Study on Mechanical Properties of Glass/Satin/Epoxy Hybrid Composites Fabricated Through Vacuum Bag Moulding

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1 2017 IJRTI Volume 2, Issue 6 ISSN: Study on Mechanical Properties of Glass/Satin/Epoxy Hybrid Composites Fabricated Through Vacuum Bag Moulding 1 Prasad Ram Devali, 2 Preetam Pai, 3 Shreyas Subhas Kamath, 4 Vignesh B Students, Department of Mechanical Engineering Canara Engineering College, Mangalore, India. Abstract In many engineering applications hybrid composite materials have the great potential. The designer can obtain the required properties offered by the hybrid polymer composites in a controlled considerable extent by the choice of fibers and matrix. By selecting different kinds of fiber incorporated in same resin matrix, the properties can be altered in the material. In the present investigation, the study on different mechanical properties of satin and glass fibers reinforced epoxy hybrid composite were done. For the fabrication of hybrid composite materials, the vacuum bagging technique was adopted. As per ASTM and ISO standards, the mechanical properties such as tensile strength, tensile modulus, and strain at break, flexural strength, and impact strength of the hybrid composites were determined. I. INTRODUCTION A Composite material is made from two or more constituent materials with significantly different properties. When combined, produce a material characteristics different from the individual components.new material may be preferred because these materials are stronger, lighter, or less expensive comparatively. Researchers have also started to actively include actuation, sensing,communicationand computation into it, known as Robotic Materials. Typical engineered composite materials include: Mortars, Concrete Reinforced plastics, such as fiber-reinforced polymer Metal composites Ceramic composites (composite ceramic and metal matrices) Composite materials are generally used for buildings, bridges, and structures such as boat hulls, swimming pool panels, racecar bodies, shower stalls, bathtubs, storage tanks, imitation granite and cultured marble sinks and countertops. The most advanced examples perform routinely on spacecraft and aircraft in demanding environments. Specimen Preparation Releasing agent (petroleum jelly) is applied to the mould of dimension of 300*300*3mm. Epoxy (L-12) & hardener (K-9) is mixed in the proportion of 1:10 by volume. Glass fibre (7 mil) & satin is cut according dimensions. According to calculation of number of layers of material required for the specific specimen, the layers are applied one after the other. The mixture of epoxy hardener is applied on each layer, thereafter the next layer is placed. When the required layers are applied breather sheet is placed above the mould so that it absorbs the epoxy. Then the mould is placed in a vacuum bag, which is sealed. The nozzle of vacuum bag is connected to vacuum pump &vacuum pressure is controlled by controlling valve. The layers of the composite are sandwiched due to suction of the vacuum pump. The setup is left to dry for 24 hours. The obtained specimen is cut according to ASTM and ISO standard. The specimen is been tested for Tensile Test (ASTM D3039), Flexural Test (ASTM D790), Impact (ISO 179-1:2010). Analysis of results and comparison is done. II. LITERATURE SURVEY Uniform pressure is created due to vacuumbagging which eliminates putti pooling or putties starved areas due to the unequal clamping pressure. Maximum mechanical properties is produced due to the total attachment of core to facings allowing a sandwich to develop. The quality of the composite is improved i.e. fiber to volume ratio, excellent surface finish, usage of multiple layers of fiber, improved strength and stiffness etc. The above properties made to implement vacuum bagging fabrication process to obtain better material performance at a reasonable cost in the industries [1].Modification of large number of polymers with nano fillers have taken place for either reinforcing them or for introducing multi-functionality. Considering the altered process characteristics, the use of such modified polymers for structural composites with fiber reinforcement has been a IJRTI International Journal for Research Trends and Innovation ( 436

2 2017 IJRTI Volume 2, Issue 6 ISSN: challenge. Rheological changes of the modified matrix will impede the stringent process requirements, and in turn large scale manufacturing of composites may not be feasible. While liquid composite molding techniques have limitations to process nanofillers modified polymer resins, processes such as resin film infusion can pave ways towards reinforced and multifunctional hybrid composites [2]. According to the research study on mechanical properties, especially tensile strength, flexural strength and impact strength. Impact toughness notch across the laminates gives greater value than that of along the notch. The value of impact toughness for unfilled glass composite is higher than the filled composites. With the addition of filler material, the value of Tensile, Bending and Impact strength increases [3]. The mechanical properties of G10 glass-epoxy composites and were determined in compression and tension tests. Determination of modulus values determined by fitting a straight line to the initial linear portion of the stress-strain curves from weight and volume measurements, the volume fraction of glass was estimated to be about 56 percent [4].Vacuum bag method has fabricated the carbon fiber and glass fiber reinforced hybrid composites.the experimental evaluation of mechanical properties like tensile strength, flexural strength and micro hardness of hybrid composites as per ASTM standards have been done. The carbon fiber reinforced composite has higher micro hardness than the other composites. The tensile properties and the breaking load are studied and measured. The ultimate tensile strength, yield strength and peak load of composite enhanced significantly by the inclusion of carbon fiber mat reinforced polymeric composite. Carbon fiber reinforced composite possesses higher ductility than the other composites [5]. III. METHODOLOGY The mould of dimension 300mm*300mm*3mm is applied with releasing agent. The satin & glass fiber material are cut according to dimension. The epoxy (L-12) andhardener (K-9) are mixed in the ratio of 10: 1 by volume. Alternate layers of glass fiber and satin is applied. Then the mould is placed in the vacuum bag and then it is sealed. Vacuum bag creates suction and provides uniform clamping pressure over the surface of specimen. The specimen is cured for 8 hours. Fig 1.Vacuum bag moulding process IV. EXPERIMENTATION Following table shows the specimen composition: Specimen Epoxy (%) Satin (%) Glass Fiber (%) A - B - C D Table 1. Specimen composition Application of epoxy,hardener mixture on satin and glass fiber is shown in Fig 2. Final setup with vacuum bag and vacuum pump is shown in Fig 3. The final specimen obtained is shown in Fig 4. IJRTI International Journal for Research Trends and Innovation ( 437

3 2017 IJRTI Volume 2, Issue 6 ISSN: Fig 2. Application of epoxy, hardener mixture Fig 3. Final setup Fig 4. Specimen IJRTI International Journal for Research Trends and Innovation ( 438

4 IJRTI Volume 2, Issue 6 ISSN: TENSILE TEST (ASTM D3039) 140 Fig 5. Tensile Test (ASTM D3039) By this test determination of the in-plane tensile properties of polymer matrix composite materials strengthened by high-modulus fibers can be obtained. The composite material forms are limited to continuous fiber or discontinuous fiber-reinforced composites in which the laminate is balanced and symmetric with respect to the test direction. FLEXURAL TEST (ASTM D790) Fig 6. Flexural Test (ASTM D790) The flexural test is used to determine the flexural properties of both reinforced and unreinforced plastics, as well as high modulus composites and electrically insulating materials, utilizing a three-point loading system to apply a load to a simply supported beam. The method is generally applicable to rigid as well as semi-rigid materials, but flexural strength cannot be found out for the yield in the outer surface of the test specimen within the 5.0 % strain limit or those materials that do not break. IMPACT TEST (ISO 179-1:2010) 60 Fig 7. Impact Test (ISO 179-1:2010) The method can be used to investigate the behavior of specified types of specimen under the impact conditions defined and for estimating the brittleness or toughness of specimens within the limitations inherit in the test conditions. It can also be used for the determination of comparative data from similar types of material. IJRTI International Journal for Research Trends and Innovation ( 439

5 Flexural Strenggth (MPa) Ultimate tensile strength (Mpa) 2017 IJRTI Volume 2, Issue 6 ISSN: V. RESULTS TENSILE STRENGTH specimen A specimen B specimen C specimen D Specimen Fig 8. Tensile Strength It is observed that from the Fig 8.graph the tensile strength varies from 122Mpa to 291MPa.The specimen B shows % increase in Tensile Strength compared to specimen C. GRP (Glass Reinforced Polymer) composite exhibits highest tensile strength. The increase in tensile strength can be attributed to the good interfacial bonding between the glass fiber and the matrix. FLEXURAL STRENGTH specimen A specimen B specimen C specimen D Specimen Fig 9. Flexural Strength IJRTI International Journal for Research Trends and Innovation ( 440

6 Impaact Strength (MPa) 2017 IJRTI Volume 2, Issue 6 ISSN: It is observed that the Fig 9. flexural strength varies from 101MPa to 283 Mpa. Specimen a shows % increase in flexural strength compared to specimen B. Satin reinforced composite exhibits highest flexural strength. IMPACT STRENGTH specimen A specimen B specimen C specimen D Specimen Fig 10. Impact Strength It is observed from the Fig 10.That the impact strength varies from Mpa to Mpa. Specimen C shows 93.82% increase compared to Specimen B. Hybrid components show better impact strength than single reinforced composites. VI. CONCLUSION AND FUTURE WORK Indicates that GRP epoxy composites has exhibited the highest tensile strength and tensile modulus. While 20% glass fiber and 30% satin reinforced epoxy hybrid composite demonstrated highest strain percentage. Strain reinforced composites exhibited highest flexural strength followed by hybrid composites, while this suggest that glass satin hybrid composites yields optimal flexural properties. The hybrid composites exhibited better impact strength compared to single type fiber reinforced composites. The obtained results suggest that, the hybrid composites with constituents of glass fiber and satin give optimal mechanical properties such as tensile strength, satin percentage flexural strength except tensile modulus. In Automotive sector of fiber/glass/epoxy springs for heavy trucks and trailers. In chemical industry for the manufacturing of composite vessels for liquid gas alternative fuel vehicles. In the manufacturing of underground storage tanks. In Electrical and Electronics in third rail covers for underground railways. In sports for the golf and polo rods It can be used in the filament winding. REFERENCES [1] M. Lakshmi Aparna, Dr. G. Chaitanya, Dr. K. Srinivas and Dr. J. Appa Rao, Fabrication of Continuous GFRP Composites using Vacuum Bag Molding Process, International Journal of Advanced Science and Technology,Vol.87 (2016), pp [2] AnoopAnand and Makarand Joshi, Structural Composites Hybridized with Nanofillers, Journal of the Indian Institute of Science, Vol.95:3 (2016), pp [3] Patil Deogonda, Vijaykumar N Chalwa, Mechanical Property of Glass Fiber Reinforcement Epoxy Composites, International Journal of Scientific Engineering and Research (IJSER), Vol.1 (2013) Paper ID: J [4] K.RaviChandar&S.Satapathy, Mechanical Properties of G-10 Glass Epoxy Composite, Institute for Advanced Technology The University of Texas at Austin IAT.R 0466 (2015) [5] T D Jagannatha and G Harish, Mechanical properties of carbon/glass fiber reinforced epoxy hybrid polymer composites, Int. J. Mech. Eng. & Rob., Vol. 4, No.2 (2015) IJRTI International Journal for Research Trends and Innovation ( 441