandiflora fiber

    Get PDF
    © 2023 The Author(s). Published by IOP Publishing Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/The increasing global need to achieve sustainability in product development demands the use of biodegradable materials from renewable resources in many engineering applications. Accordingly, various natural fibers were explored as suitable reinforcement in polymer matrixes due to their low density and biodegradability. Hence, in this present work, a novel fiber reinforcement was extracted from the stem of the Cryptostegia grandiflora (CG) plant through a retting process and manual intervention. The extracted Cryptostegia grandiflora fibers(CGFs)were chemically treated using NaOH and silane. Various properties like crystal structure, chemical composition, surface morphology, and thermal degradation were studied using x-ray diffraction (XRD, Fourier transform infrared spectroscopy (FTIR) Scanning electron Microscopy (SEM) and Thermogravimetric analysis (TGA). The increasing cellulose content and the removal of hemicellulose after the chemical treatment indicate the potential for this CGfiber as a better reinforcement element in polymers. The increasing trend of tensile strength was observed for the CGfiber in the following order: silane > NaOH > untreated conditions. Two-stage thermal degradation was observed in all the cases where the maximum thermal degradation was found at the silane-treated CGfibers. Based on their performance, the chemically treated CGfibres can be made into composites and used for structural applications.Peer reviewe

    Experimental investigation and statistical analysis of additively manufactured onyx-carbon fiber reinforced composites

    Get PDF
    This is the peer reviewed version of the following article published in final form at https://doi.org/10.1002/app.50338. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.Availability of additive manufacturing (AM) has influenced the scientific community to improve on production and versatility of the components created with several associated technologies. Adding multiple substances through superimposing levels is considered as a part of three-dimensional (3D) printing innovations to produce required products. These technologies are experiencing an increase in development nowadays. It requires frequently adding substance and has capacity to fabricate extremely complex geometrical shapes. However, the fundamental issues with this advancement include alteration of capacity to create special products with usefulness and properties at an economically viable price. In this study, significant procedural parameters: layer designs/ patterns (hexagonal, rectangular and triangular) and infill densities (30, 40 and 50%) were considered to investigate into their effects on mechanical behaviors of fused deposition modeling (FDM) or 3D-printed onyx-carbon fiber reinforced composite specimens, using a high-end 3D printing machine. Mechanical (tensile and impact) properties of the printed specimens were conclusively analyzed. From the results obtained, it was observed that better qualities were achieved with an increased infill density, and rectangular-shaped design exhibited an optimum or maximum tensile strength and energy absorption rate, when compared with other counterparts. The measurable relapse conditions were viably evolved to anticipate the real mechanical qualities with an accuracy of 96.4%. In comparison with other patterns, this was more closely predicted in the rectangular design, using regression models. The modeled linear regression helps to define the association of two dependent variables linked with properties of the dissimilar composite material natures. The models can further predict response of the quantities before and also guide practical applications.Peer reviewedFinal Accepted Versio

    Cellulosic fiber based hybrid composites: A comparative investigation into their structurally influencing mechanical properties

    Get PDF
    This paper focuses on hybrid and twisted hybrid Indian mallow/roselle cellulosic fiber yarn mat reinforced polyester composites and effects of their wood sawdust filler. The composite materials were fabricated using compression molding technique. There were four different combinations of hybrid yarn mat composite samples used, while the twisted hybrids were six. An evaluation of the hybrid and twisted hybrid mechanical properties for the single and double layer cases of the yarn mat was done with and without wood sawdust filler effects. The samples were tested at both warp and weft directions. From the results obtained at warp direction, it was observed that for the hybrid double layer case, longitudinal yarn mat with wood sawdust (filler) composite sample exhibited better tensile, impact and flexural strength properties in comparison with other related composites of hybrid type reported in literature. Moreover, the modified twisted hybrid double layer composites with longitudinal yarn mat and wood sawdust filler sample recorded significantly greater improvement on the mechanical properties at warp direction, when compared with the hybrid double layer longitudinal yarn mat composites with wood sawdust filler and other reported similar hybrid composite materials. Scanning electron microscopy (SEM) technique was utilized to evaluate morphological internal damage (cracks) and fractured surfaces of the various tested composite samples. Based on their mechanical performances and for further practical evidence, these two types of eco-composites were used to effectively fabricate tri-wheeler auto-wheel hubs and ceiling fan blades, as applicable to automobile and electronics industries, respectively.Peer reviewedFinal Accepted Versio

    Crystal stabilization of α-FAPbI3perovskite by rapid annealing method in industrial scale

    Full text link
    Organic-inorganic hybrid formamidinium lead iodide (FAPbI3) perovskite has shown tremendous attention in recently developed photovoltaics and optelectronic devices. However, it suffers from structural instability complications, particularly the spontaneous phase transition from a dark color photoactive perovskite phase (α-FAPbI3) to a yellow color photo-inactive phase (δ-FAPbI3) at room temperature. To stabilize the photoactive α-FAPbI3, several methods were employed, including compositional engineering, 2D layer deposition on the surface, and solvent engineering method. In this communication, we have proposed a facile sequential rapid annealing method to produce the photoactive α-FAPbI3 perovskite on an industrial scale, which is highly stable at room temperature. The structural, morphological, compositional, and optical properties of the perovskite were studied using X-ray diffraction (XRD), UV-visible absorption, Laser Raman, thermogravimetric analysis (TGA), and field emission electron microscopy with elemental analysis (FE-SEM & EDAX). The strong characteristic diffraction peaks of cubic structure in XRD showed the proposed additives free preparation method is more adaptable for the preparation of high quality α-FAPbI3 perovskite for optoelectronic applications. © 2021 The Author(s).Dr. G. Murugadoss acknowledges to the management of Sathyabama Institute of Science and Technology, Chennai, Tamilnadu, India for provided lab facility. We extend their appreciation to the Deputyship for Research & Innovation, “Ministry of Education” in Saudi Arabia for funding this research work through the project no. ( IFKSURG-1440-014 )

    The synthesis of desired functional groups on PEI microgel particles for biomedical and environmental applications

    No full text
    Polyethyleneimine (PEI) microgels were synthesized by micro emulsion polymerization technique and converted to positively charged forms by chemical treatments with various modifying agents with different functional groups, such as 2-bromoethanol (-OH), 4-bromobutyronitrile (-CN), 2-bromoethylamine hydrobromide (-NH 2 ), and glycidol (-OH). The functionalization of PEI microgels was confirmed by FT-IR, TGA and zeta potential measurements. Furthermore, a second modification of the modified PEI microgels was induced on 4-bromo butyronitrile-modified PEI microgels (PEI-CN) by amidoximation, to generate new functional groups on the modified PEI microgels. The PEI and modified PEI microgels were also tested for their antimicrobial effects against various bacteria such as Bacillus subtilis ATCC 6633, Escherichia coli ATCC 8739 and Staphylococcus aureus ATCC 25323. Moreover, the PEI-based particles were used for removal of organic dyes such as methyl orange (MO) and congo red (CR). The absorption capacity of PEI-based microgels increased with modification from 101.8 mg/g to 218.8 mg/g with 2-bromoethylamine, 216.2 m/g with 1-bromoethanol, and 224.5 mg/g with 4-bromobutyronitrile for MO. The increase in absorption for CR dyes was from 347.3 mg/g to 390.4 mg/g with 1-bromoethanol, 399.6 mg/g with glycidol, and 349.9 mg/g with 4-bromobutyronitrile. © 2015 Elsevier B.V. All rights reserved.King Saud UniversityThis project was supported by King Saud University , Deanship of Scientific Research, Research Chair. -

    Macroporous cryogel metal nanoparticle composites for H 2 generation from NaBH 4 hydrolysis in seawater

    No full text
    Poly(2-hydroxy ethyl methacrylate) p(HEMA), poly(acrylic acid) p(AAc), poly(3-sulfopropyl methacrylate) p(SPM), and poly(4-vinylpyridine) p(4-VP) cryogels from various monomers containing functional groups such as -COOH, -SO 3 H, and -OH, and N monomer were synthesized under cryogenic conditions via free radical polymerization technique. The synthesized cryogels were used as templates for metal nanoparticle synthesis using Co and Ni, and the prepared composite cryogels were utilized in hydrogen (H 2 ) generation from the hydrolysis reaction of NaBH 4 . It was found that the hydrolysis reaction of NaBH 4 in seawater is much faster than in DI water when using the p(SPM)-Co catalyst system. Parameters such as water and metal types for different cryogels, concentration of NaBH 4 , amount of metal catalyst, and temperature were investigated. The hydrogen generation rate (HGR) and turnover frequency (TOF) values were also investigated for temperature dependency. It was found that as the temperature increased from 30 to 70 °C, the HGR and TOF increased from 1288.0 ± 61.2 (ml H 2 ) (g of metal min) -1 and 3.1 ± 0.1 mol H 2 (mol metal min) -1 to 7707.8 ± 179.4 (ml H 2 ) (g of metal min) -1 , and 16.1 ± 0.4 mol H 2 (mol metal min) -1 , respectively. The activation energy, enthalpy, and entropy were 31.1 kJ (mol K) -1 , 27.7 kJ (mol K) -1 , and -196.4 J (mol K) -1 , respectively, for NaBH 4 hydrolysis catalyzed in seawater by p(SPM)-Co composite system. © 2015 Elsevier B.V. All rights reserved.College of Dentistry, King Saud University National Council for Scientific Research: 113T042This project is supported by Surfactant Research Chair, Chemistry Department, College of Science, King Saud University . In addition, the support from the Scientific and Technological Research Council of Turkey ( 113T042 ) is greatly appreciated. -
    corecore