Faculty Publications
Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736
Publications by NITK Faculty
Browse
3 results
Search Results
Item Investigation on mechanical behaviour of filament wound glass/epoxy composites subjected to water absorption and also tribological studies using Taguchi method(Elsevier Ltd, 2020) Biradar, S.; Joladarashi, S.; Kulkarni, S.M.The current study is mainly focused on the mechanical and tribological behaviour of GEC (Glass Epoxy Composites) (GEC- fabricated using filament winding technique) over the effect of various water immersion examinations for a defined time limit. In this study we mainly focus on filament wound glass/epoxy composite samples directly taken from composite pressure vessel. The important aspect of this study is to understand and investigate the percentage reduction or increase in the various mechanical and tribological properties under the influence of moisture. Here three (sea water, purified/distil water, boiling water) water containers where samples are treated as per water absorption test ASTM standard. These treated samples are examined for different mechanical strengths. From impact testing, the influence of boiling water on impact strength of glass/epoxy is high (impact strength in increasing order untreated < distilled < sea < boiling) when compared with other cases. Similar outcomes have been observed in case bending test also. Presence of water molecules enhances mechanical strength as water particles fills the gap or delays the voids or imperfections of samples to reach the boundaries. GEC samples made of filament winding process are examined for wet slurry erosion wear in an erosion testing machine as per the respective ASTM standard. The selection of number of experiments and identifying the most influencing parameter is done using the DOE (Design of Experiments) tool Taguchi L9 method. In the outcomes, erosion rate of glass/epoxy composite have highest influence of large sized sand particles with sand concentration 900 g, at a spindle speed of 1000 rpm. Whereas the smaller sand particles with lesser sand concentration have least impact on the erosion rate. © 2019 Elsevier Ltd. All rights reserved.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 The influence of hygrothermal aging on the hoop tensile strength of glass fiber wound polymer composites fabricated via filament winding technique(Institute of Physics, 2024) Biradar, S.; Hiremath, S.; Vishwanatha, H.M.; Joladarashi, S.; Kulkarni, S.M.The study investigates the impact of moisture environment treatment, on the hoop tensile strength (HTS) of glass fiber-reinforced polymer (GFRP) composites, through hygrothermal aging. GFRP cylinders were fabricated with varied parameters—volume fraction, winding angle, and stacking sequences using a filament winding machine. The fabricated samples are subjected to hygrothermal aging using seawater and tap water with oil at 80 °C for 1080 h (45 days). The HTS tests were performed on unaged and aged samples. There was a reduction in HTS for aged samples which is attributed to heat, seawater contamination, and oil. The highest and lowest HTS values recorded are 402.9 MPa and 118.3 MPa for unaged and tap water with oil-aged samples respectively. HTS in aged samples is compared with unaged samples. The study opens up avenues in identifying the best-suitable combination for retaining HTS under various aging conditions. © 2024 The Author(s). Published by IOP Publishing Ltd.