51
The Electromagnetic Wave Absorbing Performance of Low- cost Agricultural Waste/Epoxy-3D Printed Honeycomb Structure at Higher Gigahertz Frequency Range
Muadzam Fahmy Mokhtar1, Raudhahtul Insyirah Miswan1 and Fadzidah Mohd Idris1
1Kolej GENIUS Insan, Universiti Sains Islam Malaysia, Bandar Baru Nilai, Nilai, Malaysia Email: [email protected]
Abstract. The rapid technological advancements in the development of smart devices in this information technology (IT) era produces more harmful electromagnetic pollution due to the electromagnetic interference. The important and main characteristics needed for an electromagnetic absorbing material are lightweight, low cost, thin thickness, high absorption ability and flexible. Therefore, in this research we proposed to fabricate an electromagnetic wave absorbing materials that can absorb the unwanted signals by using agricultural waste (rice husk and burnt rice husk) to be use as filler incorporated into epoxy as polymer matrix. It was then further poured into 3D-printed honeycomb structure. The samples’ analytical properties and morphological studies are characterised by using X-ray diffraction (XRD) and field emission electron microscope (FESEM) respectively. On the other hand, the electromagnetic properties of the materials will be studied by using Vector Network Analyser (VNA) at gigahertz (GHz) frequency range in order to analyse the performance of agricultural waste (filler) incorporated into epoxy (polymer matrix) as electromagnetic absorbing material. Thus, this research can help to decrease electromagnetic interference pollution and minimise the impact of agricultural waste on the natural environment. It is also potential to be used in various electromagnetic absorbing materials used in many applications.
Keyword: Agricultural waste, electromagnetic wave, absorbing material, honeycomb structure Introduction
During this decade filled with plenty technological advancement, electromagnetic radiation has been increased due to the high demand of electronic devices and other equipments. Electromagnetic wave absorbers has been widely used to minimize electromagnetic radiation reflection from radiation such as electronic devices, aircrafts and ships. Nowadays, researchers are thriving to focus on identifying the most prominent waste material that is suitable to be use as a microwave absorbing material.
Recent research states that carbon materials are good electromagnetic wave absorbent as carbon is the element that can absorb plenty unwanted electromagnetic signals. Rice husk contain high carbon percentage thus suitable to be used as the filler in the electromagnetic wave absorbing material. Rice husk are low-cost and easy to find making various research were conducted in the microwave absorbing material industries. These complications triggered researchers interest in identifying and fabricating electromagnetic absorbing materials that are lightweight, can be utilized at a wide frequency range, have strong absorbing material properties, flexible, thin and low-cost to maximize the quantity of EMI being absorbed. The most effective electromagnetic absorbing material should both reduce undesirable radiation and protect the device from stray external signals.
Material and methods
Preparation of Materials for Filler
52
Rice Husk and Burnt Rice Husk were readymade and were collected by commercial. Then they were powdered using the crushing machine up to 12 minutes each in order to get fine powder size, further incorporated into epoxy matrix.
Diagram 2.1.1: Powdered Rice Husk Diagram 2.1.2: Powdered Burnt Rice Husk Preparation of Polymer Matrix
Epoxy Resin and Hardener were used as matrix and curing agent respectively. Epoxy Resin & Hardener were fixed to ratio 4 : 1 and were mixed in a beaker (4ml : 1ml) and stirred gently in 1 minute.
Preparation of Composite Rice Husk/Epoxy Resin
The powdered Rice Husk and powdered Burnt Rice Husk were then poured into the polymer matrix and mixed well in 5 minutes. The mixture was then incorporated into 1mm 3D printed honeycomb structure and left overnight in room temperature.
Results and discussions
High electromagnetic wave absorption was expected due to the effects of morphology, porous structure and 3D printed honeycomb structure. These may helps in having multiple reflection in the composite sample in order to obtain good electromagnetic wave absorbers.
Conclusions
Rice Husk/Epoxy 3D printed Honeycomb Structure has been successfully fabricated. It is also potential to be use in electromagnetic wave absorbing applications.
Acknowledgement
The authors acknowledge Ministry of Higher Education and Universiti Sains Islam Malaysia for financial support under Fundamental Research Grant Scheme (FRGS/1/2020/STG05/USIM/02/3) and USIM-RACER Grant (PPPI/USIM-RACER_0120/KGI/051000/11920). The authors also express deepest gratitude and pleasure towards Kolej GENIUS Insan for providing the apparatus and equipment used in laboratory.
References
[1] K. Selvakumar, et al., "Extraction of Silica from Burnt Paddy Husk," International Journal of ChemTech Research, vol. 6, pp. 4455-4459, 2014.
[2] J. M. Song, et al., "Studies on microwave absorbers prepared with cast alnico magnets," 2005.
53
[3] L. Zahid, et al., "Development of Pyramidal Microwave Absorber Using Sugar Cane Bagasse (Scb)," Progress In Electromagnetics Research, vol. 137, pp. 687-702, 2013.
[4] Y. Lee, et al., "Experimental the Microwave Absorption of Rice Husk/Ash Mixture," in PIERS Proceedings, 2014.
[5] M. N. Iqbal, et al., "A Study of the Anechoic Performance of Rice Husk-Based, Geometrically Tapered, Hollow Absorbers," International Journal of Antennas and Propagation, vol. 2014, 2014.
[6] Y. S. Lee, et al., "Experimental determination of the performance of rice husk-carbon nanotube composites for absorbing microwave signals in the frequency range of 12.4-18 GHz," Progress In Electromagnetics Research, vol. 140, pp. 795-812, 2013–2014
[7] S. Ozah and N. Bhattacharyya, "Nanosized barium hexaferrite in novolac phenolic resin as microwave absorber for X-band application," Journal of Magnetism and Magnetic Materials, vol. 342, pp. 92-99, 2013.
[8] A. Wadhawan, et al., "Nanoparticle-assisted microwave absorption by single-wall carbon nanotubes," Applied Physics Letters, vol. 83, pp. 2683-2685, 2003.
[9] M.F.B.A.M.H.Nornikman,P.J.Soh,A.A.H. Azremi, F. H. Wee, and A. Hasnain, "Parametric study of pyramidal microwave absorber using rice husk. ," Progress In Electromagnetics Research, vol.
Vol. 104, pp. 145-166, 2010.
[10] V. A. Silva, et al., "Nanostructured composites based on carbon nanotubes and epoxy resin for use as radar absorbing materials," Materials Research, vol. 16, pp. 1299-1308, 2013.
[11] J.-M. Thomassin, et al., "Polymer/carbon based composites as electromagnetic interference (EMI) shielding materials," Materials Science and Engineering: R: Reports, vol. 74, pp. 211-232, 2013.
[12] Y. Xu, et al., "Smart absorbing property of composites with MWCNTs and carbonyl iron as the filler," Journal of Magnetism and Magnetic Materials, vol. 343, pp. 239-244, 2013.
