38 research outputs found
Effects of sand and gating architecture on the performance of foot valve lever casting components used in pump industries
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
© 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
Animal fiber characterization and fiber loading effect on mechanical behaviors of sheep wool fiber reinforced polyester composites
© 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
© 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
Cellulosic fiber based hybrid composites: A comparative investigation into their structurally influencing mechanical properties
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
Experimental investigation and statistical analysis of additively manufactured onyx-carbon fiber reinforced composites
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
Tuning visible emission of core-shell nanostructure by exchange the inner and outer layer
Herein, we report that synthesis of ZnS/Bi2S3 and Bi2S3/ZnS core-shell nanostructure prepared by ‘one-pot’ chemical method. We have studied the effect of structural, morphological, optical and thermal properties by exchanging the inner and outer layer of core-shell nanoparticles. The samples were studied using various characterization techniques such as XRD, TEM, FTIR, UV–Vis, Photoluminescence and TG-DTA. The XRD and TEM results demonstrated that the synthesized core-shell nanoparticles were in cubic (ZnS)-orthorhombic (Bi2S3) mixed crystal structures with a diameter of 18.6 nm and 16.3 nm with extremely monodispersing. The obtained result provides a new and simple route for synthesis of sulfide-based core-shell nanoparticles with high crystal quality. © 2021, S.C. Virtual Company of Phisics S.R.L. All rights reserved.Sathyabama Institute of Science and Technology, ChennaiKing Saud University, KSUThe authors acknowledge the Researchers Supporting Project Number (RSP-2021/354) King Saud University, for financial supports, Riyadh, Saudi Arabia. The author Dr. G. Murugadoss thanks the Chancellor, President, and Vice Chancellor, Sathyabama Institute of Science and Technology, Chennai for the support and encouragement
Mechanical, physical and thermal properties of polylactic acid filament composite reinforced with newly isolated Cryptostegia grandiflora fiber
© 2024 The Author(s). Published in BioResources. This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC), https://creativecommons.org/licenses/by-nc/4.0/By leveraging the properties of natural or plant fibers and possibilities through three-dimensional (3D) printing technology, a composite filament was fabricated by incorporating newly isolated Cryptostegia grandiflora fiber (CGF), as a reinforcement with polylactic acid (PLA) by using a twin-screw extruder. The fabricated composite filament and pure PLA filament were 3D-printed, using fused deposition modeling (FDM). This study investigated the mechanical, physical, and thermal properties of the 3D-printed CGF reinforced composite filament samples. The mechanical properties of the samples fabricated with 10 wt% CGF were better than that of samples with pure PLA. In addition, impact, tensile, flexural strengths and hardness were increased by 35.6, 33.6, 14.1, and 1.7%, respectively, when compared with the sample with pure PLA. The fractured surface morphology of tensile samples showed a uniform distribution of CGF within the PLA. The addition of CGF improved the thermal stability of the 3D-printed CGF/PLA composite sample by 15%. Therefore, the printed structure could serve as an alternative material for various uses, considering contemporary concepts of sustainability, availability, environmental friendliness, and cost effectiveness.Peer reviewe
Novel Superhydrophobic Sand and Polyurethane Sponge Coated with Silica/Modified Asphaltene Nanoparticles for Rapid Oil Spill Cleanup
Superhydrophobic nanomaterials are promising in the important pursuit to alleviate the environmental pollution caused by the petroleum crude oil industry, especially to clean-up oil spills. In this work, asphaltenes isolated from crude oil were modified to act as capping agents during the synthesis of hydrophobic silica nanoparticles (HSNPs). The chemical structure, surface morphology, particle size, and surfaces charge of HSNPs were investigated. The contact angles of water droplets on HSNP film surfaces were measured to investigate their wetting properties. Finally, superhydrophobic sand and polyurethane sponge were prepared by coating them with HSNPs and applied in the cleanup of oil spills of viscous heavy Arabian crude oil