Damping Properties of E-Glass/ Epoxy Composite with LDPE Filler Material

Transcription

1 Damping Properties of E-Glass/ Epoxy Composite with LDPE Filler Material Jeevan M 1, Marwin D cunha1, Nithin D B 1, Sandeep P P 1, Shivaramu HT 2, Dr. Umashankar K S 2 1 PG scholar K V G College of Engineering SULLIA/VTU Belgaum, Karnataka State, India 2 Professor, K V G College of Engineering SULLIA/VTU Belgaum, Karnataka State, India Abstract Low cost, reusable, easily available, good strength materials are the materials that have held the attention of researchers to develop a new product. The present work describes the development and characterization of a new set of polymer composites consisting of bidirectional E- glass fiber as reinforcement, Epoxy Araldite AW106 as matrix and powdered low density polyethene (LDPE) as filler. The newly developed composites are characterized the vibration behaviour. The study of the behavior of composites with addition of filler percentage (0 & 3%) and effect of low density polyethene (LDPE) filler size 600µm on the vibration characteristics are investigated. The composite prepared with addition of filler increases the damping properties of the composites. Keywords E-glass fiber, Epoxy, powdered Low density polyethene (LDPE), Damping propert y I. INTRODUCTION Composite material is a structural material created synthetically or artificially by combining two or more materials having dissimilar characteristics. The composite material contains reinforcing material and matrix material with fillers. Depending on the application the composition of material are changed. The composite products are representative for engineering manufacturers and they are working to get the best composite materials that meet the current requirement of strength and weight reduction [1]. In composites the E-glass fiber reinforced polymer matrix are exhibiting high performance [2]. Epoxy resins were characterized by good thermal and mechanical properties, high chemical and corrosion resistance and when it is processed under variety of conditions there will be low shrinkage on curing. The epoxy resins are widely used for high performance and engineering applications [2]. The use of fillers in the composite has generated much interest due to their low cost, possibility of environment protection and use of locally available renewable resources [3]. It is also observed that mechanical and dimensional stability of sisal- low density polyethene (LDPE) composites could be improved by chemical treatment. There is a considerable improvement in the mechanical properties of low density polyethene (LDPE) based short banana-glass fibers [4]. The melting temperature of low density polyethene (LDPE) is 110ºC [5]. Polymer matrix composites are commonly used in weight sensitive structures due to high stiffness to weight ratio [6]. In designing of composite materials with desired dynamic properties, storage modulus and damping are important features [7]. To find out the theoretical density of composite materials weight fraction method is used [8]. The presence of separate layers in composites may reduce the stiffness and strength of the structures and also may affect some design parameter such as vibration characteristics of the structure [9]. The damping is an important nodal parameter for the design of structure for vibration control. Damping varies with different environmental effects such as frequency, amplitude of stress, temperature and static load [10]. Keeping this in view the present work has been undertaken to develop a polymer composite using E-glass fiber as reinforcement and epoxy resin as matrix with low density polyethene (LDPE) filler. The experimental study is carried out to observe the damping property of composites. II. MATERIALS USED The following are the raw materials used in this work. a. Bidirectional E-glass fiber b. Epoxy resin c. Powdered low density polyethene (LDPE) filler material d. Poly vinyl alcohol (PVA) mold releasing agent. Bidirectional E-glass fiber of 360gsm and Epoxy Araldite AW106, Hardener HV953 are supplied by S&S polymers, Bangalore. The table 2.1 and 2.2 represents the physical properties of E-glass fiber and Epoxy resin/hardner respectively. Table 2.1 Physical properties of Glass fiber 360 gsm GSM Orientation UTS Modulus Density plain-woven fabric 40 Gpa 1.0 Gpa 2.55 g/cc ISSN: Page 298

2 Table 2.2 Resin and hardener properties Properties Units Araldite Hardener AW106 HV953 Commercial Form - Liquid Liquid Viscosity at 25 C mpa.s Density at 25 C g/cm Shelf life - 2years 2years required layers are stacked. After placing the plastic sheet, release gel is spread on the inner surface of the top mould plate which is then kept on the stacked layers and the pressure is applied. The Figure 1,2,3 and 4 represents the Powdered low density polyethene (LDPE) with 600 micron size used as filler material, Die arrangement for compaction using hydraulic press, Bidirectional E- glass fiber with 360gsm, and sample prepared respectively. III. METHODOLOGY The composite material is prepared using Bidirectional Glass Fiber reinforced Epoxy Resin with the addition of powdered low density polyethene (LDPE) filler by adding 0% and 3% weight percentage of low density polyethene (LDPE) Filler. A. Sample preparation According to the volume fractions of fiber, resin and filler materials are taken and by using the mould, samples are prepared. Volume fractions for the different types of samples are tabulated in Table 3.1. Table 3.1 Specimens Prepared Fig 1: Powdered low density polyethene (LDPE) Type 1 2 Fiber 60% 60% Matrix 40% 37% Filler 0% 3% In this study, manual hand layup method is used for preparing composite laminates. In the beginning, release gel is spread on the mould surface to avoid the sticking of epoxy to the surface. Thin plastic sheets are used at the top and bottom of the mould plate to get a good surface finish of the product. Reinforcement in the form of woven roving E-Glass fibers are cut into 250x250 mm size of 16 layers as per the mould size and placed at the surface of mould after thin plastic sheet. Then epoxy resin in liquid form is mixed thoroughly in suitable proportion with a prescribed hardener (curing agent). The sizes of the filler material selected as 600 microns. Also the percentage of filler is varied as: 0%, 3%. The mixed matrix is poured onto the surface of mat already placed in the mould. The epoxy is uniformly spread with the help of the brush. The second layer of mat is then placed on the epoxy surface and a roller is moved with a mild pressure on the mat-epoxy layer to remove any air trapped as well as the excess epoxy present. The process is repeated for each layer of epoxy and mat, till the Fig 2: Die arrangement Fig 3: Bidirectional E-glass fiber ISSN: Page 299

3 B. Measurement setup The experimental setup for vibration measurement is represented in Figure 7. Fig 4: Sample prepared IV. EXPERIMENTATION A.Vibration Amplitude measurement A body is said to vibrate when it describes an oscillating motion about a reference position. The number of times a complete motion cycle takes place during the period of one second is called the Frequency and is measured in hertz (Hz). The following definitions apply to the measurement of mechanical vibration amplitude. Figure 5 represents the terminology used in vibration measurement RMS value a Peak value Amplitude Measurement Peak-peak value RMS Value = X Peak Peak-peak = 2 X Peak Avg Value = Peak Amplitude Avg value Fig 5 Vibration Terminologies. Peak Amplitude (PK) is the maximum excursion of the wave from the zero or equilibrium point. Peak-to-Peak Amplitude (Pk-Pk) is the distance from a negative peak to a positive peak. In the case of the sine wave, the peak-to-peak value is exactly twice the peak value because the waveform is symmetrical. The Figure 3.6 represents damping curve for the vibrating material. t Fig 7: vibration measurement setup An accelerometer is a device for detecting and measuring acceleration. It produces an output, usually electrical, which is proportional to the rate of acceleration. The accelerometer is used to measure and record low frequencies and large dynamic measurement ranges. The accelerometer comprises at least one directional piezoelectric sensing element and an integrated circuit. Each directional piezoelectric sensing element senses inertial forces applied to the accelerometer from a particular direction, X, Y or Z and generates a force voltage signal in response to the inertial forces applied to the accelerometer. The sensitivity of each directional piezoelectric sensing element is in direct proportion to the sensitivity of the integrated circuit and the mass of a first mass. The integrated circuit system receives the force voltage signal from each directional piezoelectric sensing element and generates an output signal for each direction The accelerometer shown in Figure 3.8 is fixing on the rotary setup column and it senses the vibration signals and these sensed signals are acquired in LabVIEW program through USB interface. The NI USB-9229/9239 consists of two components they are NI 9233 module and an NI USB-9162 carrier, as shown in Figure 3.9. Fig 8 Accelerometer Fig 6 Vibration signature ISSN: Page 300

4 % 0% Fig 9 USB DAQ Module C. Data Acquisition To measure signals and transfer the data into a computer is by using a Data Acquisition (DAQ) board. A typical DAQ card or module allows input of analog signals through an Analog to Digital Converter (ADC) and output of analog signals through a DAQ. In addition a DAQ card may facilitate input and output of digital signals. The vibration signals of the rotary setup under different conditions are measured by using accelerometer and LabVIEW program. V. RESULTS AND DISCUSSIONS The investigation of vibration characteristics are carried out for the different sizes of composite material of 0% and 3% of matrix variations. The calculation of specimen is identified for 50mm, 100mm, 150mm, and 200mm length of material. The Figure 11 shows the specimen used for damping measurement. Fig.10: Test specimen The experimental result of damping ratio of the composite material is carried by free vibration test. The damping ratio is calculated using logarithmic decement curve and the Figure 12 represents the damping ration for varying length and varying percentage of reinforcement. Fig 11: Damping ratio of prepared specimens It is observed that the damping ration increases with the increase in the percentage of low density polyethene (LDPE) filler material. It is an indication that LDPE can be used as damping material for structural applications. Energy absorption by structural damping is of considerable importance in that one can damp vibrations in mechanical systems. In this, the viscoelasticity property of LDPE contributes to the increase in the damping properties in the composite material. Defects such as dislocations, phase boundaries, grain boundaries and various interfaces also contribute to damping [11], since defects may move slightly and surfaces may slip slightly with respect to one another during vibration, thereby dissipating energy. VI. CONCLUSIONS The present work is carried out by utilizing the products of plastic as waste management system. The non-degradable plastics are harmful to environment and living organisms. Thus by adopting these waste plastics are made into composite material. It is also observed that damping properties of composite material are changed in the variation of filler materials and these composite materials can be used in the engineering applications where structural damping is required. REFERENCES [1] SushilB.Chopade, Prof.K.M.Narkar, Pratik K Satav, Design and Analysis of E-Glass/Epoxy Composite Monoleaf Spring for Light Vehicle.International Journal of Innovative Research in Science, Engineering and Technology, Vol. 4, Issue 1, January 2015, Page no.1-8 [2] K. Devendra1, T. Rangaswamy, Strength Characterization of E-glass Fiber Reinforced Epoxy Composites with Filler Materials. Journal of Minerals and Materials Characterization and Engineering, 2013, 1, Published Online November 2013, Page no.1-5. [3] Maneesh Tewari1, V. K. Singh, P. Evaluation of Mechanical Properties of Bagasse-Glass Fiber Reinforced Composite.J. Mater. Environ. Sci. 3 (1) (2012) Tewari et al., ISSN : , DEN: JMESCN, Page no.1-14 [4] Sanjaya kumar behera Study on mechanical behavior of polymer based composites with and without wood dust filler.page no.1-41 ISSN: Page 301

5 [5] Marino Xanthos Functional Fillers for Plastics: Second, updated and enlarged edition.wiley-vch Verlag GmbH & Co. KGaA, Weinheim ISBN: Page no.1-18 [6] Mehmet C OLAKO GLU, Damping and Vibration Analysis of Polyethylene Fiber Composite under Varied Temperature J. Mater. Environ. Sci. 3 (1) (2012) Tewari et al. ISSN : , CODEN: JMESCN, Page no [7] Xu Lei1,, Wang Rui, Liu Yong, and Li Jin, The Effect of Woven Structures on the Vibration Characteristics of Glass Fabric/Epoxy Composite Plates.Defence Science Journal, Vol. 61, No. 5, September 2011, page no [8] Ramesh Chandra Mohapatra, Investigations on tensile and flexural strength of wood dust and glass fibre filled epoxy hybrid composites. International journal of mechanical engineering And technology (ijmet) Issn (print),issn (online),volume 4, issue 4, july - august (2013), pp , Page no.1-8 [9] Shishir Kr. Sahu,Jayaram Mohanty, Bankim C. Ray, Indira P. Bhanja and Pravat Kr Modal analysis of delaminated woven fiber composite plates.page no. 1-2 [10] Mehmet C OLAKO GLU, Damping and Vibration Analysis of Polyethylene Fiber Composite under Varied Temperature, J. Mater. Environ. Sci. 3 (1) (2012) Tewari et al. ISSN : CODEN: JMESCN, Page no [11] N. Ganeriwala, in: Proceedings of SPIE The International Socie ty for Optical Engineering, Smart Structures and Materials, 1995: Passive Damping, San Diego, 1995, (Society of Photo-Optical Instrumentation Engineers, Bellingham, 1995) Vol. 2445, p ISSN: Page 302