A comprehensive review of techniques for natural fibers as reinforcement in composites: Preparation, processing and characterization.

The increase in awareness of the damage caused by synthetic materials on the environment has led to the development of eco-friendly materials. The researchers have shown a lot of interest in developing such materials which can replace the synthetic materials. As a result, there is an increase in demand for commercial use of the natural fiber-based composites in recent years for various industrial sectors. Natural fibers are sustainable materials which are easily available in nature and have advantages like low-cost, lightweight, renewability, biodegradability and high specific properties. The sustainability of the natural fiber-based composite materials has led to upsurge its applications in various manufacturing sectors. In this paper, we have reviewed the different sources of natural fibers, their properties, modification of natural fibers, the effect of treatments on natural fibers, etc. We also summarize the major applications of natural fibers and their effective use as reinforcement for polymer composite materials.

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Natural Fibers as Sustainable and Renewable Resource for Development of Eco-friendly Composites: A Comprehensive Review

Renewable and sustainable biobased materials: An assessment on biofibers, biofilms, biopolymers and biocomposites

There has been much effort to provide eco-friendly and biodegradable materials for the next generation of composite products owing to global environmental concerns and increased awareness of renewable green resources. An increase in the use of natural materials in composites has led to a reduction in greenhouse gas emissions and carbon footprint of composites. In addition to the benefits obtained from green materials, there are some challenges in working with them, such as poor compatibility between the reinforcing natural fiber and matrix and the relatively high moisture absorption of natural fibers. Green composites can be a suitable alternative for petroleum-based materials. However, before this can be accomplished, there are a number of issues that need to be addressed, including poor interfacial adhesion between the matrix and natural fibers, moisture absorption, poor fire resistance, low impact strength, and low durability. Several researchers have studied the properties of natural fiber composites. These investigations have resulted in the development of several procedures for modifying natural fibers and resins. To address the increasing demand to use eco-friendly materials in different applications, an up-do-date review on natural fiber and resin types and sources, modification and processing techniques, physical and mechanical behaviors, applications, life-cycle assessment, and other properties of green composites is required to provide a better understanding of the behavior of green composites. This paper presents such a review based on 322 studies published since 1978.

A review of natural fiber composites: properties, modification and processing techniques, characterization, applications

Friction stir welding/processing of metals and alloys: A comprehensive review on microstructural evolution

In the majority of commercial scenarios, supply chain management (SCM) is turning out to be a fundamental focus area. In SCM, a hopeful solution for secured information sharing (IS) is blockchain technology. Nevertheless, it is a bit crucial to maintain security at all levels of blockchain, and therefore private and public-key cryptography is often favored. This study improves the security and privacy of a suggested "blockchain assisted supply chain management (SCM)," in which "Modified Data Sanitization and Data Restoration" is performed with an ideal key generation technique to retain sensitive data in each block. The major challenge that must be overcome to make data transmission security is optimal key selection. Significantly, the proposed hybridized algorithm is used to generate the optimal key in both processes. The proposed hybrid model is known as Whale Updated Butterfly Optimization (WU-BO) and is a conceptual mixture of "Butterfly optimization algorithm (BOA) and Whale Optimization Algorithm (WOA)."Eventually, the examination is performed for verifying the enhancement of the developed model. 

Secured information sharing in supply chain management: Modified data sanitization with optimal key generation via hybrid algorithm

Since last few years, the usage of natural fibres has increased because natural fibre is cheaper and more reliable which involves more societal applications. Natural fibre is considered to be society friendly because it gives only less or no harm to humanity. It is biodegradable and less expensive. In this work, the investigation has been carried out on natural fibre reinforced polymer composites prepared using jute fibre and isophthalic polyester matrix along with a solid lubricant. Then they are well mixed with suitable hardener and accelerator for promoting polymerisation. The composite specimen was prepared with short chopped jute fibres of approximately 10 mm in length by using hand layup process with suitable pressure. The composite specimen was prepared according to ASTM standards. Subsequently drilling operation has been carried out in a CNC vertical machining centre using three different types of drilling tools. Here the different types of tools used are Tungsten Carbide, Cobalt and HSS. The cutting force was measured using the Kistler dynamometer, which is an integral part of the vertical machining centre. It has been observed that different drill tools have different variations in forces, but the force obtained by drilling tungsten carbide tool was understood to offer a better result.

Cutting Force Analysis on Drilling of Natural Fiber Reinforced Polymer Composites Material

The friction stir welding is a solid state welding in which welding takes place at a temperature below the melting point. This welding is also known as green technology welding as no harmful gases are generated, as well as fluxes are not formed. In this process joining of two dissimilar materials can be achieved. Through this welding one can overcome defects like porosity, solidification, cracks etc by selecting suitable wilding parameters. Present work investigates the effect of different tool pin geometries on mechanical properties of friction stir welded AA6061 and AA7075 alloys keeping the process parameters constant. The welding is carried with process parameters 1000rpm, 50mm/min and 5KN as tool rotational speed, welding speed and axial load respectively, and for four different pin geometries: (a) cylindrical pin, (B) triangular pin, (c) square pin and (d) hexagonal pin. The welded samples are characterized by mechanical properties like tensile strength and micro Vickers hardness test. By considering the both properties the hexagonal pin shown better characteristics under optimum process parameters.

Mechanical Properties Evaluation of Friction Stir Welded AA6061-AA7075 Alloys for Different Tool pin Geometries

Over the last decades composite materials, plastics and ceramics have been the dominant emerging materials. The volume and number of applications of composite materials have grown steadily, penetrating and conquering new markets relentlessly. So everybody is concentrating on new materials which will be strong enough, less weight, recyclable with reduced cost. Hence all the researchers are concentrated on the composite materials which have all the above properties. The present work is concentrated on coconut coir fiber and Rice husk reinforced polyester hybrid composites. The composites specimen was fabricated with various weight percentages of natural fibers namely coconut coir (20%, 15%, 10%, and 5%) and Rice husk (15%, 10%, and 5%) combined with CamElect 3321 resin using hand lay-up method. So to obtain new composite materials different proportions of coconut coir and Rice husk is added and the mechanical properties such as Tensile strength, Flexural Strength and Impact test were carried out for the samples cut from the fabricated composites specimen to the dimensions as per ASTM standard. With the increasing percentage of the reinforcements the performance of the material is improving. The tensile strength increases with the increase in coir reinforcement percentage and flexural strength increases with the increasing in percentage of the rice husk and the impact strength of the material gets boost with equal proportional percentage of coconut coir and rice husk reinforcement.

Processing and Evaluation of Mechanical Properties of Coconut Coir and Rice Husk Reinforced Natural Hybrid Composites

SDRAM has more excellent transmission rates than the asynchronous Random-Access Memory (DRAM). To govern the data flow, a memory controller is required. A high-speed memory controller also uses high area/ power consumption in addition to the speed restriction. This requires an optimized memory controller to lower the memory controller's area to work efficiently. This study suggested lowering the memory controller's area by optimizing the controller using bypass registers and optimizing the memory management unit operations. The new generation of remote sensing instruments generates a massive amount of data. The Fast Memory Link Bus, a 64-bit data bus, connects the memory controller and the user module. DDR memory data is sent in a burst manner in both clock edges. The proposed design can be synthesized and verified using simulation results and the performance of the Xilinx 14.4 ISE simulator.

S. Pradeep

Papers

Secured information sharing in supply chain management: Modified data sanitization with optimal key generation via hybrid algorithm

Cutting Force Analysis on Drilling of Natural Fiber Reinforced Polymer Composites Material

Mechanical Properties Evaluation of Friction Stir Welded AA6061-AA7075 Alloys for Different Tool pin Geometries

Processing and Evaluation of Mechanical Properties of Coconut Coir and Rice Husk Reinforced Natural Hybrid Composites

FPGA based area efficient implementation of DDR SDRAM memory controller using verilog HDL