检索结果-南通市图书馆

Improving tribological and thermal properties of Al alloy using CNTs and Nb nanopowder via SPS for power transmission conductor

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2020年第2期30卷 333-343页

作者： Chika O.UJAH patricia popoola Olawale popoola Victor AIGBODION Philip OLADIJO Department of Chemical Metallurgical and Materials EngineeringTshwane University of TechnologyPretoria 0001South Africa Department of Electrical Engineering Tshwane University of TechnologyPretoria 0001South Africa Department of Metallurgical and Materials Engineering University of NigeriaNsukka 410001Nigeria Department of Chemical Materials and Metallurgical EngineeringBotswana International University of Science and TechnologyPalapye 12345Botswana Department of Mechanical Engineering University of JohannesburgJohannesburg 2000South Africa

This study aimed at improving the tribological and thermal properties of Al alloy using CNTs and Nb nanopowder as reinforcements and spark plasma sintering(SPS)as the fabrication *** SPS was conducted at 630℃,30 MPa,10 min,and 200℃/*** tribology test was run with ball-on-disc tribometer using steel ball as the counter *** the thermal test was processed with thermogravimetric analyzer(TGA)and laser flash apparatus(LFA).Results showed that the addition of 8 wt.%CNTs and 8 wt.%Nb reinforcements respectively decreased the coefficient of friction(COF)of the composite by 79%.The wear volume of the composite was decreased by 23%,and so was the wear ***,the thermal conductivity of the composite was equally improved by 44%.The tribology improvement was stimulated by a C film generated by CNTs and a protective Nb2O5 formed by Nb *** thermal conductivity was improved by the grain refining property of Nb and the high thermal conductivity of ***,these results indicated that Al-CNTs-Nb composite is a robust material for high transmission conductor capable of reducing sag and ensuring the durability of the composite.

关键词： tribology thermal conductivity spark plasma sintering Al-CNTs-Nb composite coefficient of friction

In-situ formation characteristic, tribological characterization and anti-corrosion properties of quaternary composites films

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2014年第10期24卷 3170-3180页

作者： Ojo Sunday Isaac FAYOMI Abimbola patricia Idowu popoola Department of Chemical Metallurgical and Materials EngineeringTshwane University of TechnologyP.M.B. X680 Pretoria South Africa

Improvements of wear and corrosion properties are essential characteristic in engineering application. A study was made on the structure, electro-oxidation and properties of fabricated Zn-Al-SnO 2-Ti O2（Zn-Al-Sn-Ti） thin films using electrodeposition technique from chloride bath. The microstructural studies were performed by scanning electron microscopy with attached energy dispersive spectrometer（SEM-EDS）, optical microscopy（OPM） and X-ray diffractogram（XRD）. The electrochemical oxidation and erosion behavior in 3.65% Na Cl medium were studied by potentiodynamic polarization technique and characterized by atomic force microscopy（AFM）. The hardness and wear behavior of the electrodeposited film were performed by high diamond dura scan microhardness tester and CERT UMT-2 reciprocating sliding machine. It was found that a successful co-deposition of composite and particle were attained. Homogeneous imbedded grain structure distribution and fine refinement of crystal with improved micromechanical behavior was achieved. The corrosion resistance, hardness and wear stability resistance of the fabricated quaternary films improved significantly in all varied process parameter.

关键词： co-deposition microstructural evolution anti-corrosion property composite materials

The Influence of Nickel on the Electrochemical Properties of Aluminium

在线全文

学校读者我要写书评

暂无评论

材料科学与工程（中英文版） 2010年第12期4卷 74-85页

作者： Abimbola patricia popoola Sisa Pityana Victoria Adams Department of Chemical and Metallurgical Engineering Tshwane University of Technology Pretoria South Africa Centre for Scientific and Industrial Research National Laser Centre Pretoria 0001 South Africa

Sacrificial Anode Stability and Polarization Potential Variation in a Ternary Al-xZn-xMg Alloy in a Seawater-Marine Environment

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Marine Science and Application 2016年第2期15卷 208-213页

作者： Abubakar Muazu Yaro Shehu Aliyu Malik Abdulwahab Abimbola patricia Idowu popoola Department of Mechanical Engineering Bayero University Kano P.M.B 3011 Nigeria Department of Metallurgical and Materials Engineering Ahmadu Bello University Zaria PM.B 1045 Nigeria Department of Chemical Metallurgical and Materials Engineering Tshwane University of Technology Pretoria X680 South Africa Department of Mechanical Engineering Ahmadu Bello University Zaria P.M.B 1045 Nigeria

In this paper, the effects of zinc （Zn） and magnesium （Mg） addition on the performance of an aluminum-based sacrificial anode in seawater were investigated using a potential measurement method. Anodic efficiency, protection efficiency, and polarized potential were the parameters used. The percentages of Zn and Mg in the anodes were varied from 2% to 8% Zn and 1% to 4% Mg. The alloys produced were tested as sacrificial anodes for the protection of mild steel in seawater at room temperature. Current efficiency as high as 88.36% was obtained in alloys containing 6% Zn and 1% Mg. The polarization potentials obtained for the coupled （steel/Al-based alloys） are as given in the Pourbaix diagrams, with steel lying within the immunity region/cathodic region and the sacrificial anodes within the anodic region. The protection offered by the sacrificial anodes to the steel after the 7th and 8th week was measured and protection efficiency values as high as 99.66% and 99.47% were achieved for the A1-6%Zn-l%Mg cast anode. The microstructures of the cast anodes comprise of intermetallic structures of hexagonal Mg3Zn2 and body-centered cubic A12Mg3Zn3. These are probably responsible for the breakdown of the passive alumina film, thus enhancing the anode efficiency.

关键词： sacrificial anode anode efficiency protection efficiency polarization potential intermetallic phase alloying elements theoretical current capacity flee electron seawater surface films

Corrosion Resistance ofAA6063-Type AI-Mg-Si Alloy by Silicon Carbide in Sodium Chloride Solution for Marine Application

在线全文

学校读者我要写书评

暂无评论

Journal of Marine Science and Application 2015年第4期14卷 459-462页

作者： Ojo Sunday Isaac Fayomi Malik Abdulwahab Abimbola patricia ldowu popoola Ferdinand Asuke Department of Chemical Metallurgical and Materials Engineering Tshwane University of Technology X680 Pretoria South Africa Department of Mechanical Engineering Covenant University P.M.B 1023 Ota Ogun State Nigeria Department of Metallurgical and Materials Engineering Ahmadu Bello University P. M.B 1045 Zaria Nigeria

The present work focused on corrosion inhibition of AA6063 type Al-Mg-Si alloy in sodium chloride （NaCI） solution with a silicon carbide inhibitor, using the potentiodynamic electrochemical method. The aluminium alloy surface morphology was examined, in the as-received and as-corroded in the un-inhibited state, with scanning electron microscopy equipped with energy dispersive spectroscopy （SEM-EDS）. The results obtained via linear polarization indicated a high corrosion potential for the unprotected as-received alloy. Equally, inhibition efficiency as high as 98.82% at 10.0 g/v silicon carbide addition was obtained with increased polarization resistance fRy）, while the current density reduced significantly for inhibited samples compared to the un-inhibited aluminium alloy. The adsorption mechanism of the inhibitor aluminium alloy follows the Langmuir adsorption isotherm. This shows that the corrosion rate of aluminium alloy with silicon carbide in NaCI environment decreased significantly with addition of the inhibitor.

关键词： corrosion resistance silicon carbide sodium chloride (NaCI) aluminium alloy interface inhibition efficiency thin film adsorption isotherm potentiodynamic electrochemical method marine application

Modeling and Simulation of Hydrogen Storage Device for Fuel Cell Plant

在线全文

学校读者我要写书评

暂无评论

Journal of Chemistry and Chemical Engineering 2012年第7期6卷 604-612页

作者： Akanji Olaitan Lukman Obadele Babatunde Abiodun Oluranti Sadiku-Agboola patricia Abimbola popoola Emmanuel Rotimi Sadiku Department of Chemical & Metallurgical Engineering Faculty of Engineering and The Built Environment Tshwane University of Technology Pretoria West 0001 Pretoria South Africa Department of Mechanical Engineering Faculty of Engineering and Built Environment Tshwane University of Technology Lynrrwoodridge 0001 South Africa

The article reviews a brief literature on the modeling of hydrogen storage device for fuel cell. Different dimensional approaches in modeling hydrogen absorption/desorption in a metal hydride reactor for use in fuel cell are summarized. Mathematical modeling equations involved are also stated. The effect of various operating parameters such as temperature, concentration, viscosity, thermal conductivity and time on the gas is also verified. The importance of various simulation software with reference to their major functions is also identified. The review concludes on the opportunities and challenges with the use of hydrogen as an alternative renewable energy.

关键词： Modeling simulation hydrogen storage fuel cell.

Parametric study of spark plasma sintering of Al_(20)Cr_(20)Fe_(25)Ni_(25)Mn_(10) high entropy alloy with improved microhardness and corrosion

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2022年第1期29卷 119-127页

作者： Andries Mthisi Nicholus Malatji A.patricia I.popoola L.Rudolf Kanyane Department of Chemical Metallurgical and Materials EngineeringTshwane University of TechnologyP.M.B.X680PretoriaSouth Africa

Multicomponent Al_(20)Cr_(20)Fe_(25)Ni_(25)Mn_(10) alloys were synthesized using spark plasma sintering at different temperatures(800,900,and 1000℃)and holding times(4,8,and 12 min)to develop a high entropy alloy(HEA).The characteristics of spark plasma-synthesized(SPSed)alloys were experimentally explored through investigation of microstructures,microhardness,and corrosion using scanning electron microscopy coupled with energy dispersive spectroscopy(EDS),Vickers microhardness tester,and potentiodynamic polarization,*** diffraction(XRD)characterization was employed to identify the phases formed on the developed *** EDS results revealed that the alloys consisted of elements selected in this work irrespective of varying sintering *** XRD,EDS,and scanning electron microscopy collectively provided evidence that the fabricated alloys were characterized by globular microstructures exhibiting face-centered cubic phase,which was formed on a basis of solid solution *** finding implies that the SPSed alloy showed the features of *** alloy produced at 1000℃ and holding time of 12 min portrayed an optimal microhardness of HV 447.97,but the value decreased to HV 329.47 after heat *** same alloy showed an outstanding corrosion resistance *** increase in temperature resulted in an Al_(20)Cr_(20)Fe_(25)Ni_(25)Mn_(10) alloy with superior density,microhardness,and corrosion resistance over the other alloys developed at different parameters.

关键词： high entropy alloy spark plasma sintering microhardness corrosion