Influence of reinforcements in friction stir processed magnesium alloys : insight in medical applications
- Authors: Adetunla, Adedotun , Akinlabi, Esther Titilayo
- Date: 2018
- Subjects: Composites , Magnesium , Mechanical properties
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/289865 , uj:31458 , Citation: Adetunla, A. & Akinlabi, E. 2018. Influence of reinforcements in friction stir processed magnesium alloys : insight in medical applications.
- Description: Abstract: Magnesium alloy shows great potential in medical devices such as wound closing devices, bone grafts and cardiovascular stents owing to its mechanical and biodegradable properties. However, its clinical applications are limited due to its biocompatibility and rapid corrosion. Since material corrosion and biocompatibility can be categorized under surface properties of biomaterials, this study employed a surface modification method to fabricate new alloys. Reinforcement of magnesium alloys with powders have engineered a new type of material regarded as metal matrix composites...
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Influence of multi-pass friction stir processing on microstructure and mechanical properties of die cast Al-7Si-3Cu aluminium alloy
- Authors: Baruch, L. John , Raju, R. , Balasubramanian, V. , Rao, A.G. , Dinaharan, I.
- Date: 2016
- Subjects: Friction stir processing , Overlap multi-pass , Microstructure , Mechanical properties
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/93804 , uj:20393 , Citation: Baruch, L.J. et al. 2016. Influence of multi-pass friction stir processing on microstructure and mechanical properties of die cast Al-7Si-3Cu aluminium alloy.
- Description: Abstract: The influence of overlap multi-pass friction stir processing on the microstructure and mechanical properties, in particular, strength, ductility and hardness of die cast Al-7Si-3Cu aluminium alloy was investigated. It was observed that with the increasing number of overlap passes friction stir processing resulted in significant refinement and redistribution of aluminium silicon eutectic phase with elimination of casting porosities. The microstructural refinement by the friction stir processing not only increases the ultimate tensile strength from 121to 273 MPa, but also increases the ductility as observed by the increase in fracture strain from 1.8% to 10%. Analysis of the fractured surface reveal that microstructural refinement obtained by friction stir processing plays a vital role in transforming the fracture mode from completely mixed mode to ductile mode of fracture with increasing number of passes. Change in the size, shape, morphology and distribution of eutectic silicon particles and elimination of porosities are the main reasons for the increase in tensile strength and ductility due to friction stir processing.
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A review on the influence of process parameters on powder metallurgy parts
- Authors: Edosa, Osarue Osaruene , Tekweme, Francis Kunzi , Gupta, Kapil
- Date: 2021
- Subjects: Composites , Mechanical properties , Microstructure
- Language: English
- Type: Journal artice
- Identifier: http://hdl.handle.net/10210/490435 , uj:44751 , Citation: Edosa, O.O., Tekweme, F.K. and Gupta, K., 2022. A review on the influence of process parameters on powder metallurgy parts. Engineering and Applied Science Research, 49(3), pp.433-443. , DIO:10.14456/easr.2022.44
- Description: Abstract: The capability of powder metallurgy (PM) process to produce high quality components/parts is largely dependent on the control of process parameters. To obtain the desirable quality characteristics or properties in the produced part, an appropriate combination of process parameters is required. This paper presents a detailed review of powder metallurgy process parameters and their effects on a wide range of properties while developing a wide range of metallic and composites products. Key process parameters in this study include compaction pressure, sintering temperature, sintering time, sintering atmosphere, lubrication and reinforcement percentage volume. Their influence on physical properties, mechanical properties and microstructure of PM parts are extensively discussed. An extensive literature study as reported in this paper reveals that compaction pressure, sintering temperature, time and sintering atmosphere highly influence part density and strength, whereas part hardness and wear are greatly affected by hard ceramic reinforcement addition, compaction pressure, sintering temperature and time. Die wall lubrication greatly improve the physical, mechanical properties and microstructure of PM components compared to powder mass lubrication. It is observed that the powder metallurgy process conducted at optimum parameters produce quality products. This paper aims to facilitate researchers and scholars by providing a detail knowledge of PM process parameters and their effects, for them to conduct research and development to establish the field further.
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A review article: the mechanical properties and the microstructural behaviour of laser metal deposited Ti-6Al-4V and TiC composite
- Authors: Erinosho, Mutiu, F. , Akinlabi, Esther Titilayo
- Date: 2016
- Subjects: Application , Laser technology , Mechanical properties
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/121859 , uj:20573 , Citation: Erinosho, M.F. & Akinlabi, E.T. 2016. A review article: the mechanical properties and the microstructural behaviour of laser metal deposited Ti-6Al-4V and TiC composite.
- Description: Abstract: Please refer to full text to view abstract
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The effects of rapid cooling on the improved surface properties of aluminium based coatings by direct laser deposition
- Authors: Fatoba, Olawale Samuel , Makhatha, Mamookho Elizabeth , Akinlabi, Esther Titilayo
- Date: 2017
- Subjects: Al-based coatings , Modification , Mechanical properties
- Language: English
- Type: Book Chapter
- Identifier: http://hdl.handle.net/10210/260637 , uj:27450 , DOI: http://dx.doi.org/10.5772/intechopen.71698. , Citation: Fatoba, O.S., Makhatha, M.E. & Akinlabi, E.T. 2017. The effects of rapid cooling on the improved surface properties of aluminium based coatings by direct laser deposition.
- Description: Abstract: The deterioration of materials during industrial application poses a serious threat to the materials structural integrity. A material’s susceptibility to wear and surface damage can be reduced by alteration of its surface chemistry, morphology and crystal structure. Therefore, modification of surface properties plays an important role in optimizing a material’s performance for a given application. Modern industrial applications require materials with special surface properties such as high hardness, wear and corrosion resistance, therefore materials engineers are vital to regularly examine how the microstructure of a material can be altered. Aluminium-based alloys have a wide application in the automotive, domestic and aerospace industries due to their excellent mechanical properties such as good weldability, sound castability and outstanding resistance to corrosion. The purpose of this research is to enhance inherent properties of the materials to create new products or improve on existing ones. The most effective engineering solution to prevent or minimize such surface region of a component is done by fibre lasers. It was concluded that Hypereutectic Al-Si alloys having transition metals are exceptional materials due to their specific properties. The addition of Cu, Fe, Cr, Si, Mg and Ni to Al-based alloys can improve the mechanical properties at both ambient and elevated temperatures.
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Physical, mechanical and thermal properties of high frequency microwave treated plantain (Musa Paradisiaca) fibre/MWCNT hybrid epoxy nanocomposites
- Authors: Imoisili, Patrick Ehi , Ukoba, Kingsley , Jen, Tien-Chien
- Date: 2020
- Subjects: Fiber , Hybrid , Mechanical properties
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/435626 , uj:37757 , Citation: Imoisili, P.E., Ukoba, K. & Jen, T.C. 2020. Physical, mechanical and thermal properties of high frequency microwave treated plantain (Musa Paradisiaca) fibre/MWCNT hybrid epoxy nanocomposites. , DOI: https://doi.org/10.1016/j.jmrt.2020.03.012
- Description: Abstract: Natural fibre reinforced polymer composite has many industrial applications especially inautomobile. However low mechanical and thermal property has limited its application. Inthis study, natural fibre reinforced hybrid nanocomposite was manufactured by the incorpo-ration of high frequency microwave treated Plantain (Musa paradisiaca) fibre and multiwalledcarbon nanotubes (MWCNT) using a single epoxy resin matrix. The consequence of harmo-nized existence of MWCNT at different loading (0.5−2 wt.%) on the physical, mechanicaland thermal Properties of the hybrid nanocomposite was examined, using the ultrasonictechnique for dispersion of nanoparticles and hand lay-up and compression moulding pro-cess for composite production. The experimental results demonstrate that the mechanicalproperties strength improve up to 52%, while up to 30% improvement was recorded formicro-hardness and impact strength, caused by increment in MWCNT content. Scanningelectron microscope (SEM) analysis reveals good mechanical dovetailing of hybrid fibreswith polymer matrix. Thermal conductivity has shown significant improvement up to 43%as MWCNT contents increases. These enhancements are primarily ascribed to the highaspect ratio, high modulus, strength and good dispersal of carbon nanotubes (CNT) in thehybrid nanocomposites.
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Scanning speed and powder flow rate influence on the properties of laser metal deposition of titanium alloy
- Authors: Mahamood, Rasheedat M. , Akinlabi, Esther Titilayo
- Date: 2017
- Subjects: Additive manufacturing , Mechanical properties , Optical microscopy
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/238165 , uj:24416 , Citation: Mahamood, R.M. & Akinlabi, E.T. 2017. Scanning speed and powder flow rate influence on the properties of laser metal deposition of titanium alloy.
- Description: Abstract: Ti4Al4V is an important aerospace alloy because of its excellent properties that include high strength to weight ratio and corrosion resistance. In spite of these impressive properties processing titanium is very challenging which contributes to the high cost of the material. laser metal deposition, an important additive manufacturing method is an excellent alternative manufacturing process for Ti6Al4V. The economy of this manufacturing process also depends on the right combination of processing parameters. The principal aim of this study is to know the optimum processing parameters that will result in deposit with sound metallurgical bonding with the substrate with proper mechanical property and better surface finish. This will help to reduce the need for expensive secondary finishing operations using this manufacturing process. This study investigates the influence of scanning speed and the powder flow rate on the resulting properties of the deposited samples. Microstructure, Microhardness and surface finish of Ti6Al4V samples that were produced using the laser metal deposition process over a range of scanning speeds, ranging from 0.02 to 0.12 m/s and powder flow rate of ranging from 0.72 to 6.48 g/min...
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Residual stress distribution and the concept of total fatigue stress in laser and mechanically formed commercially pure grade 2 titanium alloy plates
- Authors: Mjali, Kadephi V. , Els-Botes, Annelize , Mashinini, Peter M.
- Date: 2018
- Subjects: Mechanical properties , Titanium , Residual stress
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/273165 , uj:29096 , Citation: Mjali, K.V., Els-Botes, A. & Mashinini, P.M. 2018. Residual stress distribution and the concept of total fatigue stress in laser and mechanically formed commercially pure grade 2 titanium alloy plates.
- Description: Abstract: This paper discusses the investigation of residual stresses developed as a result of mechanical and laser forming processes in commercially pure grade 2 Titanium alloy plates as well as the concept of total fatigue stress. The intention of the study was to bend the plates using the respective processes to a final radius of 120mm using both processes. The hole drilling method was used to measure residual strains in all the plates. High stress gradients were witnessed in the current research and possible cases analyzed and investigated. The effects of processing speeds and powers used also played a significant role in the residual stress distribution in all the formed plates. A change in laser power resulted in changes to residual stress distribution in the plates evaluated. This study also dwells into how the loads that are not normally incorporated in fatigue testing influence fatigue life of commercially pure grade 2 Titanium alloy plates...
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Production and characterization of titanium carbide particulate reinforced AA6061 aluminum alloy composites using stir casting
- Authors: Moses, J. Jebeen , Dinaharan, I. , Sekhar, S. Joseph
- Date: 2016
- Subjects: Metal matrix composites , Stir casting , Microstructure , Mechanical properties
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/93822 , uj:20395 , Citation: Moses, J.J., Dinaharan, I. & Sekhar, S.J. 2016. Production and characterization of titanium carbide particulate reinforced AA6061 aluminum alloy composites using stir casting.
- Description: Abstract: Stir casting is an economical method to produce aluminum matrix composites. In the present work, composites of aluminum alloy AA6061 reinforced with various amounts (0, 5, 10 and 15wt. %) of TiC particles were prepared by stir casting technique. X-ray diffraction patterns of the prepared composites clearly revealed the incorporation of TiC particles without the presence of any other compounds. The microstructures of the composites were studied using optical and scanning electron microscopy. It was observed that the TiC particles distributed all over the composite and properly bonded to the matrix alloy. Local clusters of TiC particle were also seen in a few places. The result shows that the reinforcement of TiC particles enhances the microhardness, ultimate tensile strength and wear resistance of the composite. The details of fracture morphology, worn surface and wear debris are also presented in this paper.
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Microstructural and mechanical properties of spark plasma sintering of Ni2 Cr11Al powders synthesized by mechanical alloying for thermal barrier coating
- Authors: Omoniyi, F. I. S. , Olubambi, P. A. , Sadiku, R. E.
- Date: 2018
- Subjects: Mechanical alloying , Mechanical properties , Microstructure
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/282329 , uj:30407 , Citation: Omoniyi, F.I.S., Olubambi, P.A. & Sadiku, R.E. 2018. Microstructural and mechanical properties of spark plasma sintering of Ni2 Cr11Al powders synthesized by mechanical alloying for thermal barrier coating.
- Description: Abstract: Thermal barrier coatings (TBCs) systems are used to protect hot sections of industrial gas turbine blades against high temperature corrosion and oxidation. Currently, MCrAlY powders up to 100 μm in diameter are used in the production of thermal barrier coatings by industrial gas turbine component manufacturers. It has been found that nanocrystalline MCrAlY layer provide better oxidation behaviour than currently used microstructure MCrAlY layer at elevated temperature. In the present study, nanocrystalline NI22Cr11Al composites was synthesized using high energy planetary ball milling for different periods of time, and the dense NI22Cr11Al alloy was fabricated by using spark plasma sintering process at different temperatures ranging from 1000°C to 1200°C. The resultant powder particles, bulk and dense samples were characterised using scanning electron microscope (SEM), X-ray diffraction analysis (XRD) and Micro Vickers hardness test. The results indicated that mechanical milling process produce morphology changes, particle size increase, crystallite size decrease down to nanometric level (40 nm) and formation of Nano dispersions in the process.
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A molecular dynamics investigation of the temperature effect on the mechanical properties of selected thin films for hydrogen separation
- Authors: Oyinbo, Sunday Temitope , Jen, Tien-Chien
- Date: 2020
- Subjects: Molecular dynamics , Nanoindentation test , Mechanical properties
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/${Handle} , uj:39576 , DOI: 10.3390/membranes10090241 , Citation: Oyinbo, S.T. & Jen, T.C. 2020. A molecular dynamics investigation of the temperature effect on the mechanical properties of selected thin films for hydrogen separation.
- Description: Abstract: Please refer to full text to view abstract.
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