Effect of Fiber Orientation and Loading on the Tensile Properties of Hardwickia Binata Fiber Reinforced Epoxy Composites

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1 Volume 117 No , ISSN: (printed version); ISSN: (on-line version) url: doi: /ijpam.v117i10.11 ijpam.eu Effect of Fiber Orientation and Loading on the Tensile Properties of Hardwickia Binata Fiber Reinforced Epoxy Composites K. Sudha Madhuri *1, Dr.H.Raghavender Rao 2, Dr.B.ChandraMohan Reddy 3 1 Research Scholar of JNTUA, Ananthapuramu 2 Department of Mechanical Engineering, G.P.R.C.E, Kurnool 3 Department of Mechanical Engineering, J.N.T.U, Anantapuramu * 1 ksmadhurime@gmail.com Abstract In the present research work a new fiber is introduced to find environmental friendly green composites, the effect of fiber orientation and fiber loading on the mechanical properties of Hardwickia Binata fiber reinforced epoxy composites is presented. Hardwickia Binata fiber is used as reinforcement which treated with NaOH solution for enhancing the bonding strength between fiber and resin by removing moisture contents. Samples at different orientations (0 0, 30 0, 60 0, 90 0 ) and varying fiber content (0%, 5%, 10%, 15% and 20%) were prepared by hand lay-up molding process and investigated tensile properties. The results of this study indicate at the 20% fiber loading and 0 0 orientation shows superior tensile properties compared to the other orientations and fiber loading. SEM analysis was carried out to observe the internal structure of the composites, delaminating of fibers, fiber pullouts using ZEISS scanning electron microscope. Keywords Composites, Epoxy, Hardwickia Binata fiber, SEM, Tensile strength 1. Introduction Since the past few decades natural fibers are being used as an alternative reinforcement for industrial fibers in many applications like structural, aerospace, sports, packaging and automotive industries[1]. Though there are some disadvantages of natural fiber reinforced polymer composites like moisture absorption, compatibility between fiber and resin which affects the strength of the polymer composites[3].this can be improved by chemical treatments(removing dirt and other particles present in the fiber),manufacturing process, reinforcement etc. Apart from these there are factors like fiber orientation, fiber content, polymers, fillers etc. Fiber orientation and fiber loading mainly influences the tensile properties in any natural fiber reinforced polymer composites. Tensile properties of the polymer composites are increased by adding fiber since fiber has good strength and stiffness compared to the polymer itself. Unidirectional fiber has much strength compared to short fiber reinforced natural composites [4]. Ramesh et.al found the tensile properties of sisal, jute and glass fiber reinforced hybrid composites in 0 0 and 45 0 orientations and concluded that fiber orientation and fiber loading plays an important role in tensile strength analysis [7]. Li et al studied that by increasing the flax fiber resulted in increasing tensile properties [8]. Ma X et.al studied the tensile properties of micro winceyette fiber with the increase fiber content, the tensile strength was approximately tripled to 150MPa [9]. Venkateshwaran et.al found the tensile properties of banana reinforced epoxy composites varying fiber length and content and found that at 15mm fiber length and 16% fiber loading gives maximum strength [10]. Shanmugam et.al treated palmyra leaf stalk fibers and jute fibers and used as reinforcement in polyester matrix composites to improve the tensile properties [11]. Palanikumar et.al studied tensile properties of sisal and glass hybrid composites in longitudinal and transverse directions and concluded that tensile strength in longitudinal is high compared to transverse direction [12]. Silva et al. found the effects of silica micro particles on the tensile properties of banana fibers reinforced epoxy composites and evaluated, significant increase in tensile strength were found [13]. In the present work Tensile properties were investigated varying fiber orientation and loading and evaluated that the maximum strength of the fiber is at 0 0 fiber orientation and at 20% fiber loading and suggested that Hardwickia Binata fiber as an eco-friendly green composite and used as an alternative for synthetic fibers. 2. Materials and Methods A. Materials In the current research work, Hardwickia Binata fibers are used as the reinforcement. Matrix, Araldite LY-556 and hardener HY-951, polyvinyl alcohol (PVA) is used as mould releasing agent, glass moulds for fabrication. Physical properties of Hardwickia Binata fiber were mentioned below in Table: 1 Table: 1 Physical Properties of Hardwickia Binata Fiber 1 57

2 B. Extraction of Fibers In the present research the newly identified Hardwickia Binata Fiber obtained from the bark of trees, hard stems of tree were soaked in water for days and fiber extracted through retting process. The common name of Hardwickia Binata Plant is Anjan or Narepa which belongs to the family caesalpiniaceae native to tropical and subtropical regions are collected near forest area of Thambarajapalli, Kurnool district, A.P, India. C. Chemical Treatment Fibers extracted are washed with normal water and finally soaked in 5% NaOH solution for 1hr and washed with distilled water to remove the sticky materials, dirt and other contents in the fiber which affects the mechanical strength. Figure: 1 Processed Hardwickia Binata Fiber D. Preparation of Composites To prepare the composites unidirectional fiber of different fiber loadings (5%, 10%, 15% and 20%) and orientations (0 0, 30 0, 60 0 and 90 0 ) are supposed to prepare. Glass moulds of 150x150x3 mm are cleansed and dried to remove any dirt and moisture present. E. Curing The moulds thus prepared were put under compression for 24 hrs in normal atmospheric temperature. Later composite plates were removed from the moulds and kept in the oven for post curing at C for 2 hrs. Specimens of required dimensions i.e 150x15x3mm are made from the composite plates F. Tensile Test Samples as per ASTM D were subjected to tensile strength and modulus was determined using INSTRON 3369 universal testing machine. The specimen dimensions are taken as 150x15x3 mm and gauge length was maintained at 100mm with the cross head speed at 5mm/min. 3 Figure:3 Specimens at different Orientations after tensile test F. Scanning Electron Microscope Analysis Interfacial bonding of the matrix and the reinforcement, fracture behavior, and fiber pull-out of samples after tensile tests are observed using ZEISS scanning electron microscope. The fractured portions of the samples were cut by 10x10x3 mm and gold coated on the surface uniformly for Analysis. The accelerating voltage used in this work is 10 kv. 3. Results Specimens of Hardwickia Binata fiber reinforced Epoxy composites were subjected to tensile test and the results were observed in two different categories. The Tensile strength varying fiber loading and keeping orientation as constant, maximum tensile strength of 99.91mpa has been observed at 0 0 fiber orientation and minimum tensile strength of 42.73mpa is observed at 90 0 fiber orientation.again varying fiber orientation and keeping percentage weight of fiber loading constant, maximum tensile strength is observed at 20% fiber loading and minimum at 5% fiber loading. The results of tensile strength were shown graphically below. It can be known that from fiber orientation, tensile strength will be maximum along the direction of loading. Also from fiber loading, tensile strength also depends on the weight of the fiber. TABLE:2 Results of Tensile Strength of Hardwickia Binata Fiber Reinforced composites Figure: 2 UTM Testing machine with tensile specimen 2 58

3 (perpendicular to the direction of loading). These are of longitudinal and a transverse direction of fiber loading. Strength of the composite also depends on the composition of epoxy, fiber flexibility and mainly reinforcement of fiber and matrix in the composite. From the morphology analysis, Micrographs of the samples subjected to the tensile loading flow of resin, fractured fiber and gap due to fiber pullouts formed are clearly visible and concluded that there is good bonding between fiber and matrix. This study provided evidence for the natural fiber composites by a proper fabrication of Hardwickia Binata fiber reinforced epoxy composites in order to find a suitable cost-performance balance, environmentally friendly material. 5. Acknowledgement The author expresses sincere thanks to Dr. V.Chandrasekhar, Department of Mechanical Engineering, RGMCET, Nandyal for his endless support. 6. References Scanning Electron Microscope Analysis: The Interfacial bonding of the composites is studied through ZEISS scanning electron microscope. Micrographs of the samples subjected to the tensile loading are shown in the following figures, flow of resin, fractured fiber and gap due to fiber pullouts formed are clearly visible. Figure:6 (a) SEM Micrograph of the fractured specimen after tensile testing with void formation Figure: 6 (b) SEM Micrograph of the fractured specimens after tensile testing with fiber pullouts 4. CONCLUSIONS The mechanical property i.e. Tensile strength is experimentally conducted on Hardwickia Binata fiber reinforced epoxy composites. From the results and graphs it can be concluded that both fiber orientation and fiber loading is important in deriving the strength of the Hardwickia Binata fiber reinforced epoxy composites. Maximum tensile strength is observed as mpa at 0 0 fibers as it is in the direction of loading and minimum of mpa at 90 0 fiber orientations [1] Malkapuram R, Kumar V, Yuvraj SN. Recent development in natural fibre reinforced polypropylene composites. J Reinf Plast Compos 2008; 28: [2] Nabi Saheb D, Jog JP. Natural fiber polymer composites: a review. Adv PolymTechnol 1999; 18: [3] Wambua P, Ivens J, Verpoest I. Natural fibres: can they replace glass in fibre reinforced plastics. Compos Sci Technol 2003; 63: [4] Ahmad I, Baharum A, Abdullah I. Effect of extrusion rate and fiber loading on mechanical properties of Twaron fiber-thermoplastic natural rubber (TPNR) composites. J Reinf Plast Compos 2006; 25: [5] Holbery J, Houston D. Natural-fiber-reinforced polymer composites in automotive applications. JOM 2006;58(11):80 6. [6] Hajnalka H, Racz I, Anandjiwala RD. Development of HEMP fibre reinforced polypropylene composites. J Thermoplast Compos Mater 2008; 21: [7] Ramesh, M., K. Palanikumar, and K. H. Reddy. 2013b. Mechanical property evaluation of sisal-jute-glass fiber reinforced polyester composites. Composites Part B: Engineering 48: 1 9. doi: /j.compositesb [8] fiber content on properties of injection molded flax fiber- HDPE biocomposites. Can Biosyst Eng 2009;08 148:1 10. [9] Ma X, Yu J, Kennedy JF. Studies on the propertied of natural fibres-reinforced thermoplastic starch composites. Carbohydr Polym 2005;62: [10] N. Venkateshwaran a A. ElayaPerumal a, A. Alavudeen b, c M. Thiruchitrambalam Mechanical and water absorption behaviour of banana/sisal reinforced hybrid composites International journal of materials and design 32 (2011) [11] Shanmugam, D., and M. Thiruchitrambalam Static and dynamic mechanical properties of alkali treated unidirectional continuous palmyra palm leaf stalk 3 59

4 fiber/jute fiber reinforced hybrid polyester composites.materials&design50: doi: /j.matdes [12] K. Palanikumar, M. Ramesh & K. Hemachandra Reddy (2016) Experimental Investigation on the Mechanical Properties of Green Hybrid Sisal and Glass Fiber Reinforced Polymer Composites, Journal of Natural Fibers,13:3, ,DOI: /

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