Experimental Investigation and Analysis of Ecofriendly Compression Molded Woven Plant Fibre Polyester Composite

Abstract

Polymer matrix composites are widely applied for the manufacturing of components employed in hostile environments to increase the service life and sometimes at a later stage for the reclamation of worn out parts. Every decade, numerous materials and techniques are being introduced and developed for the effective protection of low cost bulk materials out of which the fabrication of components could be done. Among such techniques hand layup, matched die mould methods, contact mould methods, filament winding and pultrusion methods has being employed increasingly in the process industries which has several significant advantages over other processes. It has become a process of its reliability, better process control, ease of use, good surface finish and closeness of dimensions. One among the method matched die mould method was selected as the process of preparation of the composite plate in the presented work. However, there are some inherent problems with control of resin flow, application of high temperature for curing during fabrication process. To address those main problems, a systematic investigation was carried out. The selected material is natural plant fibre available in abundant called “Crotalaria juncea” and is being employed as a green manuring plant in agriculture. In the investigation, the fibre is taken in two different forms of random and woven orientations and plate fabrication is done with unsaturated polyester resin as the matrix. The investigation is on woven orientation of biaxial, biaxially stitched and unidirectional woven types were done using the fibre to the size of the plate to be fabricated. Woven fibres of these three types were done at fibre design centre, Kerala. It was found that the fabrication could be done by placing two layer and three layer of the woven mat alone. So for the three woven types, two layer and three layer plates were fabricated to give about six plates in total. Here again to arrive at a closeness value for each combination, three plates were fabricated and the average value is got by testing. Tensile, flexural, impact and shear testing was done on all the plates as per ASTM standards and the responses were noted and plots were drawn and studied for the orientation for which the material possessed best property. The second part of the study was, with the experimental results got from the woven orientation, analysis was done by ANSYS and LS-DYNA software for the mechanical property and the responses got, was matching with the experimental testing methods and found that both the results were nearly the same thereby optimizing the results achieved. This is presented in detail in the forth coming chapters. The studies revealed that the fibre parameters taken had a significant influence on the mechanical properties. It was found that at a particular weight fraction the mechanical properties achieved the highest values in case of random orientation and particular woven orientations in case woven types. The increase in layers also had an influence over the property of the material. This composite prepared also initiates us in preparing newer composites with existing natural fibers, which haven’t been yet explored and which can reduce the cost. This gives way also in preparation of the same and releasing a newer variety of material to the Engineering industry which can be suited for some required application.