Manufacturing Science and Technology 5(2): 17-21, 2018 http://www.hrpub.org DOI: 10.13189/mst.2018.050201 Evaluation of Mechanical Properties of Wood Particles Reinforced Polymer Composites H. V. Divya 1,* , H. M. Kavya 2 , D. Saravana Bavan 2 , B. Yogesha 1 1 Malnad College of Engineering, Hassan, Visvesvaraya Technological University, Belagavi, Karnataka, India 2 Dayananda Sagar University, India Copyright©2018 by authors, all rights reserved. Authors agree that this article remains permanently open access under the terms of the Creative Commons Attribution License 4.0 International License Abstract Natural fiber composites are more attractive due to their high specific strength and lightweight. The focus in this work has been to study the influence of wood fibres on the mechanical properties of the polymer composites manufactured by extrusion and injection moulding process. Tensile and flexural tests were conducted to evaluate the tensile and flexural properties of the compounded composites. The interfacial properties, internal cracks are evaluated by using Scanning Electron Microscope. The results indicate flexural strength of the wood plastic composites increases with decrease in wood particles content. The tensile strength of pure plastic blend is higher compared to wood plastic composites. Keywords Polypropylene, High Density Polyethylene, Injection Moulding, Mechanical Properties 1. Introduction Polymer composites are the class of composite materials for structural applications. Polymer composites are often used as the substitute for the metal based ones in the mechanical industries [1]. They are used in the penal of solar boards, automobile accessories, polymer gears, body of modern cars, sports ratchets etc. [2]. Natural fibre reinforced polymer based composite materials are new class of engineering materials. The development of natural fiber composite materials has been a hot topic recently due to the increasing environmental awareness. Natural fibers are one such proficient material which replaces the synthetic materials and its related products for the light weight and high strength applications. The advantages of natural fiber composites include lightweight, low- energy production, and environmental friendly [3]. The use of natural fibers reduces weight by 10% and lowers the energy needed for production by 80%, while the cost of the component is 5% lower than the comparable fiber glass-reinforced component [4]. Interest in this area is rapidly growing both in terms of their industrial applications and fundamental research as they are renewable, cheap, completely or partially recyclable, and biodegradable [5]. The application of natural fiber reinforced polymer composites and natural-based resins for replacing existing synthetic polymer or glass fiber reinforced materials in huge [6]. In the plastic-based composites, the polymers, thermoplastics, act as a matrix and flour of wood or other natural flour are reinforcement [7]. Wood–plastic composite (WPC) is a very promising and sustainable green material to achieve durability without using toxic chemicals. The term WPCs refers to any composites that contain plant fiber and thermosets or thermoplastics. In comparison to other fibrous materials, plant fibers are in general suitable to reinforce plastics due to relative high strength and stiffness, low cost, low density, low CO2 emission, biodegradability and annually renewable [8]. Nicole M. Stark. et.al, studied that Commercial wood flour, the most common wood-derived filler for thermoplastics, is produced in a mixture of particle sizes and generally has a lower aspect ratio than wood and other natural fibers. To understand how wood flour and fiber characteristics influence the mechanical properties of polypropylene composites, we first investigated the effect of different sizes of wood flour particles on the mechanical properties of wood-flour-filled polypropylene composites [9]. Qiangyuan.et.al, studied the properties of wood plastic composite (WPC). WPC with high modulus and impact strength were manufactured by combining polyethylene (PE) or polypropylene (PP) with wood fiber (WF) using twin-screw extruder techniques. The advantage of using low melt viscosity polymer matrices is that it enhances the modulus and reduces the overall viscosity of the system. SEM analysis of the composites indicates that the polymer molecules penetrate into the vessels and cracks of the cellulose fiber, which decreases the number of voids and produces a higher