Comparative Study Of Different Materials Research Articles

A Comparative Study of Different Materials for Manufacturing of Miniature Spur Gears by Spark Erosion Wire Cutting Process

Selection of suitable materials plays a key role in machining to produce durable and good quality micro parts and components as well as improve the productivity of machining processes. This paper presents the performance evaluation of Spark Erosion Wire Cutting (SEWC) for the manufacturing of miniature gears from different materials, namely stainless steel SS 304, aluminum 7075, copper, and brass. The major objectives of this performance evaluation of SEWC are to determine the effect of gear materials on the quality of the gears, the economic aspects of miniature gears, and the productivity of SEWC for fabricating miniature spur gears. The optimal range of SEWC parameters from past research works was considered for conducting experiments for this study. Four miniature spur gears were fabricated from each gear material. It was concluded from this study that 1) the use of SS 304 as miniature spur gear material results in a better surface finish than aluminum, copper and brass; 2) use of aluminum as miniature gear material is more productive than SS 304, copper and brass; 3) aluminum is more economical and material-efficient than SS 304, copper and brass to fabricate miniature gears by SEWC; 4) material lost in copper is higher as compared to other selected materials; and 5) cost of SS 304 miniature gear is more as compared to other fabricated gears by SEWC.

Comparative study of different materials for insulated pavement in cold regions

Pavements constructed on frost-susceptible subgrade layers are prone to deterioration from freezing in cold regions. A thermal insulation layer above the frost-susceptible subgrade layer in a pavement structure could effectively mitigate the deterioration due to frost action. The objective of study was to evaluate the thermal insulation performance of different insulating materials experimentally and numerically. Therefore, five large-scale pavement boxes, including one uninsulated pavement and four insulated pavements using different materials (i.e., XPS board, tire chips, foam glass aggregates (FGA), and foamed concrete), were constructed. The thermal insulation performance was studied under constant freezing condition and freeze-thaw cycles where the temperature profile of pavements was monitored. A finite element model was developed by considering the transient heat flow and the associated latent heat of fusion in the unbound granular layers. Correspondingly, the numerical simulation was conducted to extrapolate the temperature profile for pavement structures made by different insulating materials. The experimental results show that the XPS and FGA have the best overall insulation performance, followed by foamed concrete and tire chips. Results of the numerical simulation suggest that to achieve an equivalent level of insulation performance as a 5 cm thick XPS board under the same freezing conditions, insulating materials such as tire chips layer, FGA layer, foamed concrete layer, or recycled concrete aggregate should have insulation layer thicknesses of 40 cm, 25 cm, 30 cm, or 68 cm, respectively. In terms of cost-benefit analysis, the foamed concrete insulated pavement is the most expensive option, followed by uninsulated pavement, insulated pavements using FGA, tire chips, and XPS. This study highlights the critical role of the insulating material and the insulation layer thickness in cost-benefit thermal insulation for pavements in cold regions.

A comparative study of different materials used for solar photovoltaics technology

Photovoltaics are clean, abundant, and sustainable energy sources that has the potential to fulfill increasing global energy demand. A photovoltaic cell is a device that does the real work of converting solar energy to electrical energy. As solar photovoltaic will play a very crucial role in the future, it is essential to analyze and have comprehensive study based on materials and types of technologies. The paper presents a holistic review of three primary solar photovoltaic technologies, the dominant crystalline silicon photovoltaic, thin-film photovoltaic, and much recent emerging photovoltaic. The need for the energy transformation, evolution of technology, cell materials, cell performance, global market share, cost, and different properties for the corresponding solar photovoltaic technologies are equally assessed. In addition to this, the benefits and challenges of each photovoltaics technology are also analyzed. The comparative study of different photovoltaic technologies will help the reader to explore potential research scopes in the field of materials, design, technologies, and improvement in energy conversion of different solar photovoltaic technologies.

A comparative study of different materials (drinking water treatment sludge, nanoclay, and modified nanoclay) for simultaneous removal of hexavalent chromium and lead

Drinking water treatment sludge in large quantities was generated in the flocculation process of the treatment plant, all over the world. It considered the secondary raw material due to having valuable inorganic compounds such as iron. Herein, a novel green method was developed to recover iron from drinking water treatment sludge for synthesizing nanoscale iron supported on nanoclay by a lemon Beebrush polyphenol. The surface of nanoclay containing iron nanoparticles was modified with ethylenediamine for their applications as heavy metals adsorbent. The field emission scanning electron microscopy, energy-dispersive x-ray spectroscopy, thermogravimetric analysis, derivative thermogravimetry, and Fourier-transform infrared spectroscopy techniques were utilized to examine the adsorbents. Based on the results of energy-dispersive X-ray analysis, iron and nitrogen were successfully introduced into the structure of modified nanoclay. A batch adsorption system was used to investigate the simultaneous removal performance of hexavalent chromium and lead onto drinking water treatment sludge, nanoclay, and nanoclay-iron nanoparticle-ethylenediamine. The influence of factors, e.g., initial concentration, contact time, pH, adsorbent dosage, and temperature, were evaluated. The maximum uptake for chromium was 0.303, 0.352, and 0.984 mmol/g and for lead 0.03, 0.042, and 0.108 mmol/g at pH of 3 onto drinking water treatment sludge, nanoclay, and nanoclay-iron nanoparticle-ethylenediamine, respectively. The results show that the quantity of chromium and lead adsorbed onto modified nanoclay was more than 2.5-fold than that adsorbed onto unmodified nanoclay. The equilibrium adsorption data of hexavalent chromium and lead were fitted well with the Langmuir isotherm model (R2 > 0.97). Besides, the pseudo-second-order kinetic model demonstrated the kinetic adsorption of the metal ions. The thermodynamic constants suggested that the adsorption of lead by three adsorbents was exothermic and spontaneous while that of hexavalent chromium was endothermic. It leads to a finding that nanoclay-iron nanoparticle-ethylenediamine could be an effective adsorbent for heavy metals removal from water and wastewater.

Advanced materials and technologies for hybrid supercapacitors for energy storage – A review

Abstract Supercapacitors have become the most significant energy conversion and storage system in recent renewable and sustainable nanotechnology. Due to its large energy capacity and supply with relatively short time and longer lifetime, supercapacitors breakthrough in advance energy applications. This review presents a comparative study of different materials, working principles, analysis, applications, advantages and disadvantages of various technologies available for supercapacitors. The aim of this article is to discuss the possibility of hybrid supercapacitor for the next generation of energy technology. The development of composite materials containing a wide range of active constituents (e.g., graphene, activated carbon, transition metals, metal oxides, perovskites and conducting polymers) by in-situ hybridization and ex-situ recombination is also discussed. This review consecrated largely the contribution of combining all materials (electrode and electrolyte) and their synthesis process and electrochemical performance. Enduringly, the potential issues and the perspectives for future research based on hybrid supercapacitors in energy applications are also presented.

Material Selection for Microchannel Heatsink: Conjugate Heat Transfer Simulation

Heat dissipation during the operation of electronic devices causes rise in temperature, which demands an effective thermal management for their performance, life and reliability. Single phase liquid cooling in microchannels is an effective and proven technology for electronics cooling. However, due to the ongoing trends of miniaturization and developments in the microelectronics technology, the future needs of heat flux dissipation rate are expected to rise to 1 kW/cm2. Air cooled systems are unable to meet this demand. Hence, liquid cooled heatsinks are preferred. This paper presents conjugate heat transfer simulation of single phase flow in microchannels with application to electronic cooling. The numerical model is simulated for different materials: copper, aluminium and silicon as solid and water as liquid coolant. The performances of microchannel heatsink are analysed for mass flow rate range of 20-40 ml/min. The investigation has been carried out on same size of electronic chip and heat flux in order to have comparative study of different materials. This paper is divided into two sections: fabrication techniques and numerical simulation for different materials. In the first part, a brief discussion of fabrication techniques of microchannel heatsink have been presented. The second section presents conjugate heat transfer simulation and parametric investigation for different material microchannel heatsink. The presented study and findings are useful for selection of materials for microchannel heatsink.

Comparative Study of Different Materials for Occlusal Matrix Technique in Posterior Teeth

Posterior composite restorations are difficult to contour and polish due to their occlusal anatomy and opposing occlusion. Our study describes a technique for duplicating occlusal surface anatomy, using different dental materials that are able to copy anatomic details. The aim of the study was to evaluate the efficiency of occlusal matrix technique, by comparing technical ease of different dental materials. The study was conducted on extracted teeth which had intact occlusal surfaces or initial carious lesions at this level. An impression of the occlusal surface was made prior to cavity preparation, with four different dental materials: a flow composite, a dual-cure resin cement, a temporary acrylic resin (powder and liquid) and a temporary crown and bridge two-component material in a Unidose®. When the last layer of composite has been placed, the occlusal matrix was forced into the uncured composite to replicate the original occlusal surface, instead of performing manual curing and shaping as in the standard approach. Time needed for complete finishing the case, the hardness of each occlusal matrix and the final morphology obtained were evaluated. The main benefits of the occlusal matrix technique are the technical ease of use due to its simplicity and its high accuracy in reconstructing occlusal morphology. Although the shortest time needed for occlusal matrix preparation was for the dual-cure resin cement, the best oclusssal matrix was obtained with the temporary acrylic resin (powder and liquid).

Comparative Study of Different Materials with Al-Sic for Engine Valve Guide by Using FEM

In this work, an effort has been designed to raise the reliability of engine using Al-Sic composites with other alternatively materials for the engine valve guides. Aluminum matrix composites have found the most suitable inside automotive, aerospace and aircraft industries and contain the greatest promise for future year’s growth. The finite element analysis of the Al-Sic composite with Titanium alloy (Ti-834), Copper Nickel Silicon alloys (CuNi3Si), and aluminum bronze alloy as an alternative material for engine valve guide was done using Ansys 13.0 software. The stress analysis of engine valve guide under the different pressure and temperature is considered, the pressure is taken as from 10 MPa to 100 MPa with different temperatures varying from 600℃ to 650℃. The temperature, principal stress and principal strain distribution on the entire surface area of the engine valve guide were obtained. The stresses were observed to be well below the permitted stress for all the materials but the Al-Sic composites found the most suitable one. Valve guide is modeled in pro-engineer software and analysis is carried out in Ansys 13.0. The deformations and stresses induced due to structural and thermal loading is illustrated and discussed.