L natural fiber composites. It had. Synthesis and Mechanical Characterization of Processed Coconut Shell Particulate Reinforced Epoxy Matrix Composite

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PhD Profesor School of Mechanical & Building SciencesVIT University, Chennai Synthesis and Mechanical Characterization of Processed Coconut Shell Particulate Reinforced Epoxy Matrix Composite

boron etc.) in composites tends to affect environment, on the other hand natural fibers (Coir, jute, flax etc.

1 PhD Profesor School of Mechanical & Building SciencesVIT University, Chennai Synthesis and Mechanical Characterization of Processed Coconut Shell Particulate Reinforced Epoxy Matrix Composite Abstract Fiber reinforced polymer composites have acquired a dominant place in variety of applications because of their high specific strength and modulus The use of synthetic fibers (glass, aramid, boron etc.) in composites tends to affect environment, on the other hand natural fibers (Coir, jute, flax etc.) are environmentally superior to synthetic fibers The objective of this study is to investigate the synthesis technique and mechanical characterization of processed coconut shell filler particulate reinforced with epoxy matrix. Fiber reinforced polymer composites have acquired a dominant place in variety of applications because of their high specific strength and modulus The tensile, flexural and compression tests of natural composites based on coconut shell filler particles at three different filler contents viz.10%, %, 30% and 40%, were carried out using universal tensile testing machine according to ASTM. The study revealed that increasing the filler particle improves the tensile strength characteristics and suitable flexural strength exhibiting bio-composite also validated. Keywords : Coconut Shell, Epoxy, Tensile Test, Three Point Bending Test, Compression Test ot of research was carried out on L natural fiber composites. It had become a material of choice as an alternative to other traditional materials and has found applications in many sectors. Since the 1990s, natural fiber composites are emerging as realistic alternatives to glass-reinforced composites in many applications. Natural fiber composites have also claimed to offer environmental advantages such as reduced dependence on non-renewable energy sources, lower pollutant emissions, lower greenhouse gas emissions, enhanced energy recovery, and end of life biodegradability of components. Thus such superior environmental performance is an important driver of increased future use of natural fiber composites [1]. As a

Technology result, a large amount of research has been dedicated to the use of natural fibre as a substitute for glass, carbon and synthetic fibres; driven by potential weight saving, lower raw

2 Technology result, a large amount of research has been dedicated to the use of natural fibre as a substitute for glass, carbon and synthetic fibres; driven by potential weight saving, lower raw material price, and ecological advantages of using resources which are renewable [2,3]. Many research articles have reported the use of various natural fibers, mostly derived from the bast or stem of the plants, including jute, sisal, flax and hemp. In the area of bio-composite many research has been carried out and some of them are explained below. Those hybrid composite areas were helped to prepare a mono bio-composite with coconut filler and epoxy resin. A research has been carried out on preparation and characterization n preparation and characterization of chemically modified jute coir hybrid fiber reinforced with epoxy resin. The maximum improvement on the properties was achieved for the hybrid composite containing the jute coir content of 50: 50 [4].Natural fiber based composite have been successfully manufactured by several methods wet lay up,resin transfer moulding and finally vacuum assisted resin infusion[10,11]. the inherent incompatibility between natural fibres and synthetic matrix resulting in poor fibre matrix adhesion is often an issue which needs to be addressed in order to improve the mechanical performance of the resulting bio-composites. The quality of fibre matrix adhesion can be enhanced either through surface treatment or via improvement of manufacturing processes. For instance, curing of composites at higher temperatures will further lower the viscosity of the resin, which in turn will increase the wetting of the fibres and improve the fibre matrix adhesion in composites [12]. A Comparison between Compression Molding and Resin Transfer Molding was done and the properties were evaluated. Tensile and flexural properties are found to be higher in resin transfer molded composites whereas the impact strength of RTM composites are slightly lower than that of CM composites [10]. Mechanical properties of ukam, banana, sisal, coconut, hemp and E-glass fiber reinforced laminates were evaluated to assess the possibility of using it as new material in engineering applications From the above literature it can be seen that not much research has been done on the natural fiber with small different combination of filler. The research carried out in the past on coconut composites is very limited. Coconut shell is one of the most important natural fillers produced in tropical countries like India, Malaysia, Indonesia, Thailand and Sri Lanka. Many works have been devoted to use of other natural fillers in composites in the recent past and coconut shell filler is a potential candidate for the development of new composites because of their high strength and modulus properties. Composites of high strength coconut filler can be used in the broad range of applications as, building materials, marine cordage, fishnets, furniture, and other household appliances filler particulates Among different natural fibers, coconut filler are prominent reinforcing material in fabrication of different types of polymer based composites, due cost effectiveness, high strength, etc Materials and Methods A. Materials Coconut shell filler particulate of different weight percentage (10g, g, 30g, 40g),Pilogrip epoxy resin with Triethylene Tetra Amine (TTA) hardener. Epoxy resin is the one of the most used thermosetting polymers which are widely used in fiber reinforced matrices. They exhibit high tensile strength and modulus, uncomplicated processing, good thermal and chemical resistance, and dimensional stability due to the highly cross linked polymer bonding.[arabic] Coconut shell particulate is made from versatile part of the coconut, the shell which is in organic nature. Since it has good durability characteristics high toughness and abrasion resisistant properties. The shell is similar to hard woods.the coconut shell composite material offers Strength and rigidity Light in weight Eco friendly nature Renewable and abundant nature The main disadvantages are Moisture content Non uniform filler size Not suitable for higher temperature application Susceptible to fungi attack B. Methodology Procurement of Materials The experiment starts with a procurement of epoxy and coconut shell specimen and hardener mainly. Ten piece of coconut shell were procured and crushed manually with the diameter ranging from 4 to 7mm.The density of the shell is 1.6g/cm3.The crushed particulate contain varies impurities and it is removed by washing in water, thereafter it is dried properly by exposing to the sunlight for 24 hours until the entire moisture gets evaporated. The epoxy and hardener were procured from Janki Enterprise Chennai. The weight ratio of resin and hardener were 10:1 Fig1. Crushed Coconut Shell C. Preparation of Epoxy / Coconut Filler Composite Samples Mould used in this study prepared with wooden material. They were open moulds having the dimension of m m x 3 0 m m x 8 m m. i t w i l l accommodate the liquid form of composite material. The dimensions and shapes of cavities were made according to the size and shape of the samples as per ASTM Standard tensile testing and for flexural testing. Epoxy and hardener were mixed in the container and mixed thoroughly for 10 to 15 minutes for the uniform distribution of hardener otherwise fast exothermic reaction takes place and entire process gets spoiled. After that coconut shell particulate added to the 32 December 13

mixture and stirred well for 10minutes for viscosity matching of particulate and resin.

Finally, the mixture was poured into the mould and left at room temperature for 48 hours until the mixture was hardened.

Test Specimen During tension test a uniaxial load was applied from both the ends of specimen. The gauge length of 100mm was taken while testing.

$Tensile Testing Machine (UTM) factors such as the stress strain behaviorsof fiber and matrix phases, the phase volume fractions, the filler concentration, the distribution and orientation of the r$

3 mixture and stirred well for 10minutes for viscosity matching of particulate and resin. Before the mixture is poured into the mould cavity a releasing agent (Mansion polish) were applied to the wooden mould for easy removal of specimen. Finally, the mixture was poured into the mould and left at room temperature for 48 hours until the mixture was hardened. When the composite were hardened, it was removed from the mold and finally composite were cured for 48 hours in room temperature. Fig 2.Test Specimen During tension test a uniaxial load was applied from both the ends of specimen. The gauge length of 100mm was taken while testing. For bending test the distance between the supports was 100mm. The speed of stroke was 5mm/min. Fig. 3.Tensile Testing Machine (UTM) factors such as the stress strain behaviorsof fiber and matrix phases, the phase volume fractions, the filler concentration, the distribution and orientation of the r fillers relative to one anotherthe result of stress strain graph for tensile test of different shell particulate weight percentage are plotted and shown in below figures. Fig. 6. Test Analysis of 40g Shell Particulate Fig. 4. Three Point Bending Machine Fig. 7. Test Analysis of 30g Shell Particulate Experimental Tensile strength indicates the ability of a composite material to withstand forces that pull it apart as well as the capability of the material to stretch prior to failure. Flexural strength is the ability material to withstand bending forces applied perpendicular to its longitudinal axis. Compression test was also carried out to determine the behavior of material under crushing load. The tension test was carried on Universal testing machine (UTM) to measure the tensile strength of Composite material, Three different filler contents by weight were used namely 10%,%,30% and 40% were tested,bending strength was measured on 3-point bending test machine. Figure (2) shows the universal testing machine and 3-point bending machine is shown in figure (3). Fig. 5. Compression Testing Machine Results and Discussion Tensile Properties of Coconut Shell and Epoxy Filler Mechanical properties of the natural filler composites depend on several Fig. 8. Test Analysis of g Shell Particulate Fig. 9. Test Analysis of 10g Shell Particulate

4 Technology Composite Weight Fraction g) TABLE 1 : TENSILE PROPERTIES OF BIO COMPOSITE MATERIAL Yielding Load KN) The ultimate engineering stress, in tension, that may be sustained without fracture in known as maximum tensile stress. The change in length of a specimen (in the direction of applied stress before fracture) divided by its original length in known to maximum tensile strain. The effect of coconut filler content on maximum tensile stress, strain. The increase of the filler content, results in the increase in tensile stress and tensile modulus of elasticity. This is due to the fact that coconut filler particles strengthen the interface of resin matrix and filler materials. The maximum tensile strength for 40% filler composite was higher ( N/mm2) compared to other three combinations. Flexural Strength Test The test specimen was placed on the simple supports of a UTM machine. It was made sure that the ends of the specimen were located at the midpoint of the supports. Loading nose applies the load on the specimen at mid span. The loading is continues until the failure of the specimen. Flexural strength = 3PL/ (2bh2) P Load applied on mid span of the specimen (N). L Span length between supports (mm) b Width of the specimen (mm) h Thickness of the specimen (mm) Flexural strength in N/mm2 The results of Load v/s Elongtaion graph for different combination are plotted below. Fig. 10. Test Analysis of 40 g Specimen Tensile Strength N/mm2) Yield Stress N/mm2) FIG 11. Test Analysis of 30 g Specimen FIG 12. Test Analysis of g Specimen FIG 13. Test Analysis of 10 g Specimen The load deflection graph not only gives the maximum deflection for a particular specimen, but when compared with different specimens it shows the change in load bearing capacity (for different configurations). It can be seen that the material fails quickly as soon after it reaches maximum load bearing capacity (load v/s time).the maximum flexural strength is occurred at 30 g specimen of N/mm2.So when we keep on adding the filler particle it will reduce the flexural strength characteristics. Here we got optimum value at 30 g specimen. Compression Test W h e n s u b j e c t e d t o s t a t i c compression, the behaviour of most materials is in many ways similar to that in tension. The stress strain curve changes exhibited due to ductility property of material An axial compressive force can easily be applied by pressing the specimen between two parallel platens making contact with two ends of the specimen. Tests are carried out in the universal testing machine fitted with the compression plate. T h e r e w e r e t w o w e i g h t configuration composite were undergone the compression test. The load v/s time graph was plotted and r e s u l t a r e s h o w n i n b e l o w. A m o n g t h o s e t w o d i f f e r e n t combination, 40 g bio-composite exhibit better compressive strength of N/mm2. FIG 14. Compression Test Analysis of 40 g TABLE 2 : FLEXURAL TEST RESULTS Composite Load At Transverse Weight Peak Strength Fraction kn) N/mm2) g) Conclusion T h e t e n s i l e, f l e x u r a l a n d compressive test of epoxy composite reinforced with synthesised coconut shell filler particulate were carried out in this research and following conclusions are drawn from the study. 34 December 13

$In tensile testing, coconut filler particulate demonstrated linear behavior with sharp fracture and exhibit higher tensile strength for higher filler particulate specimen In flexural testing, filler$

5 The tensile and flexural strengths of the epoxy coconut filler composites were affected by the amount of filler in the composites. The more the filler content, the higher the strength. In tensile testing, coconut filler particulate demonstrated linear behavior with sharp fracture and exhibit higher tensile strength for higher filler particulate specimen In flexural testing, filler composites demonstrated slightly nonlinear behavior prior to sharp fracture and 30g of shell particulate reinforced composite exhibit higher flexural strength. The effect of flexural strength may happens due to to the post curing process and pouring defects during the fabrication. In tensile and flexural stresses, the strains decrease with the increase in the filler contents due to the fact that the materials have become harder with the increase in filler contents. The processed material has less ductile behavior and it is proposed for the application were compressive stress comes into play (Home appliance like table. bunch etc) Acknowledgment The authors would like to thank the School of Mechanical and Building Sciences SMBS, VIT University Chennai India for making available the laboratory facilities to conduct the research work. References (1) S.V.Joshi et al., Are natural fiber composites environmentally superior to glass fiber reinforced composite?, Part A 35: applied science and manufacturing, (04) (2) S. M. Sapun, M. Harini, M. A. Maleque,. Mechanical properties of epoxy reinforced coconut shell particulate composite. The Arabian Journal for Science and Engineering, Volume 28, Number 2B. (3) J. Breckling, Ed., The Analysis of Directional Time Series: Applications to Wind Speed and Direction, ser. Lecture Notes in Statistics. Berlin, Germany: Springer, 1989, vol. 61. (4) Sudhir Kumar Saw et al., Preparation and Characterization of Chemically Modified Jute-Coir Hybrid Fiber Reinforced Epoxy Novolac Composites. Journal of Applied Polymer Science, Vol. 125, (12) (5) Dr.S.Jose,Dr.E.V.Mathew.Metallurgy and Material science (6) Alok Satapathy et al., Processing and Characterization of Jute-Epoxy Composite Reinforced with SiC Derived from Rice Husk. Journal of REINFORCED PLASTICS AND COMPOSITES, Vol. 00, No. 00/09. (7) Dixit S. and Verma P., The effect of Hybridization on Mechanical Behaviour of Coir/Sisal/Jute Fibres Reinforced Polyester Composite Material, Research Journal of Chemical Sciences, Vol.2 (6), 91-93, June (12). ( 8 ) D. C h a n d r a m o h a n a n d K. Marimuthu, A review on natural fibers, International Journal of Research and Review in Applied Sciences, Vol.8, Issue 2, August 11. (9) S. V. Prasad, C. Pavithran, P. K. Rohatgi, Alkali treatment for coir fibres for coir-polyester composites, Research regional laboratory, India, 1983, pp (10) Olusegun David Samuel. et al, Assessing Mechanical Properties of Natural Fibre Reinforced Composites for Engineering Applications, Journal of Minerals and Materials Characterization and Engineering, 12, 11, (11) Maries Idicula, Natural Fiber Hybrid Composites-A Comparison between Compression Molding and Resin Transfer Molding, polymer composites-09. (12) Tara Sen, H. N. Jagannatha Reddy, Application of Sisal, Bamboo, Coir and Jute N a t u r a l C o m p o s i t e s i n S t r u c t u r a l Upgradation. International Journal of Innovation, Management and Technology, Vol. 2, No. 3, June 11

Key words: Weight fractions, Filler, Fiber, Flexural strength, Hand lay-up

$Key words: Weight fractions, Filler, Fiber, Flexural strength, Hand lay-up$ Influence Of Fiber/Filler Particles Reinforcement On Epoxy Composites B.H.Manjunath, Dr. K Prahlada Rao Department of Mechanical Engineering, Proudhadevaraya Institute of Technology. Hospet-583203, India