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The Effect of Machining Parameters on the Cutting Forces, Tool Wear, and Machined Surface Roughness of Metal Matrix Nano Composite Material
E. Y. El-Kady,
A. M. Gaafer,
M. H. G. Ghaith,
T. Khalil,
A. A. Mostafa
Issue:
Volume 4, Issue 3, June 2015
Pages:
43-50
Received:
13 March 2015
Accepted:
7 April 2015
Published:
23 April 2015
Abstract: The aim of the present study is to investigate the effect of machining parameters on the cutting forces, tool wear, and machined surface roughness of metal matrix nano composite material through dry turning operations. Composites specimens manufactured from aluminum alloy metal matrix and reinforced with different weight fractions of silicon carbide nano particulates were used to conduct the experimental work. Stir-casting method followed by squeezing technique were used to fabricate the nano composites specimens. The machinability tests were conducted through different cutting conditions using carbide inserts tools material. The machinability characteristics such as surface roughness of the machined specimens, types of chip, cutting forces in the direction of main cutting motion, and tool wear were investigated through the experimental conditions. The results showed improve in surface roughness by increasing the cutting speed and the weight fraction percent of the SiC nanoparticulates. On the other hand the main cutting force component as well as tool flank wear were increased by increasing the weight fraction of SiC nanoparticulates. Moreover the force component increased with increasing the feed rate and depth of cut, however the cutting forces were decreased by increasing the cutting speed while the flank wear increase.
Abstract: The aim of the present study is to investigate the effect of machining parameters on the cutting forces, tool wear, and machined surface roughness of metal matrix nano composite material through dry turning operations. Composites specimens manufactured from aluminum alloy metal matrix and reinforced with different weight fractions of silicon carbid...
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Effect of Annealing and Surface Passivation on Doped SnO2 Thin Films Prepared by Spray Pyrolysis Technique
Patrick Mwinzi Mwathe,
Robinson Musembi,
Mathew Munji,
Francis Nyongesa,
Benjamin Odari,
Walter Njoroge,
Bernard Aduda,
Boniface Muthoka
Issue:
Volume 4, Issue 3, June 2015
Pages:
51-58
Received:
13 April 2015
Accepted:
17 April 2015
Published:
27 April 2015
Abstract: In this study doped SnO2 thin films have been prepared by spray pyrolysis technique using an alcoholic precursor solution consisting of stannic chloride (SnCl4.5H2O), ammonium fluoride (NH4F) and palladium chloride (PdCl2). Optimization on the deposition parameters was done so as to obtain high quality thin films. The effect of varying the Fluorine content on the optoelectronic properties of F: SnO2 thin films was studied. Data for transmittance and reflectance in the wavelength range from 300nm – 2500nm was obtained using the solid spec 3700DUV spectrophotometer. Electrical characterization of the thin films was done using the four point probe method at room temperature. Post deposition treatment of the thin films by annealing in air then passivating in nitrogen gas environment was done in a tube furnace at 4500C. Sheet resistivity for the as prepared F: SnO2 was found to be 0.4599 Ωcm and 0.00075 Ωcm being the highest and lowest sheet resistivity at 22.74 at% F and 16.41at% F doping in SnO2 respectively. Low sheet resistivity of F: SnO2 thin films is due substitutional incorporation of F ions instead of oxygen ions into the crystal lattice of SnO2 thin films which increases free carrier concentration. The effect of annealing generally was found to improve on the electrical conductivity of the thin films which is due to increase in carrier mobility and density. Passivation on the other hand had a slight opposite effect. Effects of annealing and passivation on doped SnO2 thin films band gap energy and their transparency was insignificant, rendering the doped SnO2 thin films good choice for making a transparent thin film gas sensors.
Abstract: In this study doped SnO2 thin films have been prepared by spray pyrolysis technique using an alcoholic precursor solution consisting of stannic chloride (SnCl4.5H2O), ammonium fluoride (NH4F) and palladium chloride (PdCl2). Optimization on the deposition parameters was done so as to obtain high quality thin films. The effect of varying the Fluorine...
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Comparism of Cure Modeling of Unsaturated Polyester Based Composites Using Microwave and Autoclave Assisted Hand Lay-Up Process in Cylinderical Mould
Adefemi Adeodu,
Christopher Anyaeche,
Oluleke Oluwole,
Temitayo Azeez
Issue:
Volume 4, Issue 3, June 2015
Pages:
59-66
Received:
21 August 2014
Accepted:
21 August 2014
Published:
26 May 2015
Abstract: Modeling of composite curing process is required prior to composite production as this would help in establishing correct production parameter and method of curing thereby eliminating costly trial and producing an effective method of curing a particular polymeric composite. The main objective of this work is to compare the difference between modeled microwave and conventional autoclave heating methods in producing polyester-aluminum and polyester- carbon black composites. This will establish the effectiveness of a curing method in the production of a particular polymer composite i. e, prediction of best possible trends during microwave and conventional autoclave heating with regards to effect of heating rate on degree of cure of the composites. The numerical models were constructed by taking into account heat transferred by electromagnetic energy (microwave) and heat transferred by conduction (conventional autoclave) through the resin/filler mixture, as well as kinetic heat generated by cure reaction. The numerical solution of the mathematical models presented were discretized using forward finite differences of the RungeKuta method and finally solved using MATLAB® Computer programming language. It was observed that curing of the samples was achieved faster in microwave than conventional autoclave method as microwave heat transfer by electromagnetic energy produces volumetric heat flow as compared to conventional autoclave whose heat transfer by conduction generates transverse heat flow to the samples. This implies that in the production process of polymer-matrix composites, electromagnetic energy through microwave was able to produce faster heating rate; thus, an effective method of curing in the production process of polymer-metal composites.
Abstract: Modeling of composite curing process is required prior to composite production as this would help in establishing correct production parameter and method of curing thereby eliminating costly trial and producing an effective method of curing a particular polymeric composite. The main objective of this work is to compare the difference between modele...
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Effect of Microwave Curing on the Tensile Property of Particulate Reinforced Polymer Matrix Composites
Adefemi Adeodu,
Ilesanmi Daniyan,
Temitayo Azeez,
Charles Omohimoria
Issue:
Volume 4, Issue 3, June 2015
Pages:
67-74
Received:
8 May 2015
Accepted:
20 May 2015
Published:
1 June 2015
Abstract: Polymer composites by and large found suitable for many specific applications in the field of electrical, electronics, marine, aerospace and microelectronics. Thus a new technique for processing polymer composites has been explored and one such is microwave curing. The roles of microwave in the post curing of polymer matrix composites cannot be under estimated, as it has the capacity to improve the mechanical properties of the composite produced. The aim of the study is to determine the effect of microwave post curing on the tensile property of aluminum reinforced and carbon black reinforced unsaturated polyester composites. This effect was compared with that post cured using conventional oven with the objective of investigating the significance of microwave curing on the tensile strength of the produced composites. A specific study comprising of aluminum filled polyester based composite and carbon black filled polyester based composite were investigated using two different composite curing methods (microwave and conventional thermal heating). The investigation, through experimentation was based on mechanical property (tensile strength) of the produced composites. Comparing the results of the post-curing of the composites using microwave and conventional methods, there is direct relationship between the tensile strength and the percentage weight fraction of the fillers with respect to the post curing methods. 30% aluminum filled, post cured in microwave has 0.01 MPa tensile strength, 20% aluminum filled (microwave) has 0.0076MPa while 30% aluminum filled (conventional oven curing) has 0.0092MPa and 20% aluminum filled (conventional oven curing) has 0.0068MPa.It was concluded that post-curing of the particulate composites through microwave is able to improve the tensile strength better as compared to thermal conventional method.
Abstract: Polymer composites by and large found suitable for many specific applications in the field of electrical, electronics, marine, aerospace and microelectronics. Thus a new technique for processing polymer composites has been explored and one such is microwave curing. The roles of microwave in the post curing of polymer matrix composites cannot be und...
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