ANALYSIS OF HYBRID FIBER COMPOSITES USING JUTE AND GLASS FIBERS

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1 ANALYSIS OF HYBRID FIBER COMPOSITES USING JUTE AND GLASS FIBERS Sujeeth Mohandas 1, Prasanth Ganesan 2, Vinith Kumar Agoram 3 1,2,3 Department of mechanical engineering,prince Shri Venkateshwara Padmavathy Engineering College Abstract- Fiber reinforced composites are currently being replaced in many areas such as automotives, construction areas etc. because of their strength, light weight and their availability. In this project we are going to analyze the mechanical properties of the hybrid FRP composites. The mechanical properties such as tensile strength, compressive strength, shear strength, flexural strength and impact strength of the jute and glass fiber reinforced polymer composites are to be determined. The main motive of our project is to fabricate a composite which should be considered as the suitable replacement in the automobile industries since we are intended in fabricating a material with higher mechanical properties at a comparatively reduced cost. Keywords-Hybrid fiber composite, Tensile properties, Compressive properties, Shear properties, Impact properties, Flexural properties, Water absorption, Flammability, SEM analysis. I. INTRODUCTION Fiber-reinforced plastic (FRP) composite is a composite material made of a polymer matrix reinforced with fibers. The fibers can be natural or synthetic or can be a combination of both (hybrid) and the polymers used are usually epoxy, vinyl esters, polyesters, polyurethane, polypropylene, etc. These composites are generally classified into Natural fiber based polymer composites. Synthetic fiber based polymer composites. Hybrid fiber reinforced polymer composites Natural fiber based polymer composites Lingo cellulose natural fibers are excellent raw materials for production of wide range of composites for different applications. The interest in using natural fiber such as different plant fiber as reinforcement in polymers increased during last few years. The interest in natural fiber reinforced polymer composite materials is rapidly growing both in terms of industrial applications and fundamental research. They are renewable, cheap, completely or partially recyclable and biodegradable. These fibers are incorporated into a matrix material such as thermosetting plastics, thermoplastics or biopolymers Synthetic fiber based polymer composites Synthetic fibers are fibers made by humans with chemical synthesis, as opposed to natural fibers that humans get from living organisms with little or no chemical changes. In general, synthetic fibers are created by extruding fiber-forming materials through spinnerets into air and water, forming a thread. These fibers are called synthetic or artificial fibers. Some fibers are manufactured from plant-derived cellulose and are thus semi synthetic, whereas others are totally synthetic, being made from crudes and intermediates including petroleum, coal, limestone, air, and water. In the textile industries, cellulose fibers are usually differentiated from synthetic fibers in the sense of fully synthetic ones. DOI: /IJRTER EN5OE 359

2 Synthetic fibers are more durable than most natural fibers and will readily pick-up different dyes. In addition, many synthetic fibers offer consumer-friendly functions such as stretching, waterproofing and stain resistance. Compared to natural fibers, many synthetic fibers are more water resistant and stain resistant. As an added advantage, synthetic fibers do not break down easily when exposed to sunlight, water or oil Hybrid fiber reinforced polymer composites Natural fiber composites are often poorer in properties, mostly mechanical, compared to synthetic fiber composites. A possible solution to this issue is the use of natural fiber/synthetic fiber combination in polymer hybrid composites. Although the bio-degradability of the composites is compromised by synthetic fibers, this is compensated by the improvement in their mechanical and physical properties. Hybrid composites use more than one kind of fibers in the same matrix and the idea is to get the synergistic effect of the properties of both fibers on the overall properties of composites. II. SELECTION OF FIBERS The points to be noted in selecting the reinforcements include compatibility with matrix material, thermal stability, density, melting temperature, etc. The compatibility, density, chemical and thermal stability of the reinforcement with matrix material is important for material fabrication as well as end application. Also, the role of the reinforcements depends upon its type in structural composites. The various factors to be considered in fiber selection are studied through literature survey [1]. In dealing with natural fiber composites, we are more concerned with material selection criteria such as strength, stiffness, low cost, lightweight, availability, renewability, recyclability, biodegradability, and environmental friendliness. Most of these criteria are unique to natural fiber composites and therefore many industries are very serious about adopting these materials for their products. Due to the rapid growth of the accessible set of materials, sophisticated relationships among various evaluative criteria, in addition to selection parameters of materials appear. This has made the synergy between materials characteristics and their desired performance in selecting the most appropriate materials for a particular application a challenging task. Figure 1. Specific strength comparison of natural fibers The above figure shows that the specific strength of flax is greater when compared to that of other natural fibers but, the disadvantage of flax is that it offers bad adhesion and more prone to humidity retention which makes the constraint of using it in external environment. Upon considering the Hemp and Jute fiber, the production of hemp is limited due to presence of cannabis content in it and the production of jute is in large scale. Also the effect of humidity on jute fiber is less All Rights Reserved 360

3 compared with other fibers. Bidirectional jute fibers are chosen after comparison of performance of unidirectional and bidirectional jute fibers [2]. Although jute posses several advantages there are some disadvantages such as low creep resistance, poor drape property, etc. In order to overcome these disadvantages, synthetic fiber can be blended with jute fiber. There are several synthetic fibers available such as glass fiber, carbon fiber, aramid etc. Among these fibers glass fibers are extensively used because of its sufficient mechanical properties and low cost. Hence E-glass fiber is chosen for blending with jute fiber since E-glass possesses better strength, chemical properties and better insulation properties. III. SELECTION OF RESIN Resins are of utmost importance within the composites markets as they bind the fibers together and help create the material s strength and stiffness characteristics. There are two types of resin systems: thermoset and thermoplastic. In a thermoset, the resin molecules are locked together in a irreversible way after a thermal cure; it is a one-way cure that cannot be undone. In a thermoplastic resin the chemical link which is bonding the molecules together can be broken again and again by increasing the temperature steadily which causes the matrix to go from solid to liquid. In the same way, when cooled down the thermoplastic matrix solidifies. Some of the Thermoset resins that are playing a key role in the composite industry are Polyester, Vinyl Ester, Epoxy, Phenolic Resins and Cyanate Ester and Bismaleide. Based on the fact that vinyl ester and its properties are in-between polyester and epoxy, the disadvantages are benefits compared to polyester but drawback compared to epoxy. The most striking disadvantage of polyester resin are the mechanical properties which are not as good as, for example, epoxies. Furthermore, polyester resin has high styrene emission in open mould which is perceived as a disadvantage and that requires special precautions when processing. Phenolic Resin also has disadvantages which are mainly characterized by reasonable to low mechanical properties. The reaction of the phenol and aldehyde creates the danger of free formaldehyde. Hence epoxy resin was found to be suitable. Epoxy resins are low molecular weight pre-polymers or higher molecular weight polymers which normally contain at least two epoxide groups. The epoxide group is also sometimes referred to as a glycidyl or oxirane group. A wide range of epoxy resins are produced industrially. The raw materials for epoxy resin production are today largely petroleum derived, although some plant derived sources are now becoming commercially available. The mechanical properties and its resistance or environmental degradation which makes the resin system especially attractive to the aircraft industry. Furthermore, epoxy is water resistance and therefore used heavily within the marine industry. The adhesive properties and the low shrinkage are further benefits of epoxies. Finally, epoxies cure easily and quickly making them beneficial for numerous projects. Also hardeners play an important role in curing of resin for better binding of resin and fibers. The hardeners used aliphatic amine hardeners as referred [3]. Therefore mpda (meta-phenylenediamine) is used as catalyst. IV. FABRICATION PROCESS The specimens were fabricated by using hand lay-up process and the procedure was as follows: Initially the jute fiber and the glass fibers were cut for the required dimensions and then soaked in 5% NaOH solution for about 1 hour. Then they are removed and washed with distilled water All Rights Reserved 361

4 remove NaOH content in the fiber and then dried for 24 hours. Again the fibers are cut for required dimensions to remove extra fiber. Then a polythene A3 sheet is placed on a plane surface, over which the layers of the fibers has to be placed. Epoxy Resin was then mixed with the mpda(m- Phenylenediamine) catalyst in the proportionate ratio and stirred well and then applied over the surface of the polythene A3 sheet. Then the first layer of jute is placed over the layer of resin and again a layer of resin is applied over the jute fiber over which the roller is rolled in order to remove air if any trapped between those layers. Next a layer of glass fiber is placed above the jute layer and resin is applied, followed by roller again to remove air trapped in between the layers if any. The above steps from 2 to 5 are repeated for the alternate layers of the jute and glass fibers until the required thickness of the specimen is obtained. Then the specimen is placed between the two plates and screwed in order to apply load and then left for 24 hours. The above steps are repeated for preparing the other to specimens of jute and glass fiber. Figure 2. Specimen A Figure 3. Specimen B Figure 4. Specimen All Rights Reserved 362

5 The composition of three specimens is as follows: Table 1. Composition of specimens Volume fraction(%) Resin Jute fiber Glass fiber Specimen A Specimen B Specimen C V. TESTS AND RESULTS The following lists of tests were conducted on the specimens: 1) Tensile Test 2) Compression Test 3) Flexural Test 4) Impact Test 5) Shear Test 6) Water absorption test 7) Flammability test 8) SEM Analysis Figure 5. specimens prepared for tests 5.1. Tensile Test Tensile test was conducted on the specimens according to the ASTM standard D638. The test procedure was carried out as per the standard [6].The test was carried out in a Universal Testing Machine of 40 Ton capacity. The observations made from the tensile test for each specimen are as follows: Table 2. Tensile test results Specimen A Specimen B Specimen C Maximum tensile load(kn) All Rights Reserved 363

6 The above tensile test results shows that the tensile load for specimen B is greater when compared with the other two specimens. Figure 6. specimens after tensile test 5.2. Compression Test Compressive test was conducted on the specimens according to the ASTM standard D695. The specimen was prepared according to the dimensions of the ASTM standard D695 and then the test was carried out [7]. The observations obtained from compressive test for each specimen are as follows: Table 3. Compressive Test Results MAXIMUM COMPRESSIVE LOAD(KN) SPECIMEN A SPECIMEN B SPECIMEN C The above compressive test results shows that the compressive load for C is greater when compared with the other two specimens. Figure 7. specimens after compression All Rights Reserved 364

7 5.3. Flexural Test Flexural test was conducted on the specimens according to the ASTM standard D790. The specimen was prepared for the flexural test accordingly as per the ASTM standard D790and flexural test was carried out [8]. The observations obtained from flexural test for each specimen are as follows: Table 4. Flexural Test Results MAXIMUM FLEXURAL LOAD(KN) SPECIMEN A SPECIMEN B SPECIMEN C The above flexural test results shows that the flexural load for specimen B is greater when compared with the other two specimens. Figure 8. Specimens after flexural test 5.4. Impact Test Impact test was conducted on the specimens according to the ASTM standard D256. The specimen was prepared accordingly for the impact test as per the ASTM standard D256 and impact test was carried out [9]. The observations obtained from flexural test for each specimen are as follows: Table 5. Impact test results SPECIMEN A SPECIMEN B SPECIMEN C IMPACT (J) The above shear test results shows that the shear load for specimen B is greater when compared with the other two specimens. Figure 9.specimens after impact All Rights Reserved 365

8 5.5. Shear test Shear test was conducted on the specimens according to the ASTM standard D2344. The specimen was prepared accordingly for the shear test as per ASTM standard D2344 and the shear test was conducted [10]. The observations obtained from flexural test for each specimen are as follows: Table 6. Shear Test Results SPECIMEN A SPECIMEN B SPECIMEN C MAXIMUM SHEAR LOAD(KN) The above shear test results shows that the shear load for specimen B is greater when compared with the other two specimens. Figure 10. Specimens after shear test From the above tests it was found that the specimen B is having better properties when compared with the Specimen A and specimen C. Hence the following tests were being carried out for the specimen B and the results were discussed Water absorption test Water absorption test was carried out according to the ASTM standard D570. The specimen was prepared as per the ASTM standard D570 [11] and water absorption test was carried out. The observations made from the water absorption test are as follows: Table 7.Water absorption test results WATER ABSORPTION (%) Flammability test Flammability test was carried out according to the ASTM standard E162. The specimens were prepared as per the ASTM standard E162 [12] and flammability test was carried out. The observation made from flammability test is as follows: Table 8. Flammability test results FLAMMABILITY(mm/min) All Rights Reserved 366

9 The test reports of the above tests are as follows; Figure 11. Test Report of tensile, compressive, flexural, shear and impact tests Figure 12. Test report of water absorption and flammability All Rights Reserved 367

10 5.8. SEM analysis SEM analysis is used to find out the fiber dispersion, fiber orientation and air voids formed inside the specimen. The specimens were prepared as per requirement for the SEM analysis and the SEM analysis was carried out. Figure 13. SEM analysis showing dispersion of glass fiber and epoxy resin orientation Figure 14. SEM analysis showing dispersion of fibers and All Rights Reserved 368

11 Figure 15. SEM analysis showing loose dispersion of resin round glass and jute fibers Figure 16. SEM analysis showing dispersion of resin around glass All Rights Reserved 369

12 Figure 16. SEM image showing binding between the resin and fibers Figure 17. SEM image showing binding between resin and fibers The above images obtained from the SEM analysis shows the binding between the fibers and resins and also the dispersion of the resin around the fibers and also it shows the presence of air voids All Rights Reserved 370

13 pores in between the resin and fibers at various magnification depths. From these images it can be inferred that there is some air voids present inside and also loose dispersion of resin around fibers, which can act as a source for the propagation of cracks inside the specimen. Hence further improvement in properties can be attained by improving the dispersion of fibers and reducing air voids inside the specimen. VI. CALCULATIONS 6.1. CALCULATION OF COMPRESSIVE The compressive strength of the specimens were calculated from the above test results are calculated using the following formula: Compressive load Compressive Strength= Area The results calculated from the above formula are as follows: Table 5.2: Compressive strength of specimens Specimen A B C Compressive Strength( N/mm²) CALCULATION OF FLEXURAL The flexural strength of the specimen were calculated using the following formula and the results obtained are as follows: 3FL Flexural strength, σ= 2bd 2 Table 9. Flexural Strength of specimens Specimen A B C FLEXURAL (N/mm²) CALCULATION OF SHEAR The shear strength of the specimen were calculated using the following formula and the results obtained are as follows: 3F Shear strength τ= 2bd Table 10. Shear strength of specimens SPECIMEN A B C SHEAR (N/mm²) All Rights Reserved 371

14 ULTIMATE TENSILE (MPa) International Journal of Recent Trends in Engineering & Research (IJRTER) Table 11. Overall properties of the specimens COMPRESSIVE (Mpa) IMPACT STREGTH (J) SHEAR (Mpa) FLEXURAL (Mpa) A B C SPECIMEN A SPECIMEN B SPECIMEN C 0 ULTIMATE TENSILE (MPa) (MPa) (J) (MPa) (MPa) COMPRESSIVE IMPACT SHEAR FLEXURAL Figure 18. Overall properties of the specimens VII. CONCLUSION The various mechanical properties such as tensile strength, compressive strength, flexural strength, shear strength and impact strength of the hybrid fiber composite of jute and glass fiber was determined. The properties such as water absorption and flammability of the specimen that is superior in its mechanical properties were determined and the characterization of the specimen were done by using SEM analysis for determining the fiber dispersion, fiber orientation, binding of resin with fibers and the presence of air gaps if any inside the specimen. From the results obtained it is found that this material can be used as a substitute for material used for automotive parts such as car dashboard,etc. REFERNCES I. K.L. Pickering, M.G. Aruan Efendy, T.M. Le., A review of recent developments in natural fiber composites and their mechanical performance,el sevier,2016. II. Vivek Mishra, Sandhyarani Biswas., Physical and Mechanical Properties of Bi-directional Jute Fiber epoxy Composites, Elsevier,2013. III. Najuma Abdul Razack, Lity Alen Varghese, The Effect of Various Hardeners on the Mechanical and Thermal Properties of Epoxy Resin,IJERT,2014. IV. Subhankar Biswas, Sweety Shahinu, Mahbub Hasan, Qumrul Ahsan, Physical, Mechanical and Thermal Properties of Jute and Bamboo Fiber Reinforced Unidirectional Epoxy Composites, All Rights Reserved 372

15 V. Maria Ernestina Alves Fidelis, Thatiana Vitorino Castro Pereira, Otávio da Fonseca Martins Gomes. The effect of fiber morphology on the tensile strength of natural fibers,elsevier,2013. VI. Standard Test Method for Short-Beam Strength of Polymer Matrix Composite Materials and Their Laminates VII. Standard Test Methods for Flexural Properties of Unreinforced and Reinforced Plastics and Electrical Insulating Materials VIII. Standard Test Methods for Determining the Izod Pendulum Impact Resistance of Plastics IX. Standard Test Method for Tensile Properties of Plastics X. Standard Test Method for Compressive Properties of Rigid Plastics. XI. Standard Test Method for Water Absorption of Plastics XII. Standard Test Method for Surface Flammability of Materials Using a Radiant Heat Energy All Rights Reserved 373