Anand M. Raikar,
Pooja N,
Nandkishore D. Rao,
Srikanth H. V.,
Karthikeyan R,
Bharath Kumar S,
- Assistant Professor, Department of Aerospace Engineering, Ramaiah Institute of Technology, Bangalore, Karnataka, India
- Research Associate, Department of Chemistry, Nitte Meenakshi Institute of Technology, Nitte (Deemed to be University), Bangalore, Karnataka, India
- Professor, Department of Mechanical Engineering, P. K. Technical Campus, Chakan, Pune, Maharashtra, India
- Professor, Department of Aeronautical Engineering, Nitte Meenakshi Institute of Technology, Nitte (Deemed to be University), Bangalore, Karnataka, India
- Associate Professor, Department of Aeronautical Engineering, Er. Perumal Manimekalai College of Engineering, Hosur, Tamil Nadu, India
- Research Coordinator, Department of Aeronautical Engineering, Nitte Meenakshi Institute of Technology, Nitte (Deemed to be University), Bangalore, Karnataka, India
Abstract
This study investigates the mechanical performance of epoxy composites reinforced with hemp, ramie, and flax fibers and evaluates the effect of fiber hybridization. Single-fiber composites were fabricated using hand lay-up followed by vacuum-bagging consolidation and compared with three hybrid systems: hemp–flax (HF), hemp–ramie (HR), and flax–ramie (FR). Tensile, flexural, and drop-weight impact properties were evaluated using standardized test procedures. Among the single-fiber composites, flax exhibited the highest tensile strength of 88.26 ± 0.28 MPa and flexural strength of 114.97 ± 3.31 MPa, followed by ramie and hemp. Hybridization produced combination-dependent responses. The flax–ramie hybrid achieved the highest tensile strength of 92.32 ± 1.53 MPa, while the hemp–ramie hybrid showed a 69.6% improvement in tensile strength compared with hemp alone. In contrast, the flexural strength of the hybrid systems remained below that of flax, demonstrating that hybridization does not universally improve every mechanical property. SEM fractography revealed fiber pull-out, fiber–matrix debonding, matrix cracking, fiber fracture, fibrillation, crack deflection, localized voids, and resin-rich regions. These observations indicate multiple interacting failure mechanisms and support the role of fiber architecture and interfacial behavior in determining composite performance. Overall, hybridization provides a means of tailoring the balance between tensile, flexural, and impact performance. The developed natural-fiber/epoxy composites show potential for selected structural and semi-structural applications where mechanical performance, low density, and sustainability are required.
Keywords: Natural fiber composites, hybrid composites, flax fiber, hemp fiber, ramie fiber, epoxy, mechanical properties, sustainable material
[This article belongs to Special Issue under section in Journal of Polymer & Composites (jopc)]
References
1. Pickering KL, Efendy MGA, Le TM. A review of recent developments in natural fibre composites and their mechanical performance. Compos Part A Appl Sci Manuf. 2016;83:98–112. doi: 10.1016/j.compositesa.2015.08.038.
2. Faruk O, Bledzki AK, Fink HP, Sain M. Biocomposites reinforced with natural fibers: 2000–2010. Prog Polym Sci. 2012;37(11):1552–1596. doi: 10.1016/j.progpolymsci.2012.04.003.
3. Thakur VK, Thakur MK, Gupta RK. Raw natural fiber-based polymer composites: a review. Carbohydr Polym. 2014;109:102–117. doi: 10.1016/j.carbpol.2014.04.009.
4. Dhakal HN, Zhang ZY, Richardson MOW. Effect of water absorption on the mechanical properties of hemp fibre reinforced polyester composites. Compos Sci Technol. 2007;67(7–8):1674–1683.
5. Nurazzi NM, Asyraf MRM, Fatimah Athiyah S, Shazleen SS, Rafiqah SA, Harussani MM, et al. A review on mechanical performance of hybrid natural fiber polymer composites for structural applications. Polymers (Basel). 2021;13(13):2170.
6. Prem Kumar R, Muthukrishnan M, Felix Sahayaraj A. Effect of hybridization on natural fiber reinforced polymer composite materials: A review. Polym Compos. 2023;44(8):4459–4479.
7. Kumlu U, Karaçor B, Özcanlı M. Effects of different production methods and hybridization on mechanical characteristics of basalt, flax, and jute fiber-reinforced composites. Mater Test. 2025;67(1):111–124.
8. Thimmegowda DY, Hindi J, Markunti GB, Kakunje M. Enhancement of mechanical properties of natural fiber reinforced polymer composites using different approaches: A review. J Compos Sci. 2025;9(5):220. doi: 10.3390/jcs9050220.
9. Pingulkar H, Mache A, Munde Y, Siva I. A comprehensive review on drop weight impact characteristics of bast natural fiber reinforced polymer composites. Mater Today Proc. 2021;44:3872–3880. doi: 10.1016/j.matpr.2020.12.925.
10. Francucci G, Palmer S, Hall W. External compaction pressure over vacuum-bagged composite parts: Effect on the quality of flax fiber/epoxy laminates. J Compos Mater. 2018;52(1):3–15. doi: 10.1177/0021998317701998.
11. ASTM International. ASTM D3039/D3039M: Standard test method for tensile properties of polymer matrix composite materials. West Conshohocken (PA): ASTM International.
12. ASTM International. ASTM D790: Standard test methods for flexural properties of unreinforced and reinforced plastics and electrical insulating materials. West Conshohocken (PA): ASTM International.
13. ASTM International. ASTM D7136/D7136M-15: Standard test method for measuring the damage resistance of a fiber-reinforced polymer matrix composite to a drop-weight impact event. West Conshohocken (PA): ASTM International.
14. Sumesh KR, Ajithram A, Palanisamy S, Kavimani V. Mechanical properties of ramie/flax hybrid natural fiber composites under different conditions. Biomass Convers Biorefin. 2023;14:29579–29590. doi: 10.1007/s13399-023-04628-5.
15. Mohanavel V, Diwakar G, Govindasamy M, Singh V, Rajakumar IPT, Soudagar MEM, et al. Fabrication of ramie/hemp fibers-reinforced hybrid polymer composite: A comprehensive study on biological and structural application. AIP Adv. 2024;14(8):085325. doi: 10.1063/5.0223604.
16. Seid AM, Adimass SA. Review on the impact behavior of natural fiber epoxy based composites. Heliyon. 2024;10(20):e39116. doi: 10.1016/j.heliyon.2024.e39116.
17. Le Duigou A, Kervoelen A, Le Grand A, Nardin M, Baley C. Interfacial properties of flax fibre-epoxy resin systems: Existence of a complex interphase. Compos Sci Technol. 2014;100:152–157. doi: 10.1016/j.compscitech.2014.06.009.
18. Fegade R, Chaudhari R, Nehete R, Tale V, Mate D, Chopade P, et al. Comprehensive review of composite materials: Classification, manufacturing methods, mechanical behavior, failure modes, and emerging applications. J Polym Compos. 2026;14(1):923–939.
19. Fegade R, Chaudhari R, Nehete R, Tale V, Mate D, Yadav S, et al. Development and mechanical characterization of hybrid natural fiber-reinforced polymer matrix composites for structural applications. J Polym Compos. 2026;14(1):1181–1189.
20. Yadav S, Pawar RS, Tale V, Sambare A, Fegade R, Kolgiri S. Evaluating fiber volume fraction and defects in fiber reinforced polymer composites for T-joint applications. J Polym Compos. 2026;14(1):1222–1235.
21. Wadate PR, Fegade RS, Gaikwad MN, Sawalkar YM, Shevale RA. Design and mathematical quantification of a compressed-air vehicle. J Polym Compos. 2026;14(1):1026–1035.
22. Tike RH, Gautam NK, Kattimani PC, Bhople N, Fegade R, Nehete R, et al. Design and computational analysis of hybrid carbon fiber-enhanced metal matrix composite spur gears. J Polym Compos. 2026;14(1):158–172.
23. Tike RH, Gautam NK, Yadav TK, Deokar S, Fegade R, Nehete R, et al. A systematic review of advanced composite materials for high-performance spur gear applications. J Polym Compos. 2026;14(1):209–220.
Journal of Polymer & Composites
| Volume | 14 | |
| Special Issue | 04 | |
| Received | 27/07/2026 | |
| Accepted | 18/08/2026 | |
| Published | 21/08/2026 | |
| Publication Time | 25 Days |