Studies on Fracture Performance of Bio-fiber-Silica-glass Fiber Reinforced Epoxy Hybrid Composites
Arun Kumar Chaudhary1, Prakash Chandra Gope2, Vinay Kumar Singh2 1 Assistant Professor 1 Department of Production Engineering 2 Department of Mechanical Engineering College of Technology, G. B. Pant University of Agriculture & Technology, Pantnagar-263145 Udham Singh Nagar, Uttarakhand , India * E mail:
[email protected],
[email protected] ABSTRACT In the present investigation, fibers from banana stem and Bagasse are used in addition to low wt% of silica to cast bio composites. Extraction of the banana fibers, Bagasse fibers and preparation of both banana and Bagasse fibers were carried out as explained elsewhere in literature. The lengths of the fibers are kept between 180 to 425 micrometer. Composites, containing lower fiber content of Bagasse and banana (10 wt %) and higher fiber content (20 wt %) were used with silica (2 wt%) and mixed with epoxy CY 230 epoxy resin. Different mechanical properties such as tensile, compressive, impact, flexural, fracture strength etc are discussed and characterized. Introduction With growing environmental awareness, ecological concerns and new legislations, bio-fiber-reinforced plastic composites have received increasing attention during the recent decades. The composites have many advantages over traditional glass fiber or inorganic mineral-filled materials, including lower cost, lighter weight, environmental friendliness, and recyclability. In addition, use of their composites have established comparable performance with those of glass fiber composites with possibility for their use as structural components as well [1-3]. When such materials are used in composites, developing countries, which produce these, become part of global composite industry as developer and manufacturer leading to increased revenues and creation of jobs [4]. In view of the above, many attempts have been made to characterize the lignocellulosic fibers either individually [5-6], or as part of their composites research [7]. Sugarcane is one of the most abundant agro fiber resources whose worldwide annual production of 1200 million metric tones per year. Bagasse (BaG) is a byproduct from sugarcane processing. The composition of bagasse is approximately 50% cellulose, 25% hemicellulose, and 25% lignin [8]. Currently the main use of bagasse is for energy in the sugarcane industry through burning, but their caloric value is relatively low compared to other fuel resources [9]. Banana fiber (BaN) is extracted from the waste product of banana cultivation. Due to high cellulose content and comparatively low microfibrillar angle, it has superior mechanical properties, especially tensile strength and modulus [1013]. It is thus considered as a promising candidate for replacing conventional glass fibers in the fiber-reinforced composites. Earlier studies showed that BaN provided good reinforcement for various thermosetting resins such as unsaturated polyester [14-18], phenol formaldehyde (PF) [19-20], and epoxy [21]. This paper presents mechanical and fracture behavior aspects of two different types of lignocellulosic fibers of India namely, fiber from bark (banana) and fiber from agro waste (sugarcane bagasse). It is hoped that such attempts would lead to the better utilization of these fibers through composite technology leading to a low cost eco friendly composite materials for many automotive parts, household equipments, and also as packing and insulating materials. Experimental Aspects Materials T. Proulx (ed.), Experimental and Applied Mechanics, Volume 6, Conference Proceedings of the Society for Experimental Mechanics Series 9999, DOI 10.1007/978-1-4614-0222-0_44, © The Society for Experimental Mechanics, Inc. 2011
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Two types of fibers, namely banana fibers (Musa sapientum) obtained from the pseudostem of the plant and sugarcane (Saccharum officinarum) bagasse fibers obtained from a nearby sugar mill in the state of Uttarakhand, India were used in this study. Banana fibers were extracted from the pseudostem (average diameter of 150 mm) of the banana plant. The leaf sheaths from the pseudostem were cut in parts of about 300 mm length using long knife and then dried outdoors exposing the fibers to the sun for about two to three weeks. They were then dried in a hot air oven at 650 C until constant mass was observed. They were then further cut in a knife mill to get fibers of 3–5 mm length. The banana fibers were cleaned with 5% sodium hypochlorite before they were maintained at 1000 C for 1 h in an autoclave followed by drying at 650 C for 72 h to maintain constant moisture content. The sugarcane fiber also known as Bagasse fiber (here after called as Bagasse and denoted as BaG) used in the present study are collected from the nearby sugar industry. No fiber preparation was required in this case since the Bagasse fiber received was in the fiber form (not extracted from the stem/stalk as described for banana fiber), except cutting them to random size using a suitable cutter and conditioning them by keeping the fibers for 12 h at 650 C to maintain constant moisture content. The fibers obtained from banana and Bagasse (Fig. 1) were then grinded in ball mill to obtain relatively finer particles. The sizes of the fibers were controlled by using sieves (ASTM 18 and 40). Silica is another reinforcing element used in the present investigation. In the present investigation nano sized silica powder (
