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Electrical Conductivity Studies of Glass Fiber Reinforced Polymer Composites
Available online at www.sciencedirect.com
ScienceDirect Materials Today: Proceedings 5 (2018) 3229–3236
www.materialstoday.com/proceedings
ICAMA 2016
Electrical Conductivity Studies of Glass Fiber Reinforced Polymer Composites Manju M Ba, Sai Vignesha, Nikhil K Sa, Sharaj A Pa, Madhav Murthy*a a
BMS College of Engineernig, Bangalore 560019, India
Abstract Polymer matrix composite is a material consisting of a polymer (resin) matrix combined with a fibrous reinforcing dispersed phase. Polymer Matrix Composites are very popular due to their low cost and simple fabrication methods. Use of non-reinforced polymers as structure materials is limited by low level of their mechanical properties: tensile strength of one of the strongest polymers - epoxy resin is 20000 psi (140 MPa). In addition to relatively low strength, polymer materials possess low impact resistance. Two main kinds of polymers are thermosets and thermoplastics. Thermosets have qualities such as a well-bonded three-dimensional molecular structure after curing. They decompose instead of melting on hardening. Merely changing the basic composition of the resin is enough to alter the conditions suitably for curing and determine its other characteristics. They can be retained in a partially cured condition too over prolonged periods of time, rendering Thermosets very flexible. Thus, they are the most suited as matrix bases for advanced conditions fiber reinforced composites. Thermosets find wide ranging applications in the chopped fiber composites form particularly when a premixed or molding compound with fibers of specific quality and aspect ratio happens to be starting material as in epoxy, polymer and phenolic polyamide resins. Thermoplastics have one- or twodimensional molecular structure and they tend to at an elevated temperature and show exaggerated melting point. Another advantage is that the process of softening at elevated temperatures can reversed to regain its properties during cooling, facilitating applications of conventional compress techniques to mold the compounds.
© 2018 Elsevier Ltd. All rights reserved. Selection and Peer-review under responsibility of International Conference on Advanced Materials and Applications (ICAMA 2016). Keywords: FRP Composites; Electrical conductivity; Insulating properties; S-Glass fibers; E-Glass fibers.
1. Introduction: Composite materials produce a combination of properties of two or more materials that cannot be achieved by either fiber or matrix when they are acting alone[1]. * Corresponding author. Tel. 9482852100
E-mail address: [email protected] 2214-7853 © 2018 Elsevier Ltd. All rights reserved. Selection and Peer-review under responsibility of International Conference on Advanced Materials and Applications (ICAMA 2016).
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Physical and chemical properties of the constituent materials differ significantly. Composites are most often used because of their light weight, reduction of higher fatigue resistance. Composites consist of two main constituents: a.
Matrix: The matrix is basically a homogeneous and monolithic material in which a fiber system of a composite is embedded. It is completely continuous. The matrix provides a medium for binding and holding reinforcements together into a solid. It offers protection to the reinforcements from environmental damage, serves to transfer load, and provides finish, texture, color, durability and functionality.
b. Reinforcements: Reinforcement is basically the discontinuous or dispersed phase of the composites. It is responsible for composites high strength and stiffness. The most important reinforced fibers in current use are glass, graphite, carbon and Kevlar. Composite materials are usually classified by the type of reinforcement and the type of matrix they use. Glass fiberreinforced polymer (GFRP) composites are the most commonly used composite materials. The mechanical behavior of an FRP composite basically depends on the fiber strength, matrix strength and the interface bonding to enable stress transfer. Suitable compositions and orientation of fibers help in achieving desired properties and functional characteristics of GFRP composites that are equal to steel, higher stiffness than aluminum and a specific gravity equal to one-quarter of steel. The properties of composites depend on the fibers laid or laminated in the matrix during the composite preparation[2]. The various GF reinforcements in the composites have been produced to enhance the mechanical properties of the composites. GF reinforced composite materials have very good environmental resistance, higher damage tolerance for impact loading, high specific strength and stiffness. Epoxy resins are widely used because they have high chemical/corrosion resistant properties and low shrinkage on curing. Several factors influence the energy dissipation of FRP composites such as fiber volume, fiber orientation, matrix material, temperature, moisture and other properties like thickness of lamina and thickness of the composites. All FRP composites have temperature-dependent mechanical properties. E-Glass or electrical grade glass was developed for standoff insulators for electrical wiring. E-Glass is a low alkali glass with a typical nominal composition of 54% of SiO2, 14% of Al2O3, 22% of CaO + MgO, 10% of B2O3 and less than 2% of Na2O+K2O. Even though E-glass has excellent insulating properties, its mechanical properties are not sufficient in many instances. S-Glass has a nominal composition of 65% of SiO2, 25% of Al2O3, 10% of MgO. Sglass has superior mechanical strength when compared to E-glass but lacks in insulating properties[3]. Hence Sglass is used in applications that require improved mechanical properties compared to E-glass based composites. But there is a compromise in electrical properties [4]. To tackle this problem, this article aims to combine S-glass and Eglass and to evaluate its electrical properties at room temperature. 2.
Methodology:
E glass and S glass fibers were used as reinforcement in the preparation of this hybrid. Epoxy resin LY556 was used as a matrix. To facilitate and speed up the hardening process, hardener HY951 was used. The fibers used for the experiment were bi directional, cross stitched. A wooden board of required dimensions was used as a mold. Acrylic sheet was wrapped around the mold so that the prepared composite does not adhere to the board. Ten parts of LY556 epoxy resin was mixed with one part of HY951 hardener, this mixture was stirred thoroughly to ensure a proper mix. Fibers were cut to the required dimensions using composite shear.The prepared mixture is poured on to an acrylic sheet and spread to obtain an even coat. First layer of the fiber was placed on the matrix coated mold. The fiber is pressed so that the resin mixture (matrix) impregnates it. Then using a roller the resin is evenly spread. More resin is poured and spread evenly and another layer of fiber is placed and the process is repeated until a desired configuration is obtained. This process can also be done for required thickness.
Manju M B et.al/ Materials Today: Proceedings 5 (2018) 3229–3236
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Three different glass fiber configurations were selected for the experimental purpose. They are: a) S Glass Fiber Composite b) S-E-S-E Hybrid Glass Fiber Composite c) S-S-E-E Hybrid Glass Fiber Composite. The prepared composites are allowed to dry for about 8-10 hours. The dried composites are cut into pellets of 2cm diameter using Abrasive water jet machine by a suitable coordinate input data. The pellets are silver coated on both the sides since the material is non-conductive. Electrical properties at room temperature are experimentally found using an impedance analyzer. The 6500B series of precision impedance analyzer provides impedance measurement capability from 20Hz to 5MHz. This range of functions enables us to accurately characterize a component over a wide range of frequencies. The instrument can be used in 2 modes, graphical and meter. The GUI enables measurement parameters to be easily modified. Properties such as admittance, inductance, capacitance, conductance and impedance are calculated for various frequencies ranging from 102 – 105.
Figure 1: Wayne Kerr 6500B Precision Impedance Analyzer (Reference: 8)
3. Results and discussion: The variation of the above mentioned properties against frequency, for the above mentioned materials, have been drawn and analyzed. Here the Frequency (x-axis) is taken in logarithmic scale. a.
Capacitance and Dielectric Constant:
Dielectric Constant is used to determine the ability of an insulator to store electrical energy. It is the ratio of capacitance of a capacitor with test material as the dielectric to the capacitance of a capacitor with a vacuum as the dielectric. For materials that are to be used to insulate electrical components the dielectric constant should be low. For materials that are to be used as a dielectric in a capacitor, the dielectric constant should be high so that the capacitor dimensions can be minimized. Capacitance is the ability of a body to store an electrical charge. It is also the ratio of the change in an electric charge in a system to the corresponding change in its electric potential. A material with a large capacitance holds more electric charge at a given voltage, than one with low capacitance.
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Manju M B et.al / Materials Today: Proceedings 5 (2018) 3229–3236
As the frequency increases, the capacitance and dielectric constant for all three compositions, unsteady at first, remains constant after a certain frequency which can be called as threshold frequency. From the graph, it can be observed that after the threshold frequency, SSEE composition has the least dielectric constant and S - glass has the highest dielectric constant and capacitance for a particular frequency. Hence it can be inferred that SSEE composite is the best insulator out of the three compositions.
Figure 2: Capacitance v/s Frequency
Figure 3: Dielectric Constant v/s Frequency
Manju M B et.al/ Materials Today: Proceedings 5 (2018) 3229–3236
b. Admittance, Conductance and Susceptance:
Figure 4: Admittance v/s Frequency
Figure 5: Conductance v/s Frequency
Figure 6: Susceptance v/s Frequency
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Admittance is an expression of the ease with which alternating current flows through a system or substance. Admittance is a vector quantity which comprises of two independent scalar phenomena: conductance and susceptance. Conductance is a measure of the ease with which charge carriers can pass through a substance. Conductance is observed with both Alternating current and direct current. Susceptance is an expression of the readiness with which a system or substance releases stored energy as the current and voltage fluctuate. It is observed only for AC. When AC passes through a component that contains susceptance, energy might be stored and released in the form of a magnetic field, in which case the susceptance is inductive, or energy might be stored and released in the form of an electric field, in which case the susceptance is capacitive. As the frequency increases, Admittance, conductance and susceptance remains constant for all the three compositions and after a threshold value is crossed it rises exponentially with S Glass fiber composition having the highest slope and SSEE hybrid glass fiber composition having the least slope. Hence S-glass fiber has the higher admittance when compared to other two compositions. From this it can be inferred that addition of E glass reduces admittance, conductance and susceptance. c.
Impedance, Reactance and Resistance:
Resistance is a force that tends to resist the flow of electrical current. The more resistive a resistor is the more it restricts the flow of electricity through it. Resistance needs to be considered irrespective of whether DC or AC flowing through the circuit. Reactance comes into existence only when AC is flowing through a circuit. It is the inertia developed against the motion of electrons due to the flow of AC. There are two types of reactance: Capacitative reactance and inductive reactance. Impedance is actually the overall opposition to current presented by the circuit. Impedance of a circuit is the square root of the sum of the squares of the resistance and reactance. As the frequency increases, for all the three compositions, resistance of the materials decreases and becomes constant after a threshold value has been crossed. Here SSEE hybrid glass fibre composition has the highest slope and SESE hybrid glass fibre composition has the least slope meaning to say SESE hybrid glass fibre composition retains its resistance the longest among the taken three glass fibre compositions.
Figure 7: Resistance v/s Frequency
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Reactance is negative for all the three compositions. As the frequency increases, impedance of the materials increases and after a threshold value has been crossed it becomes constant. Here S Glass fiber composition has the highest slope and SSEE hybrid glass fiber composition has the least.
Figure 8: Reactance v/s Frequency
As the frequency increases, impedance of the materials decreases and becomes constant after a threshold value has been crossed. Here SSEE hybrid glass fibre composition has the highest slope and S Glass fibre composition has the least slope meaning to say S Glass fibre composition retains its impedance the longest among the taken three glass fibre compositions.
Figure 9: Impedance v/s Frequency
Hence SSEE has the highest impedance when compared with other composition. It can be inferred that SSEE is the best insulator among the three compositions.
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Manju M B et.al / Materials Today: Proceedings 5 (2018) 3229–3236
Conclusion:
Composites are used in variety of applications and have revolutionized 21st century. E-glass is extensively used as insulators in electrical wiring but its mechanical strength is relatively lower when compared to other fibers. E glass is combined with S-glass fiber in different fashions and its electrical properties are compared with S-glass fiber composite. It is found from the experiments that SSEE composition has the highest insulating properties and S- glass fiber has the least insulating properties. It is also inferred that insulating properties are reduced when composites are fabricated for alternate layers of E glass fibers as compared to the composites that are fabricated for adjacent layers of E-glass fibers. Acknowledgements We take this opportunity to express our deep sense of gratitude to Dr. Murugendrappa M V for his invaluable guidance and also for permitting us to use the required laboratory. We also thank Dr. M Ramachandra and Dr. S Srinivas for permitting us to utilize the abrasive water jet machine facility. References [1] Fabrication And Testing Of Fibre Reinforced Polymer Composites Material by K.Alagarraja, A.Dhamodharan, K.Gopinathan ,R.Mathan Raj , K.Ram Kumar IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) e- ISSN: 2278-1684, p-ISSN : 2320–334X,PP 27-34 [2] Glass fiber-reinforced polymer composites – A review, journal of Reinforced Plastics and Composites July 2014 vol. 33 no. 13 1258-1275 [3] Evaluation of Thermal Properties of E-Glass/ Epoxy Composites Filled By Different Filler Materials by K.Devendra1, T. Rangaswamy (International Journal Of Computational Engineering Research (ijceronline.com) Vol. 2 Issue.5) [4] A review on electrical properties of fiber reinforced polymer composites by D. Pathania and D. Singh (International Journal of Theoretical & Applied Sciences, 1(2): 34-37(2009))
ScienceDirect Materials Today: Proceedings 5 (2018) 3229–3236
www.materialstoday.com/proceedings
ICAMA 2016
Electrical Conductivity Studies of Glass Fiber Reinforced Polymer Composites Manju M Ba, Sai Vignesha, Nikhil K Sa, Sharaj A Pa, Madhav Murthy*a a
BMS College of Engineernig, Bangalore 560019, India
Abstract Polymer matrix composite is a material consisting of a polymer (resin) matrix combined with a fibrous reinforcing dispersed phase. Polymer Matrix Composites are very popular due to their low cost and simple fabrication methods. Use of non-reinforced polymers as structure materials is limited by low level of their mechanical properties: tensile strength of one of the strongest polymers - epoxy resin is 20000 psi (140 MPa). In addition to relatively low strength, polymer materials possess low impact resistance. Two main kinds of polymers are thermosets and thermoplastics. Thermosets have qualities such as a well-bonded three-dimensional molecular structure after curing. They decompose instead of melting on hardening. Merely changing the basic composition of the resin is enough to alter the conditions suitably for curing and determine its other characteristics. They can be retained in a partially cured condition too over prolonged periods of time, rendering Thermosets very flexible. Thus, they are the most suited as matrix bases for advanced conditions fiber reinforced composites. Thermosets find wide ranging applications in the chopped fiber composites form particularly when a premixed or molding compound with fibers of specific quality and aspect ratio happens to be starting material as in epoxy, polymer and phenolic polyamide resins. Thermoplastics have one- or twodimensional molecular structure and they tend to at an elevated temperature and show exaggerated melting point. Another advantage is that the process of softening at elevated temperatures can reversed to regain its properties during cooling, facilitating applications of conventional compress techniques to mold the compounds.
© 2018 Elsevier Ltd. All rights reserved. Selection and Peer-review under responsibility of International Conference on Advanced Materials and Applications (ICAMA 2016). Keywords: FRP Composites; Electrical conductivity; Insulating properties; S-Glass fibers; E-Glass fibers.
1. Introduction: Composite materials produce a combination of properties of two or more materials that cannot be achieved by either fiber or matrix when they are acting alone[1]. * Corresponding author. Tel. 9482852100
E-mail address: [email protected] 2214-7853 © 2018 Elsevier Ltd. All rights reserved. Selection and Peer-review under responsibility of International Conference on Advanced Materials and Applications (ICAMA 2016).
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Manju M B et.al / Materials Today: Proceedings 5 (2018) 3229–3236
Physical and chemical properties of the constituent materials differ significantly. Composites are most often used because of their light weight, reduction of higher fatigue resistance. Composites consist of two main constituents: a.
Matrix: The matrix is basically a homogeneous and monolithic material in which a fiber system of a composite is embedded. It is completely continuous. The matrix provides a medium for binding and holding reinforcements together into a solid. It offers protection to the reinforcements from environmental damage, serves to transfer load, and provides finish, texture, color, durability and functionality.
b. Reinforcements: Reinforcement is basically the discontinuous or dispersed phase of the composites. It is responsible for composites high strength and stiffness. The most important reinforced fibers in current use are glass, graphite, carbon and Kevlar. Composite materials are usually classified by the type of reinforcement and the type of matrix they use. Glass fiberreinforced polymer (GFRP) composites are the most commonly used composite materials. The mechanical behavior of an FRP composite basically depends on the fiber strength, matrix strength and the interface bonding to enable stress transfer. Suitable compositions and orientation of fibers help in achieving desired properties and functional characteristics of GFRP composites that are equal to steel, higher stiffness than aluminum and a specific gravity equal to one-quarter of steel. The properties of composites depend on the fibers laid or laminated in the matrix during the composite preparation[2]. The various GF reinforcements in the composites have been produced to enhance the mechanical properties of the composites. GF reinforced composite materials have very good environmental resistance, higher damage tolerance for impact loading, high specific strength and stiffness. Epoxy resins are widely used because they have high chemical/corrosion resistant properties and low shrinkage on curing. Several factors influence the energy dissipation of FRP composites such as fiber volume, fiber orientation, matrix material, temperature, moisture and other properties like thickness of lamina and thickness of the composites. All FRP composites have temperature-dependent mechanical properties. E-Glass or electrical grade glass was developed for standoff insulators for electrical wiring. E-Glass is a low alkali glass with a typical nominal composition of 54% of SiO2, 14% of Al2O3, 22% of CaO + MgO, 10% of B2O3 and less than 2% of Na2O+K2O. Even though E-glass has excellent insulating properties, its mechanical properties are not sufficient in many instances. S-Glass has a nominal composition of 65% of SiO2, 25% of Al2O3, 10% of MgO. Sglass has superior mechanical strength when compared to E-glass but lacks in insulating properties[3]. Hence Sglass is used in applications that require improved mechanical properties compared to E-glass based composites. But there is a compromise in electrical properties [4]. To tackle this problem, this article aims to combine S-glass and Eglass and to evaluate its electrical properties at room temperature. 2.
Methodology:
E glass and S glass fibers were used as reinforcement in the preparation of this hybrid. Epoxy resin LY556 was used as a matrix. To facilitate and speed up the hardening process, hardener HY951 was used. The fibers used for the experiment were bi directional, cross stitched. A wooden board of required dimensions was used as a mold. Acrylic sheet was wrapped around the mold so that the prepared composite does not adhere to the board. Ten parts of LY556 epoxy resin was mixed with one part of HY951 hardener, this mixture was stirred thoroughly to ensure a proper mix. Fibers were cut to the required dimensions using composite shear.The prepared mixture is poured on to an acrylic sheet and spread to obtain an even coat. First layer of the fiber was placed on the matrix coated mold. The fiber is pressed so that the resin mixture (matrix) impregnates it. Then using a roller the resin is evenly spread. More resin is poured and spread evenly and another layer of fiber is placed and the process is repeated until a desired configuration is obtained. This process can also be done for required thickness.
Manju M B et.al/ Materials Today: Proceedings 5 (2018) 3229–3236
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Three different glass fiber configurations were selected for the experimental purpose. They are: a) S Glass Fiber Composite b) S-E-S-E Hybrid Glass Fiber Composite c) S-S-E-E Hybrid Glass Fiber Composite. The prepared composites are allowed to dry for about 8-10 hours. The dried composites are cut into pellets of 2cm diameter using Abrasive water jet machine by a suitable coordinate input data. The pellets are silver coated on both the sides since the material is non-conductive. Electrical properties at room temperature are experimentally found using an impedance analyzer. The 6500B series of precision impedance analyzer provides impedance measurement capability from 20Hz to 5MHz. This range of functions enables us to accurately characterize a component over a wide range of frequencies. The instrument can be used in 2 modes, graphical and meter. The GUI enables measurement parameters to be easily modified. Properties such as admittance, inductance, capacitance, conductance and impedance are calculated for various frequencies ranging from 102 – 105.
Figure 1: Wayne Kerr 6500B Precision Impedance Analyzer (Reference: 8)
3. Results and discussion: The variation of the above mentioned properties against frequency, for the above mentioned materials, have been drawn and analyzed. Here the Frequency (x-axis) is taken in logarithmic scale. a.
Capacitance and Dielectric Constant:
Dielectric Constant is used to determine the ability of an insulator to store electrical energy. It is the ratio of capacitance of a capacitor with test material as the dielectric to the capacitance of a capacitor with a vacuum as the dielectric. For materials that are to be used to insulate electrical components the dielectric constant should be low. For materials that are to be used as a dielectric in a capacitor, the dielectric constant should be high so that the capacitor dimensions can be minimized. Capacitance is the ability of a body to store an electrical charge. It is also the ratio of the change in an electric charge in a system to the corresponding change in its electric potential. A material with a large capacitance holds more electric charge at a given voltage, than one with low capacitance.
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Manju M B et.al / Materials Today: Proceedings 5 (2018) 3229–3236
As the frequency increases, the capacitance and dielectric constant for all three compositions, unsteady at first, remains constant after a certain frequency which can be called as threshold frequency. From the graph, it can be observed that after the threshold frequency, SSEE composition has the least dielectric constant and S - glass has the highest dielectric constant and capacitance for a particular frequency. Hence it can be inferred that SSEE composite is the best insulator out of the three compositions.
Figure 2: Capacitance v/s Frequency
Figure 3: Dielectric Constant v/s Frequency
Manju M B et.al/ Materials Today: Proceedings 5 (2018) 3229–3236
b. Admittance, Conductance and Susceptance:
Figure 4: Admittance v/s Frequency
Figure 5: Conductance v/s Frequency
Figure 6: Susceptance v/s Frequency
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Manju M B et.al / Materials Today: Proceedings 5 (2018) 3229–3236
Admittance is an expression of the ease with which alternating current flows through a system or substance. Admittance is a vector quantity which comprises of two independent scalar phenomena: conductance and susceptance. Conductance is a measure of the ease with which charge carriers can pass through a substance. Conductance is observed with both Alternating current and direct current. Susceptance is an expression of the readiness with which a system or substance releases stored energy as the current and voltage fluctuate. It is observed only for AC. When AC passes through a component that contains susceptance, energy might be stored and released in the form of a magnetic field, in which case the susceptance is inductive, or energy might be stored and released in the form of an electric field, in which case the susceptance is capacitive. As the frequency increases, Admittance, conductance and susceptance remains constant for all the three compositions and after a threshold value is crossed it rises exponentially with S Glass fiber composition having the highest slope and SSEE hybrid glass fiber composition having the least slope. Hence S-glass fiber has the higher admittance when compared to other two compositions. From this it can be inferred that addition of E glass reduces admittance, conductance and susceptance. c.
Impedance, Reactance and Resistance:
Resistance is a force that tends to resist the flow of electrical current. The more resistive a resistor is the more it restricts the flow of electricity through it. Resistance needs to be considered irrespective of whether DC or AC flowing through the circuit. Reactance comes into existence only when AC is flowing through a circuit. It is the inertia developed against the motion of electrons due to the flow of AC. There are two types of reactance: Capacitative reactance and inductive reactance. Impedance is actually the overall opposition to current presented by the circuit. Impedance of a circuit is the square root of the sum of the squares of the resistance and reactance. As the frequency increases, for all the three compositions, resistance of the materials decreases and becomes constant after a threshold value has been crossed. Here SSEE hybrid glass fibre composition has the highest slope and SESE hybrid glass fibre composition has the least slope meaning to say SESE hybrid glass fibre composition retains its resistance the longest among the taken three glass fibre compositions.
Figure 7: Resistance v/s Frequency
Manju M B et.al/ Materials Today: Proceedings 5 (2018) 3229–3236
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Reactance is negative for all the three compositions. As the frequency increases, impedance of the materials increases and after a threshold value has been crossed it becomes constant. Here S Glass fiber composition has the highest slope and SSEE hybrid glass fiber composition has the least.
Figure 8: Reactance v/s Frequency
As the frequency increases, impedance of the materials decreases and becomes constant after a threshold value has been crossed. Here SSEE hybrid glass fibre composition has the highest slope and S Glass fibre composition has the least slope meaning to say S Glass fibre composition retains its impedance the longest among the taken three glass fibre compositions.
Figure 9: Impedance v/s Frequency
Hence SSEE has the highest impedance when compared with other composition. It can be inferred that SSEE is the best insulator among the three compositions.
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4.
Manju M B et.al / Materials Today: Proceedings 5 (2018) 3229–3236
Conclusion:
Composites are used in variety of applications and have revolutionized 21st century. E-glass is extensively used as insulators in electrical wiring but its mechanical strength is relatively lower when compared to other fibers. E glass is combined with S-glass fiber in different fashions and its electrical properties are compared with S-glass fiber composite. It is found from the experiments that SSEE composition has the highest insulating properties and S- glass fiber has the least insulating properties. It is also inferred that insulating properties are reduced when composites are fabricated for alternate layers of E glass fibers as compared to the composites that are fabricated for adjacent layers of E-glass fibers. Acknowledgements We take this opportunity to express our deep sense of gratitude to Dr. Murugendrappa M V for his invaluable guidance and also for permitting us to use the required laboratory. We also thank Dr. M Ramachandra and Dr. S Srinivas for permitting us to utilize the abrasive water jet machine facility. References [1] Fabrication And Testing Of Fibre Reinforced Polymer Composites Material by K.Alagarraja, A.Dhamodharan, K.Gopinathan ,R.Mathan Raj , K.Ram Kumar IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) e- ISSN: 2278-1684, p-ISSN : 2320–334X,PP 27-34 [2] Glass fiber-reinforced polymer composites – A review, journal of Reinforced Plastics and Composites July 2014 vol. 33 no. 13 1258-1275 [3] Evaluation of Thermal Properties of E-Glass/ Epoxy Composites Filled By Different Filler Materials by K.Devendra1, T. Rangaswamy (International Journal Of Computational Engineering Research (ijceronline.com) Vol. 2 Issue.5) [4] A review on electrical properties of fiber reinforced polymer composites by D. Pathania and D. Singh (International Journal of Theoretical & Applied Sciences, 1(2): 34-37(2009))