M. Kathiresan

Friction and wear studies of die cast aluminum alloy‐aluminum oxide‐reinforced composites

Purpose – Metal matrix composites (MMCs) are engineered materials formed by the combination of metal matrix and reinforcement materials. They have a stiff and hard reinforcing phase in metallic matrix. The matrix includes metals such as aluminum, magnesium, copper and their alloys. The purpose of this paper is to describe the development of an aluminum alloy‐aluminum oxide composite using a new combination of vortex method and pressure die casting technique and the subsequent tribological studies.Design/methodology/approach – An aluminum alloy‐aluminum oxide composite was developed using vortex method and pressure die casting technique. The aluminum alloy‐1 wt% aluminum oxide was die cast using LM24 aluminum alloy as the matrix material and aluminum oxide particles of average particle size of 16 μm as a reinforcement material. The friction and wear characteristics of the composite were assessed using a pin‐on‐disc set‐up; the test specimen, 8‐mm diameter cylindrical specimens of the composite, was mated a...

Physicochemical properties of new cellulosic Artisdita hystrix leaf fiber

ABSTRACT The characterization of new natural fiber is increasing due to its excellent properties. This drives investigators to create high performance composites. The present investigation was designed to study the physicochemical properties of fibers obtained from the leaf of the Artistida hystrix. The Artistida hystrix fibers (AHFs) had crystallinity index (44.85%), cellulose (59.54 wt%), hemicellulose (11.35 wt%), lignin (8.42 wt%), and density (540 kg m−3). The tensile strength of AHFs was 440 ± 13.4 MPa with an average strain rate of 1.57 ± 0.04%. The calculated microfibril angle of AHFs was 12.64 ± 0.45°, which influenced the mechanical properties.

Characterization of New Natural Cellulosic Fiber from the Bark of Dichrostachys Cinerea

ABSTRACT The increasing environmental awareness has directed attention of the researchers towards the field of natural fiber composites. The aim of this investigation is to understand the physico-chemical properties of fibers extracted from the bark of the Dichrostachys Cinerea (DC) plant. Dichrostachys Cinerea fibers (DCFs) has cellulose (72.4 wt. %), hemicellulose (13.08 wt. %), lignin (16.89 wt. %), density (1240 kg/m3), crystallinity index (57.82%), and tensile strength (873 ± 14 MPa). Besides the cellulose degradation of DCFs at 359.3° vide by the thermo-gravimetric analysis and chemical groups are identified by Fourier transform analysis. Eventually the characterization results of DCFs strongly show the possibility of reinforcement in polymer matrices.

Characterization of raw and alkali treated new natural cellulosic fiber from Coccinia grandis.L

The physical, chemical, tensile, crystalline, thermal, and surface morphological properties of raw and alkali treated Coccinia Grandis.L Fibers (CGFs) were characterized for the first time in this work. The results of the chemical analysis indicate that, after alkali treatment, the cellulose content of CGFs increased whereas hemicelluloses, lignin and wax contents decreased. This directly influenced the tensile strength, crystallinity index, thermal stability and the roughness of alkali-treated CGFs. The thermal stability and activation energy of the CGFs improved from 213.4 °C to 220.6 °C and 67.02 kJ/mol to 73.43 kJ/mol, respectively, due to alkali treatment. The statistical approach, Weibull distribution was adopted to analyze the tensile properties. The improved properties of the alkali treated CGF indicate that it could be an appropriate material for reinforcement in polymer composites.

Preparation and characterization of biodegradable sugarcane bagasse nano reinforcement for polymer composites using ball milling operation

ABSTRACT The present work includes the processing and characterization of nano-based natural reinforcement for polymer composite materials. Sugarcane bagasse has been collected and the fibers were extracted using manual striping process. Undesirable materials present in the extracted fibers were removed by 1% NaOH-based chemical treatment. The macrofibers were reduced to nano scale by using high-energy ball milling process. Nanoparticles from bagasse fibers were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The degree of crystallinity of nano bagasse is 55.2% and it was reported by using XRD. A FTIR spectrum confirms the presence of cellulose functional groups in nano bagasse. The nano bagasse dimensions and morphology were investigated using SEM. The average length and diameter of the nano bagasse is 51.2 and 46.1 nm, respectively. Thermal stability of the nano bagasse was revealed by TGA analysis. The chemical composition of cellulose, lignin, and hemicellulose contents was also investigated.

The Hybrid Effect of Jute/Kenaf/E-Glass Woven Fabric Epoxy Composites for Medium Load Applications: Impact, Inter-Laminar Strength, and Failure Surface Characterization

ABSTRACT This research has been carried out to find better hybrid natural/glass fiber-reinforced composites for engineering applications. This research work studied the impact and inter-laminar strength of E-glass with jute/kenaf woven fabric epoxy composites with the aim of evaluating the hybridization effects on different laminate stacking sequences made with jute, kenaf, and E-glass fabrics by the vacuum bagging method. All the laminates were prepared in 300 × 300 mm2 with a total of five plies maintained at 3 mm thickness, by varying the number and position of jute, kenaf, glass layers so as to obtain nine different stacking sequences. Among them, one group of all pure jute, pure kenaf, and pure E-glass laminates were also fabricated for comparison purpose. The specimen preparation and testing were carried out as per ASTM standards. From the results, it is shown that the properties of jute/kenaf fabrics-reinforced epoxy composites can be enhanced by hybridization with the addition of glass fabrics. The hybridization of jute/kenaf fabrics with E-glass fabrics provides a method to improve the mechanical impact and inter-laminar strength over pure natural fiber-reinforced composites. The hybrid laminate having E-glass and kenaf fiber plies as skin layers and jute fiber plies as core layers showed better properties compared to other laminates.

Dry sliding wear studies of die cast aluminium–silicon carbide composites

Abstract Aluminium alloy metal matrix composites (MMCs) have evoked keen interest in recent times for potential applications in aerospace and automotive industries owing to their superior strength to weight ratio and high temperature strength. In the present work, aluminium alloy–silicon carbide composite is developed using a new combination of vortex method and pressure die casting technique. The dry sliding wear properties on aluminium alloy–silicon carbide MMC are carried out using a pin-on-disc wear testing apparatus at room temperature. The effects of normal load and sliding speed on tribological properties of the MMC pin on sliding with En 36 steel disc are evaluated. The wear rate increases with normal load and sliding speed. The specific wear rate marginally decreases with normal load. The coefficient of friction decreases with normal load and sliding speed. The wear and friction coefficient of the aluminium alloy–silicon carbide MMC is lower than that of the plain aluminium alloy.

Effect of Various Chemical Treatments of Prosopis juliflora Fibers as Composite Reinforcement: Physicochemical, Thermal, Mechanical, and Morphological Properties

ABSTRACT The present environmental regulations enforced by the government authorities have made the investigators around the globe to make use of more and more green materials particularly in composite systems. In this context, natural fibers play an important role and proven to be excellent reinforcements in polymer matrices. However, these natural fibers have got one major limitation: their incompatible hydrophilic behavior which affects their bonding with hydrophobic matrixes. Researchers over the years have come up with several fiber surface modification processes to overcome this defect. So, in this present study, the effect of various chemical treatments like alkaline, benzoyl peroxide, potassium permanganate, and stearic acid on Prosopis juliflora fibers has been discussed. These various chemical treatments on the fiber surfaces impacted on their structure, composition, and properties which were discovered through chemical analysis, Fourier transform-infrared, X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, scanning electron microscopy, and tensile testing.

Preparation of nanofiber particles from the leaf of Aristida hystrix and its characterization

ABSTRACT Natural fibers have been focused by researches to develop high performance and eco-friendly reinforcement in polymer composites. The present work is deliberated on the characterization of nanoparticles of Aristida hystrix (AH) leaf fiber to confirm their compatibility as reinforcement in polymer composites. The macro leaf fiber is reduced to nanofiber particles by ball milling method. From the characterization results, the AH leaf nanoparticles had cellulose content of (61.21 wt %) and crystallinity index (58.37%). The thermal stability of AH nanofiber particles was studied under nitrogen and oxygen environment. From the results obtained, the thermal stability of this fiber was found to be closer to 298.6°C and 312.6°C respectively. The morphological analysis evidenced that the cellulosic particles were in nanoscale. The antibacterial activity of AH nanofiber particles against Escherichia coli, Acetino bacteria, Klebsiella pneumonia, and Staphylococcus aureus was determined by well diffusion method. The extracted AH nanopowder prepared by distilled water showed the maximum zone of inhibition against all tested bacterias in low concentrations (50 mg/50 µL). The zone of inhibition of AH fiber particles was better in Staphylococcus aureus bacteria, which is suitable for the medical applications.