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A comparative review on cold gas dynamic spraying processes and technologies

- Oyinbo, Sunday Temitope, Jen, Tien-Chien

  • Authors: Oyinbo, Sunday Temitope , Jen, Tien-Chien
  • Date: 2020
  • Subjects: Cold gas dynamic spraying , Spraying parameters , Deformatiom mechanism
  • Language: English
  • Type: Article
  • Identifier: http://hdl.handle.net/10210/436831 , uj:37907 , Citation: Oyinbo, S.T. & Jen, T.C. 2020. A comparative review on cold gas dynamic spraying processes and technologies. , DOI: https://doi.org/10.1051/mfreview/2019023
  • Description: Abstract: Cold gas dynamic spraying (CGDS) is a relatively new technology of cold spraying techniques that uses converging-diverging (De Laval) nozzle at a supersonic velocity to accelerate different solid powders towards a substrate where it plastically deforms on the substrate. This deformation results in adhesion to the surface. Several materials with viable deposition capability have been processed through cold spraying, including metals, ceramics, composite materials, and polymers, thereby creating a wide range of opportunities towards harnessing various properties. CGDS is one of the innovative cold spraying processes with fast-growing scientific interests and industrial applications in the field of aerospace, automotive and biotechnology, over the past years. Cold gas spraying with a wide range of materials offers corrosion protection and results in increases in mechanical durability and wear resistance. It creates components with different thermal and electrical conductivities than that substrates would yield, or produces coatings on the substrate components as thermal insulators and high fatigue-strength coatings, and for clearance control, restoration and repairing, or prostheses with improved wear, and produces components with attractive appearances. This review extensively exploits the latest developments in the experimental analysis of CGDS processes. Cold gas dynamic spraying system, coating formation and deposit development, description of process parameter and principles, are summarized. Industrial applications and prospectives of CGDS in future research are also commented.
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A molecular dynamics investigation of the temperature effect on the mechanical properties of selected thin films for hydrogen separation

- Oyinbo, Sunday Temitope, Jen, Tien-Chien

A simulation study of methane-hydrogen gas mixture permeation through nanoporous palladium membrane using molecular dynamics

- Oyinbo, Sunday Temitope, Jen, Tien-Chien, Gao, Qingwei, Lu, Xiaohua

Atomistic Simulations of Interfacial deformation and bonding mechanism of Pd-Cu Composite Metal Membrane using Cold Gas Dynamic Spray Process

- Oyinbo, Sunday Temitope, Jen, Tien-Chien, Zhu, Yudan, Ajiboye, Joseph Sehinde, Ismail, Sikiru Oluwarotimi

Comparative study of Hydrogen yield from magnesium waste products in Acetic acid and Iron chloride solution

- Hashe, Vuyo T., Jen, Tien-Chien

  • Authors: Hashe, Vuyo T. , Jen, Tien-Chien
  • Date: 2020
  • Subjects: Hydrogen , Waste magnesium , Hydrolysis reaction
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://hdl.handle.net/10210/434772 , uj:37650 , Citation: Hashe, V.T. & Jen, T.C. 2020. Comparative study of Hydrogen yield from magnesium waste products in Acetic acid and Iron chloride solution.
  • Description: Abstract: Low-grade magnesium (Mg) waste from post-consumer products and production waste cannot be recycled efficiently and economically. This work addresses this challenge by converting this waste into hydrogen. Hydrogen (H2) offers a wide range of benefits and the greatest of them all is its ability and flexibility to be used as a green energy carrier. In this work Mg waste is re-melted, loaded on one side of a stainless steel and allowed to solidify at room temperature to form a galvanic Mg stainless steel couple. Mg reacts slowly with water and releases hydrogen at room temperature and this is followed by the formation of magnesium hydroxide on its surface. Stainless steel net is considered as a metallic catalyst and two acids as accelerators reacting with the couples separately. A set of couples were used to generate hydrogen in 3.5% by weight acetic acid (CH3COOH). The experimental results show that a mean accumulated H2 volume of 3.17 – 3.21 litres was produced in 3600 seconds. Another set of couples produced H2 in 1.5 wt. % of iron chloride (FeCl3). The results confirmed FeCl3 as an excellent hydrolysis reaction accelerator with stainless steel as an effective catalyst. On average, the reaction yielded 2700mL of H2 over 3600 seconds which appear to be substantially higher than the litres achieve when CH3COOH was considered as an accelerator.
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Conceptualization of the optimal design of a hydroxyl booster dry cell for enhancing efficiency of internal combustion engines

- Chinguwa, Simon, Jen, Tien-Chien, Akinlabi, Esther T.

  • Authors: Chinguwa, Simon , Jen, Tien-Chien , Akinlabi, Esther T.
  • Date: 2020
  • Subjects: Dry cell , Hydroxyl , Internal combusion
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://hdl.handle.net/10210/437148 , uj:37948 , Citation: Chinguwa, S., Jen, T.C. & Akinlabi, E.T. 2020. Conceptualization of the optimal design of a hydroxyl booster dry cell for enhancing efficiency of internal combustion engines.
  • Description: Abstract: Current internal combustion engines (ICEs) are powered by fossil fuels which create the challenges of low combustion efficiency and the emission of greenhouse gases. This has negatively affected the environment, leading to global warming and climate change. Interim technologies can be implemented to reduce these effects whilst alternative technologies are being explored. This research aimed at selecting the most appropriate geometrical design of a hydroxyl booster dry cell, a device which operates on the principles of electrolysis to produce hydroxyl gas commonly referred to as Brown gas or HHO. When a voltage is applied to a body of water, it splits it into its base components, i.e. hydrogen and oxygen cold plasma, a mixture sometimes referred to as hydroxyl gas. The addition of hydroxyl gas into the combustion chamber of an ICE initiates a more complete combustion due to the explosive and diffusive nature of hydrogen accompanied by the cooling effect of water thus reducing potential for NOx formation. This leads to fuel savings, cost savings and reduced emissions. A rectangular hydroxyl booster dry cell was selected and designed, fabricated and tested for effectiveness. The HHO generator is later connected to the ICE system to check mainly on the positive contributions of this Brown’s gas as HHO is popularly known.
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Development of palladium nanoparticles deposition on a copper substrate using a molecular dynamic (MD) simulation : a cold gas dynamic spray process

- Oyibo, Sunday T., Jen, Tien-Chien, Zhu, Yudan, Olayinka, Abegunde Oluwatosin, Assa, Samson

Effect of frictional boundary conditions and percentage area reduction on the extrusion pressure of aluminum AA6063 alloy using FE analysis modelling

- Oyinbo, Sunday Temitope, Jen, Tien-Chien, Ismail, Sikiru O.

  • Authors: Oyinbo, Sunday Temitope , Jen, Tien-Chien , Ismail, Sikiru O.
  • Date: 2020
  • Subjects: Deformation Analysis , Extrusion Pressure , Friction factor
  • Language: English
  • Type: Article
  • Identifier: http://hdl.handle.net/10210/436610 , uj:37879 , Citation: Oyinbo, S.T., Jen, T.C. & Ismail, S.O. 2020. Effect of frictional boundary conditions and percentage area reduction on the extrusion pressure of aluminum AA6063 alloy using FE analysis modelling.
  • Description: Abstract: Finite Element Analysis was carried out to describe the effect of frictional boundary conditions and percentage reduction on deformation modelling (forward extrusion) of Aluminum AA6063 alloy. Curved die profiles of regular polygons (square, hexagonal, heptagonal, and octagonal) were designed using MATLAB R2009b and Autodesk Inventor 2013 to generate the coordinate and the solid CAD model of the die profile respectively form a circular billet. The numerical analysis was performed using DeformTM-3D commercial package with frictional boundary conditions of 0.38 and 0.75 representing the wet and dry condition and varying the percentage reduction of 50%, 70%, and 90%. The results of the temperature distribution, effective stress, effective strain, and strain rate were reported. As the percentage area reduction increases, the extrusion pressure also increases with an increasing frictional condition, and die length. Also, extrusion pressure decreases when the side of the polygon increases from square-shaped section follow by hexagonal shaped-section and least in octagonal shaped-section for both friction factors and percentage area reductions. For a given percentage reduction and cross-sectional area, there is no distinct difference between the predictive loads for the shaped-polygons. When the result of this analysis is compared with the experimental results from the literature, it is evident that DeformTM-3D is an effective tool for finite element analysis of non-isothermal deformation processes.
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Effect of frictional boundary conditions and percentage area reduction on the extrusion pressure of Aluminum AA6063 alloy using FE analysis modelling

- Oyinbo, Sunday Temitope, Jen, Tien-Chien, Ismail, Sikiru O.

  • Authors: Oyinbo, Sunday Temitope , Jen, Tien-Chien , Ismail, Sikiru O.
  • Date: 2020
  • Subjects: Deformation Analysis , Extrusion Pressure , Friction factor
  • Language: English
  • Type: Article
  • Identifier: http://hdl.handle.net/10210/439419 , uj:38230 , Oyinbo, S.T., Jen, T., Ismail, S.O. 2020: Effect of frictional boundary conditions and percentage area reduction on the extrusion pressure of Aluminum AA6063 alloy using FE analysis modelling.
  • Description: Abstract: , Finite Element Analysis was carried out to describe the effect of frictional boundary conditions and percentage reduction on deformation modelling (forward extrusion) of Aluminum AA6063 alloy. Curved die profiles of regular polygons (square, hexagonal, heptagonal, and octagonal) were designed using MATLAB R2009b and Autodesk Inventor 2013 to generate the coordinate and the solid CAD model of the die profile respectively form a circular billet. The numerical analysis was performed using DeformTM-3D commercial package with frictional boundary conditions of 0.38 and 0.75 representing the wet and dry condition and varying the percentage reduction of 50%, 70%, and 90%. The results of the temperature distribution, effective stress, effective strain, and strain rate were reported. As the percentage area reduction increases, the extrusion pressure also increases with an increasing frictional condition, and die length. Also, extrusion pressure decreases when the side of the polygon increases from square-shaped section follow by hexagonal shaped-section and least in octagonal shaped-section for both friction factors and percentage area reductions. For a given percentage reduction and cross-sectional area, there is no distinct difference between the predictive loads for the shaped-polygons. When the result of this analysis is compared with the experimental results from the literature, it is evident that DeformTM-3D is an effective tool for finite element analysis of non-isothermal deformation processes.
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Effect of thermosyphon limits on design of a taper thermosyphon drill for dry drilling operation

- Ncaba, Nkosana Ignetious, Wiykiynyuy, Nyuytifo Emmanuel, Jen, Tien-Chien, Ukoba, Kingsley

  • Authors: Ncaba, Nkosana Ignetious , Wiykiynyuy, Nyuytifo Emmanuel , Jen, Tien-Chien , Ukoba, Kingsley
  • Date: 2020
  • Subjects: Dry drilling , Thermosyphon , Heat pipe
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://hdl.handle.net/10210/428386 , uj:36841 , Citation: Ncaba, N.I. et al. 2020. Effect of thermosyphon limits on design of a taper thermosyphon drill for dry drilling operation.
  • Description: Abstract: This This paper focused on the effect of thermosyphon limits on the design of a taper thermosyphon drill for dry drilling operation. Although, other methods such as minimum quantity lubrication have been sought but the harmful effects of metal working fluids persist. This study however focuses on the design, fabrication and testing of a thermosyphon drill for eliminating the use of metal working fluids in drilling operations. The methodology included the design of a taper thermosyphon drill, analysis of the thermosyphon drill, manufacturing and testing of the thermosyphon drill. A virtual design and stress analysis of the reversed tapered thermosyphon was done using SolidWorks software. A high speed steel drill bit was manufactured to suit the design requirements of the thermosyphon. The thermosiphon was then fabricated within the machine shop floor using Electric Discharge Machining through method of spark erosion. A reverse tapered thermosyphon was designed to improve the optimal performance of the drill...
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Effect of thermosyphon limits on design of a taper thermosyphon drill for dry drilling operation

- Ncaba, Nkosana Ignetious, Wiykiynyuy, Nyuytifo Emmanuel, Jen, Tien-Chien, Ukoba, Kingsley

  • Authors: Ncaba, Nkosana Ignetious , Wiykiynyuy, Nyuytifo Emmanuel , Jen, Tien-Chien , Ukoba, Kingsley
  • Date: 2020
  • Subjects: Dry drilling , Thermosyphon , Heat Pipe
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://hdl.handle.net/10210/437136 , uj:37947 , Citation: Ncaba, N.I. et al. 2020. Effect of thermosyphon limits on design of a taper thermosyphon drill for dry drilling operation.
  • Description: Abstract: This paper focused on the effect of thermosyphon limits on the design of a taper thermosyphon drill for dry drilling operation. Although, other methods such as minimum quantity lubrication have been sought but the harmful effects of metal working fluids persist. This study however focuses on the design, fabrication and testing of a thermosyphon drill for eliminating the use of metal working fluids in drilling operations. The methodology included the design of a taper thermosyphon drill, analysis of the thermosyphon drill, manufacturing and testing of the thermosyphon drill. A virtual design and stress analysis of the reversed tapered thermosyphon was done using SolidWorks software. A high speed steel drill bit was manufactured to suit the design requirements of the thermosyphon. The thermosiphon was then fabricated within the machine shop floor using Electric Discharge Machining through method of spark erosion. A reverse tapered thermosyphon was designed to improve the optimal performance of the drill...
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Effects of defects on nanoporous Graphene and MOS2

- Oviroh, Peter Ozaveshe, Mohlala, Lesego M., Jen, Tien-Chien

Experimental and numerical prediction of extrusion load at different lubricating conditions of aluminium 6063 alloy in backward cup extrusion

- Oyinbo, Sunday Temitope, Ikumapayi, Omolayo M., Jen, Tien-Chien, Ismail, Sikiru O.

  • Authors: Oyinbo, Sunday Temitope , Ikumapayi, Omolayo M. , Jen, Tien-Chien , Ismail, Sikiru O.
  • Date: 2020
  • Subjects: Extrusion load , Lubricants , Strain rate
  • Language: English
  • Type: Article
  • Identifier: http://hdl.handle.net/10210/436602 , uj:37878 , Citation: Oyinbo, S.T. et al. 2020. Experimental and numerical prediction of extrusion load at different lubricating conditions of aluminium 6063 alloy in backward cup extrusion.
  • Description: Abstract: In the present research work using a backward cup extrusion (BCE) die profile, different lubricating conditions on aluminum alloy AA6063 have been experimentally and numerically investigated to predict the extrusion load. It was obvious that due to an increase in applications of the extrusion process, many researchers have worked on the extrusion process using different methods to achieve their aims. This experiment was conducted with three different lubricants namely: Castor oil, Palm Oil and tropical coconut oil; as well as without lubricants. Different lubricating conditions were employed of varying strain rates ranges from 1.5x10-3s-1, 2.0x10-3s-1, 2.5x10-3s-1, and 3.0x10-3s-1; Numerical analysis and simulation for dry and lubricated conditions during extrusion load were also performed using DEFORM 3D software. The results show that prediction extrusion load increases with increasing strain rates. The maximum extrusion load was found to be higher for extrusion without lubricants. In all cases of strain rate, palm oil showed a lower extrusion load compared to the other lubricants. Castor oil indicated the highest extrusion load when the experiment is carried out using lubrication. There was a consistent agreement between the result gotten from the experiment and simulation result of the extrusion load-strike curve.
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Fabrication and synthesis of SnOX thin films : a review

- Emeka, Nwanna Charles, Imosili, Patrick Ehi, Jen, Tien-Chien

  • Authors: Emeka, Nwanna Charles , Imosili, Patrick Ehi , Jen, Tien-Chien
  • Date: 2020
  • Subjects: Thin films , Tin oxide , Band gap
  • Language: English
  • Type: Article
  • Identifier: http://hdl.handle.net/10210/457872 , uj:40647 , Citation: Emeka, N.C., Imosili, P.E. & Jen, T.C. 2020. Fabrication and synthesis of SnOX thin films : a review.
  • Description: Abstract: Due to its exceptional electrical, optical, chemical and magnetic properties, tin oxide (SnO and SnO2), which is a functional material has gained enormous attention for use in a variety of applications. Films of SnOX have a direct band gap between the ranges of 2.2 and 3.6 eV, with these films finding usefulness in various functions such as; solar cells, transparent conducting oxides for gas sensors, lithium-ion batteries, microelectronics, and use in the optoelectronics industries. In order to satisfy the needs of a broad range of these applications, thin films with an extensive properties span defined by film composition, thickness, structural properties and morphology are required. This article explains the theory and research status of the various manufacturing processes of tin oxide. The purpose is to analyse the effects of the thin films through distinct forms of deposition. The general finding summarized in this research on SnOX showed that various researchers studied specific characteristics of tin oxide properties restricted by experimental conditions.
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Facile fabrication of vanadium sensitized silver titanium oxides (V-Ag/TiO2) photocatalyst nanocomposite for pollutants removal in river water

- Ntobeng, Mahubedu Khutso, Imoisili, Patrick Ehi, Jen, Tien-Chien

Feasibility of numerical simulation methods on the Cold Gas Dynamic Spray (CGDS) Deposition process for ductile materials

- Oyinbo, Sunday Temitope, Jen, Tien-Chien

  • Authors: Oyinbo, Sunday Temitope , Jen, Tien-Chien
  • Date: 2020
  • Subjects: Numerical models , Deformation , Plastic strain
  • Language: English
  • Type: Article
  • Identifier: http://hdl.handle.net/10210/457885 , uj:40649 , Citation: Oyinbo, S.T. & Jen, T.C. 2020. Feasibility of numerical simulation methods on the Cold Gas Dynamic Spray (CGDS) Deposition process for ductile materials. , DOI: https://doi.org/10.1051/mfreview/2020023
  • Description: Abstract: The techniques of cold gas dynamic spray (CGDS) coating involve the deposition of solid, high speed micron to nano particles onto a substrate. In contrast to a thermal spray, CGDS does not melt particles to retain their physico-chemical properties. There have been many advantages in developing microscopic analysis of deformation mechanisms with numerical simulation methods. Therefore, this study focuses on four cardinal numerical methods of analysis which are: Lagrangian, Smoothed Particles Hydrodynamics (SPH), Arbitrary Lagrangian-Eulerian (ALE), and Coupled Eulerian-Lagrangian (CEL) to examine the Cold Gas Dynamic Spray (CGDS) deposition system by simulating and analyzing the contact/impact problem at deformation zone using ductile materials. The details of these four numerical approaches are explained with some aspects of analysis procedure, model description, material model, boundary conditions, contact algorithm and mesh refinement. It can be observed that the material of the particle greatly influences the deposition and the deformation than the material of the substrate. Concerning the particle, a higher-density material such as Cu has a higher initial kinetic energy, which leads to a larger contact area, a longer contact time and, therefore, better bonding between the particle and the substrate. All the numerical methods studied, however, can be used to analyze the contact/ impact problem at deformation zone during cold gas dynamic spray process.
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Green technology extraction and characterisation of silica nanoparticles from palm kernel shell ash via sol–gel

- Imoisili, Patrick E., Ukoba, Kingsley O., Jen, Tien-Chien

Influence of single and double-atom metal doping on the electrocatalytic hydrogen evolution activity of 2D-MoS2 surface

- Mohlala, Lesego M., Oviroh, Peter O., Jen, Tien-Chien, Olubambi, Peter A.

Investigate the importance of mechanical properties of SWCNT on Doxorubicin anti-cancer drug adsorption for medical application: a molecular dynamic study

- Karimzadeh, Sina, Safaei, Babak, Jen, Tien-Chien

  • Authors: Karimzadeh, Sina , Safaei, Babak , Jen, Tien-Chien
  • Date: 2020
  • Subjects: Carbon nanotube , Doxorubicin , Drug delivery system
  • Language: English
  • Type: Article
  • Identifier: http://hdl.handle.net/10210/457898 , uj:40650 , Citation: Karimzadeh, S., Safaei, B. & Jen, T.C. 2020. Investigate the importance of mechanical properties of SWCNT on Doxorubicin anti-cancer drug adsorption for medical application: a molecular dynamic study.
  • Description: Abstract: Recently, nanostructures have become popular as carriers in drug delivery system due to their smaller particle sizes, drug molecule protection, and slow and controllable release of drugs. This study aims to investigate the effects of the mechanical properties and thermal conditions on the spontaneous adsorption of doxorubicin (DOX) molecules into the inside and onto the surface of carbon nanotubes (CNTs) by using quantum calculations and molecular dynamic simulations. First, Natural Bond Orbital (NBO) method was used to obtain the electrical charges of atoms in an aqueous solution. Secondly, molecular dynamic simulations (MD) were used to investigate 10 different systems with different properties. Based on the obtained results, it was suggested that doxorubicin molecules were spontaneously adsorbed toward CNT. By analyzing and comparing the variations of Van der Waals (VdW), electrostatic energies (EL), number of contacts between the drug molecules and CNTs and radial distribution function it was found that the variations of mechanical properties of CNTs, as well as the temperature conditions of environment, significantly affected the efficiency of spontaneous adsorption of doxorubicin toward the surface and inside CNTs.
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Mechanical and water absorption behaviour of potassium permanganate (KMnO4) treated plantain (Musa Paradisiaca) fibre/epoxy bio-composites

- Imoisili, Patrick Ehi, Jen, Tien-Chien

  • Authors: Imoisili, Patrick Ehi , Jen, Tien-Chien
  • Date: 2020
  • Subjects: Water absorption , Bio-composite , Muse paradisiaca
  • Language: English
  • Type: Article
  • Identifier: http://hdl.handle.net/10210/435602 , uj:37754 , Citation: Imoisili, P.E. & Jen, T.C. 2020. Mechanical and water absorption behaviour of potassium permanganate (KMnO4) treated plantain (Musa Paradisiaca) fibre/epoxy bio-composites. , DOI: https://doi.org/10.1016/j.jmrt.2020.05.121
  • Description: Abstract: The use of environmentally friendly agro-waste fibres as reinforcement has opened a newdirection to polymer composite science. Research has suggested that changing the surfaceof the fibre by both physical and chemical processes improves the efficiency of the naturalfibre/polymer matrix. This research explores the kinetic and function of water absorptionand its relevance for the mechanical properties of potassium permanganate (KMnO4) treatedplantain (Muse Paradisiaca) fibres reinforced epoxy bio-composite. Treated fibres were char-acterized by wide-angle X-ray diffraction (XRD), Fourier transform infrared (FT-IR), scanningelectron microscope (SEM) and thermogravimetric analysis (TGA). The XRD study shows asignificant shift in the crystallographic parameters of the material, the FTIR spectral indi-cates the fractional elimination of wax, hemicellulose and lignin substance. TGA indicatesthat the thermal stability of the fibres was improved following treatment. Ruptured sampleswere studied using a SEM. The analysis indicates that, owing to the water penetration of thefibre matrix interface and prolongation of the water-immersion cycle, there was a decreasein the tensile and flexural strength of the bio-composites. Nevertheless, the mechanicaland water-resistant properties have been strengthened by KMnO4. The mechanism andkinetic of water absorption reveals a Fickian kind of diffusion and propensity to followFickian behaviour thus creating prospects and reliability of the bio-composite to be usein engineering and structural applications.
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