G. Raghavendra

Jute fiber reinforced epoxy composites and comparison with the glass and neat epoxy composites

The aim of this paper is to replace the traditional fiber composites with a natural-fiber composite in perception of tribological and mechanical accepts. A systematic study has been carried out to investigate jute fiber properties when incorporated into epoxy matrix. Thermogravimetric analysis has also been carried out for jute and epoxy for thermal property analysis. For a comparison purpose epoxy and glass fiber composites are prepared. The investigation reveals that, due to incorporation of jute into polymer epoxy shows better properties than the resins alone; but the properties are inferior to those of glass reinforced in terms of mechanical. When considering the tribological application, the jute fiber shows superior properties than neat and glass-reinforced epoxy composites. The worn out samples were studied using scanning electron microscope.

Evaluation of mechanical and tribological properties of bamboo–glass hybrid fiber reinforced polymer composite

Effect of stacking sequence of mechanical and tribological properties woven bamboo–glass fabric reinforced polymer hybrid composites has been investigated experimentally. Laminate samples were fabricated by hand layup technique in a mold and cured under light pressure at room temperature for 48 h. All the laminates were made with a total of four plies, by varying the number and position of glass layers so as to obtain five different stacking sequences. One group of all bamboo laminate was also fabricated for comparison purpose. Specimen preparation and testing were carried out as per ASTM standards. The results indicated that the properties of bamboo composite can be significantly improved by incorporation of glass fiber in polymer composite. The layer sequence has greater effect on mechanical and tribological properties of hybrid composite.

Effect of Filler Loading on Mechanical and Tribological Properties of Wood Apple Shell Reinforced Epoxy Composite

During the last century, natural fibers and particulates are used as reinforcement in polymer composite that has been continuously growing in the composite industry. This polymer matrix composite has wide range of applications in hostile environment where they are exposed to external attacks such as solid particle erosion. Also, the mechanical properties of different polymer composites show the best alternate to replace the metal material. In the present investigation, an attempt has been made to improve the mechanical and tribological behaviour of polymer matrix composite using wood apple shell particles as a filler material in polymer matrix. Also the temperature variation of the dynamic-mechanical parameters of epoxy matrix composites incorporated with 5, 10, 15, and 20 wt% of wood apple shell particles was investigated by DMA test. It is clearly observed that the incorporation of wood apple shell particles tends to increase the tensile strength, flexural strength, erosive wear resistance, and viscoelastic stiffness of the polymer composite. To validate the results, SEM of the polymer matrix composite has been studied.

Influence of micro/nanofiller alumina on the mechanical behavior of novel hybrid epoxy nanocomposites

In this work, the influence of micro/nanoalumina (Al2O3) on the mechanical properties of epoxy/jute fiber (J)/glass fiber (G) laminates was studied. All the composites are fabricated by the hand layup technique. The flexural strength and tensile strength of the epoxy/hybrid laminates were increased profoundly in the presence of micro/nano-Al2O3. The epoxy + GJGJ + 4 wt% nano-Al2O3 composites showed better flexural results when compared with the epoxy/glass fiber composites, whereas epoxy + GJJG + 4 wt% nano-Al2O3 composites show better tensile results. It was also found that nanofiller-added composites show better results when compared with and without microfiller-added composites. The morphology of the surfaces was examined by scanning electron microscopy to have better insight into the flexural and tensile mechanism.

A novel approach to utilize waste carbon as reinforcement in thermoset composite

Carbon black is produced from waste wood apple shell (WAS) material using pyrolysis at various carbonization temperatures (400 ℃ and 600 ℃) and used as reinforcement in thermoset polymer composite. The composites were prepared at 5, 10, 15, and 20 wt% filler loadings. The characterization of shell particles has been done through proximate, ultimate, and energy dispersive spectroscopy analyses. Tensile, flexural, and hardness tests were performed at different filler loadings. The results indicated that the strength of the polymer composite increased as filler loading increased to some extent and hardness property of the carbon black composite gives better result as compared to neat polymer composite. However, the filler–matrix bonding from tensile and flexural load was analyzed by scanning electron microscopy.

Evaluation of mechanical behaviour of nanometer and micrometer fly ash particle-filled woven bidirectional jute/glass hybrid nanocomposites

The flexural and tensile properties of micrometer and nanometer fly ash particle-filled jute/glass hybrid epoxy composites were studied and compared with the conventional fibers (glass) composites. The effects of nanofiller (2, 4 and 6 wt%) and microfiller (5, 10 and 15 wt%) are also examined. The effects of micro/nanofiller addition in the pure jute fiber and hybrid (glass/jute) composites were investigated with scanning electron microscope. The experimental result shows that due to micro- and nanofiller addition, the strength of all composites is increased. The tensile strength of 4 wt% fly ash nano-filler GJJG (glass-jute-jute-glass) hybrid composites shows better result among other composites and it gives 5% better strength of the glass fiber composites. Whereas 4 wt% fly ash nano-filler GJGJ hybrid composites shows better flexural strength as compared to glass fiber composites.

Moisture Absorption Behavior of Treated and Untreated Eggshell Particulate Epoxy Composites

Weight gain and thickness swelling in bio-waste composites material leads to an adverse effect on properties. In the present investigation the effect of different environments (saline, mineral, kerosene, subzero temperature) on the physical properties of the composites which are fabricated with unboiled(untreated) and boiled(treated 200 °C) eggshell filler materials are studied. XRD, SEM and ultimate analysis of the unboiled and boiled eggshells are also studied. The composites of different weight percentage 4, 8 and 12 wt% of unboiled and boiled eggshell filler epoxy composites are fabricated by a hand lay-up technique. The 12 wt% of boiled eggshell particulates reinforced epoxy composites showed the highest weight gains when exposed to different environments. Least absorption rate observed was for 4 wt% eggshell filler composite in subzero temperature condition. The composites showed a peculiar environmental behavior when exposed to kerosene.

Effects of Environmental Conditions on Erosion Wear of Eggshell Particulate Epoxy Composites

The erosion wear behaviors of unboiled (UB) and boiled eggshells filler reinforced epoxy composites have been characterized. The eggshells epoxy composites have been fabricated using a hand layup technique and the samples have been exposed to different environmental conditions i.e. dry, saline, mineral, kerosene and subzero temperature. To examine the effect of the above mentioned environmental conditions at different impingement angles (30, 45, 60, and 90∘) three different particle velocities (v = 86 m/s, 101 m/s and 119 m/s) were selected for the erosion wear behavior. The highest erosion rate is found at 60∘ impingement angle, which indicates the semi-brittle erosion nature of eggshells epoxy composites. The impingement angle and impact velocity have a notable influence on erosion rate. A fruitful effect of filler addition is observed on the erosion wear rate of composites. The erosion rates of unboiled and boiled eggshells epoxy are compared. The 4 wt% unboiled eggshells filler content shows the highest wear resistance in dry condition. The exposure of composites in different environmental conditions had a negative effect on erosion rate.

Influence of Distinct Environment on the Mechanical Characteristics of Arhar Fiber Polymer Composites

Over the past decades the need for eco-friendly, non-toxic and biodegradable material is growing significantly. Natural fiber polymer composites have become the prior choice for many applications, as the natural fiber polymer composites are economical and eco-friendly materials in contrast with synthetic fiber reinforced composites. In the current study arhar fiber is used as a reinforcing material. Arhar fiber epoxy composites are fabricated using the hand lay-up technique. The materials were tested for weight gain in different environments (saline water, mineral water and subzero temperature condition). The composite samples immersed in the different environments were tested for tensile strength. It is observed that weight gain is more in mineral water and saline water, minimum weight gain is observed in subzero condition. Maximum tensile strength is observed in 10%fiber content samples. Strength depreciation ismore in samples immersed in the saline water environment.

Characterization of Wood Apple Shell Particles

Characterization of bio waste fiber/particulates for the fabrication of bio composite is essential, because the performance of composite depends upon several factors, including chemical composition, physical properties, and environmental condition of fiber/particulates. In this research, a new bio waste lignocellulosic wood apple shell particles have been chosen and characterized their properties through various analyses such as proximate, Brunauer–Emmett–Teller (BET), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD), whether it is a suitable reinforcement for fabrication of polymer composite. From the analysis, it is concluded that the lignin percentage is more which helps to increase the carbon percentage in the shell particles. EDS result shows that wood apple shell contains hard particles which are suitable for the fabrication of polymer composite.