Faculty Publications
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Item Fracture toughness of flax braided yarn woven PLA composites(Bellwether Publishing, Ltd., 2021) Kanakannavar, S.; Jeyaraj, J.Flax fiber braided yarn plain woven fabric reinforced Poly Lactic Acid (PLA) bio-composites are fabricated using film stacking and hot-press compression molding method. Effect of fiber weight fraction on tensile and fracture properties of the bio-composites is studied and fractured surfaces are analyzed using scanning electron microscope (SEM) images. It is found that tensile modulus and strength increases by 62.11 and 59.75% respectively for 35 wt.% of the braided fabric reinforcement compared to pristine PLA. Fracture toughness study is performed on single-edge-notched-bend (SENB) specimens using three point bending method. It is found that plane-strain fracture toughness (KIC) and strain energy release rate (GIC) values of the PLA composites are 71.61 and 124% higher than pure PLA for 35 wt.% braided fabric reinforcement. KIC values of the braided fabric reinforced PLA composites are much high compared to similar natural fiber composites reported in literature. This is attributed to high resistance offered by the interweaving yarns of the braided fabric hence more energy is required to begin crack propagation compared to other typical forms of reinforcement. © 2021 Taylor & Francis Group, LLC.Item Thermal buckling of braided flax woven polylactic acid composites(SAGE Publications Ltd, 2021) Kanakannavar, S.; Jeyaraj, J.This study presents influence of thermal environment on buckling behaviour of natural fibre braided yarn fabric reinforced polylactic acid composite beams. The thermal buckling study is carried out using an in-house built experimental set up for beam like composites exposed to different types of in-plane temperature variations. Influences of temperature variations, direction of loading and volume fraction of fibre are studied in detail. Results indicate that deflection behaviour of natural fibre braided fabric/polylactic acid beam is entirely different from the polylactic acid beam. Enhancement of natural fibre braided fabric reinforcement on thermal deflection is observed only at higher temperature as less deflection is observed for polylactic acid beams at lower temperature range (25°C to 45°C). According to the nature of heating, maximum deflection in the range of 0.503 cm to 1.082 cm corresponding to the temperature range of 63.443°C to 67.917°C is observed for polylactic acid beams. For natural fibre braided fabric/polylactic acid beams, the maximum deflection range is 0.826 cm to 0.105 cm corresponding to the temperature range of 57.031°C to 44.742°C according to the heating condition. Thermal deflection of natural fibre braided fabric beam is sensitive to testing orientation of the beam and maximum deflection for warp loading is 29% to 54% lower than the weft loading. © The Author(s) 2020.Item Tribological behaviour of natural fibre 3D braided woven fabric reinforced PLA composites(SAGE Publications Ltd, 2021) Kanakannavar, S.; Jeyaraj, J.; Ramesh, M.R.This study aims to investigate the potential of natural fibre 3D braided woven fabric (NFBF) reinforced PLA (poly lactic acid) composites for tribological applications. Composites with different fibre contents are prepared using film stacking process and hot press methods. Friction co-efficient and wear rate of the composites are analysed using pin-on-disc tribometer under dry contact sliding condition and various operating conditions (velocity and load) for a fixed sliding distance of 3000 m. The morphology of the worn surfaces is studied using scanning electron microscope (SEM). The reinforcement of fibre with the PLA reduced the polymer film generation and improved the surface roughness significantly. Wear rate of the composites are decreased drastically compared to pure PLA. Composite with 35 wt.% of NFBF reinforcement showed better wear characteristics. © IMechE 2020.Item Fabrication and mechanical properties of braided flax fabric polylactic acid bio-composites(Taylor and Francis Ltd., 2022) Kanakannavar, S.; Jeyaraj, J.This paper primarily describes the development of flax braided yarn fabric reinforced thermoplastic composites. Plain woven fabric is made by interlacing 3D braided yarn produced by solid braiding method. Tensile properties of braided yarn and woven fabric are evaluated. Solution casting is used prior to composite fabrication to prepare polylactic acid (PLA) and (natural fiber braided fabric) NFBF–PLA sheets. Followed by this, composite laminates are prepared using through film stacking and compression molding. Influence of number of layers of fabric and loading along warp and weft directions on mechanical properties such as tensile, flexural and impact properties are presented. It is observed that the reinforcement enhances the tensile, flexural and impact properties of the composite significantly for the warp loading. Results also clearly indicates that braided yarn fabric reinforcement have the potential for significant improvement of mechanical and thermal properties of PLA composites. © 2021 The Textile Institute.Item Tensile Behaviour of Double-Edge Notched Flax Braided Yarn Woven Fabric Reinforced PLA Composite(Korean Fiber Society, 2023) Kanakannavar, S.; Pitchaimani, J.; Goh, K.-L.Biodegradable composites were fabricated from poly-lactic acid (PLA) reinforced by flax braided-yarn woven fabric. Composites with different fabric content (corresponding to the 1, 2 and 3 layers of fabric respectively) were obtained by solution casting and compression moulding processes. Tensile fracture properties were evaluated using the double-edge-notch-tension (DENT) test. A scanning electron microscope was used to look at the fractographic features. Reinforcement of braided-yarn fabric resulted in enhanced tensile fracture strength (σf) and toughness of PLA composite. Fracture toughness (KIC) of the composite improved with the fibre contents, namely 64, 79 and 89%, which correspond to 1, 2 and 3 layers of fabric. The improvement in the tensile fracture characteristics of the composites could be contributed by the presence of an effective interfacial bonding of fibre matrix. © 2023, The Author(s), under exclusive licence to the Korean Fiber Society.Item Interlaminar, free vibration, HDT and water absorption properties of braided flax woven fabric PLA biocomposites(Taylor and Francis Ltd., 2024) Kanakannavar, S.; Jeyaraj, J.The presented research investigates the influence of braided flax woven-fabric filled with polylactic acid (PLA) polymer on interlaminar shear strength (ILSS), free vibration, heat deflection temperature (HDT) and water absorption. For this purpose, flax fibre-braided yarn and its fabric are prepared using solid braiding and plain weaving techniques. Then, PLA biocomposites are developed by solution casting and hot-press moulding processes. Shear test results showed, the addition of braided flax fibre increased the ILSS of composites compared to unreinforced PLA. Natural frequencies of the composite beams are improved with the braided flax reinforcement. Composites filled with three fabric layers showed higher frequency due to higher structural strength and stiffness associated with these composites. Bio-composites HDT is enhanced with the addition of braided flax fibre from 61.78% to 132.97%. The results of a water absorption test in distilled and seawater revealed that the composites have a relatively high water uptake in distilled water. © 2023 The Textile Institute.Item Relation between water absorption and mechanical properties of flax 3D braided yarn woven fabric PLA bio-degradable composites(SAGE Publications Inc., 2024) Kanakannavar, S.; Pitchaimani, J.Natural fibre (flax) plain type of woven fabric is developed by using solid braided yarn and is utilised as filler material and PLA (polylactic acid) as a matrix. Solution casting is then used to create sheets of pure PLA and flax fabric–PLA. Composites are manufactured by sheets sequencing technique using the hot compression moulding method. Water absorption, thickness swelling and flexural tests are performed in loading directions of warp and weft of the composites. Results revealed that the absorption of water and swelling of thickness are enriched with an addition of flax fabric. The weft direction loaded composite displayed greater values of water uptake and thickness swelling. The warp direction loaded composites demonstrated the highest flexural strength (92.3 MPa) and modulus (4.5 GPa) compared to weft direction loaded composites. These values are decreased after water absorption. © The Author(s) 2024.Item Mode-I fracture behaviour of aramid/glass-epoxy interply hybrid composites(SAGE Publications Ltd, 2025) Kanakannavar, S.; Biradar, S.; Hiremath, S.; Rajole, S.; Pitchaimani, J.; Kulkarni, S.M.; Goh, K.-L.This article presents the influence of hybridisation of aramid and glass fibre woven fabric on fracture toughness (KIC) of the composites. Experiments using single-edge-notched-bending (SENB) were conducted to investigate the hybridisation effect on the Mode I fracture toughness specimen of aramid/glass laminates. The results revealed that the aramid epoxy composites yielded the highest KIC, followed by aramid/glass epoxy hybrid composites, and finally, glass epoxy composites, which exhibited the lowest KIC. Fracture micrographs of the hybrid composites showed similar fracture patterns – fibre pullout, fibre rupture and matrix rupture – to those of the aramid and glass epoxy composites. The mechanical properties of the hybrid composites being inferior to those of the aramid epoxy composites suggest that there is no advantage in using glass fibres to partially replace aramid fibres in achieving hybrid composites. © The Author(s) 2025