Browsing by Author "Aweda, J.O."
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Item Archachatina marginata bio-shells as reinforcement material in metal matrix composites(International Journal of Automotive and Mechanical Engineering, 2017) Kolawole, M.Y.; Aweda, J.O.; Abdulkareem, S.Snail shells (SnS), which represent the discarded bio-shell waste of snails’ remnants from restaurants and eateries constitute a serious degree of environmental threat with little or economic value. The effective utilisation of this waste into a green metal matrix composite as a low cost reinforcement material applicable in the automotive industry in lieu of its present hazardous impact had stimulated the research interest. Hence, this paper studies the potential utilisation of SnS as a low cost reinforcement material in the metal matrix composites (MMCs) by means of a characterisation technique. The mineralogical composition and physical properties of the snail shell powder was carried out using the density determination, thermogravimetric analysis (TGA), refractoriness, energy dispersive X-ray (SEM/EDX), X-ray fluorescent (XRF) and the X-ray diffraction (XRD) analysis at 0, 800, 850 and 900 oC calcined temperatures for 3hrs. The results obtained show that the snail shell powder possesses chemical hard phase oxides (CaO, Fe2Al2O3, Cr2O3, SiO2, MnO and NiO) at all calcined temperature values. The maximum amount of these phases was formed at a 900 oC calcined temperature. The XRD analysis also confirmed the presence of calcite (Ca6C6O8), lime (Ca4O4) and portlandite (CaO2) as the thermally stable major hard phases of the SnS calcined at 900 oC. The density and refractoriness temperature of the snail shell powder as obtained in this study are 1.63g/cm3 and 1400 oC. The TGA result shows that the SnS attained its thermal stability at 840 oC. The above results imply that SnS with (9.4-25.9) % lesser density when compared with agro or industrial wastes reinforcement material (flyash, coconut shell ash, maize husk, bagasse) in the metal matrix composite looks promising as a reinforcing material in the production of light weight metal matrix composites at low costs. Also, the high refractoriness temperature of the snail shell particle suggested it as a suitable candidate reinforcement material in the production of thermal resistance MMCs applicable in automotive components such as pistons and connecting rods.Item Assessment of properties of natural moulding sands in Ilorin and Ilesha, Nigeria(USEP Journal of Research Information in Civil Engineering, 2009) Aweda, J.O.; Jimoh, Y.A.The mechanical and permeability properties of natural sand deposits at Ilesha (south west) and Ilorin (middle belt) in Nigeria used in the foundry as moulding sand for casting of non-ferrous metals were investigated. The aim was to determine the optimum moisture content (OMC) for appropriate foundry works. The variation of the green strength of the moulding sand with the mixing water content was conducted to establish the OMC of 8% and 9% respectively for Ilesha and Ilorin sands. The corresponding values of the green compression strength of 52kN/m2 and 50kN/m2 , dry compression strength of 285kN/m2 and 300kN/m2 , shatter index values of 38 and 37 and the permeability index of 50 and 47.5 for Ilorin and Ilesha deposits respectively obtained at OMC of 8-9% were found adequate to produce sound casting of non-ferrous metals. The results indicate that with water addition in the range of 8-9%, the natural sands exhibit appropriate casting properties for non-ferrous metals in accordance with the standards and specifications of the America Foundry Society (AFS).Item Computer software simulation of cooling loads determination in buildings(Journal of The Nigerian Institution of Mechanical Engineers, 2017) Aweda, J.O.; Ibitoye, O.A.Accurate determination of the cooling load units in private and commercial buildings is an essential factor in human comfort as it relates to human efficiency and well-being of those that dwell or operate within such buildings. In this study, a computer simulation was developed for the determination of optimum cooling loads for air conditioning in a building. In the developed programme, input parameters used include building height, wall thickness, wall material, number of occupants, number and types of doors and windows. The computer simulation considered all intricate parameters that may lead to drop in the cooling loads. The programme was versatile, easy to operate and suitable for the determination of appropriate cooling load in any building. Results show that the computer programme developed can be employed for the determination of cooling loads for commercial buildings, worship centres and private homes.Item Design, Fabrication and Performance Evaluation of Awning/Canopy for Thermal Comfortability(Journal of Engineering and Technology, 2017) Ajao, K.R.; Yahaya, T.; Kolawole, M.Y.; Aweda, J.O.This paper presents the design, fabrication and performance evaluation of retractable awning/canopy system for thermal comfortability. It consists of frame (mild steel bars), linear actuator, fabric (acrylic), adapter, roller pathways and photo sensor (for easiness of control). After fabrication and coupling of the whole components of the retractable awning and connecting to the adapter and power source for performance test evaluation, it was observed that, the actuator arm which was coupled to the fabric began projecting outward and once the photo sensor was shaded from sunlight using a dark material, the fabric retracted into the roller. Also it was noted that, shading the window provided a reduced solar heat gain factor of 28.16W as compared to the solar gain factor of 498.54 W before shading the window with a cooling load of 415.37 W achieved. This can be incorporated into a building plans especially those at the sun heating direction and temperature region to reduce inner temperature aid air-conditioner loading for longer life and efficient operation.Item Determination of temperature distribution in squeeze cast aluminium using the semi-empirical equations method(Journal of Materials Processing Technology, 2009) Aweda, J.O.; Adeyemi, M.B.The effects of parameters such as applied pressure, die pre-heat temperature, delay time and retention time of applied pressure on the temperature distributions within the casting have been considered. The results using this method were compared with those of experimental and heat transfer differential equations’ methods and found to be about 1.7% higher in value. The semi-empirical equations’ method can be used to predict the temperature distribution of other metals and alloys at any location, if the empirical equations relating the heat transfer coefficients to applied pressures and solidifying temperatures for their three stages of solidification are known.Item Development and performance evaluation of Jominy end quench apparatus(Pacific Journal of Science and Technology, 2017) Aweda, J.O.; Abegunde, S.O.; Mahamood, R.M.This study was on the development and performance evaluation of a Jominy end-quench apparatus used for the determination of the hardenability of metals. The fabrication of the apparatus was undertaken bearing in mind the availability of the materials and cost implications of the apparatus. Stainless steel was used for the water prone areas to avoid corrosion while mild steel was used for other areas that are not exposed to water or other quenching fluids during operation. Fifty-four samples were prepared for the performance evaluation on the developed Jominy apparatus and were heated to temperatures of 850 0C, 900 0C, and 950 0C before quenching in the apparatus. Water and brine (pH values 6.5 and 5.6, respectively) were used as quenchants in the determination of hardenability of the specimens. The results obtained from the tests showed that Brinell hardness values reduced as distance from the quenched surface increases. Water quenched samples produced higher hardness value at lower quenching temperature while brine quenched specimens had higher Brinell hardness value at higher heating temperatures. When compared with the standard, the results obtained were very close which make the developed apparatus suitable for hardenability test of metals.Item Effect of coolant temperature on machining characteristics of high carbon steel(Covenant Journal of Engineering Technology, 2018) Ogedengbe, T.S.; Abdulkareem, S.; Aweda, J.O.This paper reports the effect of super-cooled coolant on machining of high carbon steels. The development of a cooling system to reduce the temperature of water-soluble coolant to 7-9oC from ambient temperature was employed in this work to improve the process performance. The experiments were performed using cooled and ambient temperatures by employing Taguchi L-18 orthogonal array to design the experimental runs. The cutting speed, feed rate and depth of cut were machining parameters used, while the tool-work piece interface temperature was monitored using digital thermometer with k-type thermocouple wire. The selected control factors are material removal rate (MRR) and surface roughness (SR). The experimental results were analyzed using Minitab 16. The main effects and percentage contributions of various parameters affecting surface roughness and material removal rate were discussed, and optimal cutting conditions were determined. It was observed that surface finish improved by 65% with the use of the developed super-cooled system. The reduction in coolant temperature played a vital role in improving surface finish during machining high carbon steels.Item Effect of coolant temperature on the surface finish during turning of Titanium Alloy Ti6A14V(International Journal of Engineering Materials and Manufacture, 2018) Ogedengbe, T.S.; Abdulkareem, S.; Aweda, J.O.High temperature generated and stresses induced as a result of turning of Ti6Al4V results in poor surface finish. The aim of this study was to investigate the effect of coolant temperature on the surface roughness of Ti6Al4V which is a core material used as an implant. A cooling system was developed to reduce the temperature of the coolant (soluble oil) from room temperature to 2oC. Ti6Al4V was turned in dry and cooled (at temperatures 5, 7, 9 and 11 conditions. The experiment was designed using central composite design of (Response surface methodology) Design Expert 11.0 to generate an array and optimize the machining parameters. The machining parameters used were cutting speed, feed rate, depth of cut and coolant temperature. Results analyses show that cutting speed and depth of cut had considerable effect on surface roughness of Ti6Al4V. Surface roughness reduced when coolant temperature was reduced. The results of this study shows that turning Ti6Al4V at a very low cutting temperature will ensure a better surface finish.Item Effects of applied pressure and die temperature on the electrical conductivity of squeeze cast aluminium rods(Journal of Technological Development, 2007) Aweda, J.O.; Adeyemi, M.B.Item Effects of mixing ratios of cow dung, cassava peel and rice husk on the thermodynamic properties and composition of biogas in anaerobic digester(Advances in Multidisciplinary & Scientific Research Journal, 2016) Olorunmaiye, J.A.; Adegun, I.K.; Ogunniyi, O.J.; Aweda, J.O.; Ajiboye, T.K.; Abdulkareem, S.Item Effects of squeeze casting parameters on temperature distribution during casting of aluminium(Journal of Applied Science and Technology, 2009) Aweda, J.O.; Adeyemi, M.B.The effects of squeeze casting parameters, such as delay time and retention time of applied pressure and die preheating, on Temperature distribution during casting of aluminium were investigated. Increased applied Pressure and die pre-heating produced higher peak solidifying temperatures during squeeze casting of molten aluminium. Longer pressure retention time and shorter delay time gave higher peak solidifying temperature and product of excellent cast properties. The correlation between experimental measurements and computed numerical values of applied pressure, die heating temperature, delay times and retention times was very good.Item Effects of thermal treatment processes (TTP) on some of the mechanical properties of welded 0.165% carbon steel(Journal of Production Engineering, 2017) Shuaib-Babata, Y.L.; Adewuyi, R.A.; Aweda, J.O.One of the major causes of structural failure in service is attributed to failure in its parts, especially at the welded joints. Engineers and other users of low carbon steel tend to find solution to this problem by considering the application of Post weld heat treatment (TTP).The Microstructure and mechanical properties of heat-treated and untreated welded low carbon steel samples were determined. Simulation of the specimens was also generated using Autodesk Inventor Simulation CFD 2015 Application Software. The CFD model (simulation) showed clearly the visual style wireframe and shaded mesh (XY, and XZ planes and the temperature profiles for different passes), which is a veritable tool to evaluate residual stress that is likely to happen in real welding process. The results also revealed that better quality mechanical behaviour of welded low carbon steel is elicited by post-weld normalizing and annealing TTP.Item Evaluation of mechanical and electrical properties of squeeze cast 1xxx aluminium(Nigerian Research Journal of Engineering and Environmental Studies, 2018) Kolawole, M.Y.; Aweda, J.O.; Abdulkareem, S.The effect of squeeze cast pressure on the mechanical and electrical properties of 1xxx aluminium was experimentally studied. Aluminium (1xxx) metal was melted and poured into a preheated split die at 700±10 oC. Varying values of pressures were applied on the cast using Vega hydraulic press to produce sound cast samples. Mechanical, microstructural and electrical properties of cast products were examined on Monsanto universal tensile testing machine (UTM), Rockwell hardness tester and DC 4 probes wire respectively. The results of the investigations revealed that squeeze cast pressure influenced the microstructure through grain refinement which led to enhancement of the mechanical properties of the metal. Improvement of 41.03 % in hardness at applied pressure of 190 MPa and 200% in tensile strength at applied pressure of 127 MPa were obtained for the squeeze cast metal. There was an increase in electrical conductivity by 18.5 % at 127 MPa applied squeeze cast pressure. Squeeze casting is thus presumed to be a suitable processing route for improving the mechanical and electrical properties of aluminium metal of 1xxx series.Item Evaluation of some squeeze cast parameters of aluminium(USEP Journal of Research Information in Civil Engineering, 2007) Aweda, J.O.Effects of applied pressures and die pre-heat temperatures on the heat transfer coefficients of aluminium were determined using the solidification temperature histories of the cast metal. The heat transfer coefficients at the cast metal/steel mould interface during solidification of squeeze cast aluminium were investigated using the inverse heat conduction method. The heat transfer coefficients were determined by both experimental and numerical methods. The results show an increase in the value of heat transfer coefficients with applied pressure and a decrease with high die pre-heat temperatures. The numerical heat transfer coefficients were in good agreement with the experimental values.Item Experimental determination of heat transfer coefficients during squeeze cast of aluminium(Journal of Materials Processing Technology, 2009) Aweda, J.O.; Adeyemi, M.B.Heat transfer coefficients during squeeze cast of commercial aluminium were determined, by using the solidification temperature versus time curves obtained for varying applied pressures during squeeze casting process. The steel mould/cast aluminium metal interface temperatures versus times curve obtained through polynomial curves fitting and extrapolation was compared with the numerically obtained temperatures versus times curve. Interfacial heat transfer coefficients were determined experimentally from measured values of heating and cooling temperatures of steel mould and cast metal and compared with the numerically obtained values and found to be fairly close in values. The values of the heat transfer coefficients were found to increase with increase in applied pressures and to decrease with fall of solidifying temperatures corresponding to three distinct solidification stages namely, liquidus, liquidus–solidus and solidus stages. Below temperatures of 500 0C, the effect of the increase in heat transfer coefficients with applied pressure application becomes less significant and the drop in values of the heat transfer coefficients with solidification temperatures at any applied pressures remains fairly constant. The peak values of heat transfer coefficients obtained for as-cast (no pressure application) and squeeze cast (pressure application) of aluminium are 2975.14 and 3351.08 W/(m2K), respectively. Empirical equations, relating the interfacial heat transfer coefficients to the cast aluminium surface temperatures and applied pressures at three distinct temperature range intervals, were also derived and presented.Item Health hazard of traffic noise: Perceptions of dwellers on Tanke – University Road, Ilorin, Nigeria(Pacific Journal of Science and Technology, 2012-11) Aweda, J.O.; Jimoh, Y.A.The corresponding qualitative wellness (health) by the residents and roadside businesses around a motorized urban arterial was reported. The traffic sound level manifesting on the nodes and links was quantified by the equivalent noise level (L) of 73.5 dB (A), a value that is higher than the WHO (World Health Organization) allowable threshold for the comfort and wellness of residential communities was obtained. The perception of the dwellers around the studied arterial about the prevailing traffic induced noise pollution agreed with the common health stress indicators of headache, insomnia and annoyance, among others. It is recommended that the Nigerian noise level bench mark of 90 dB (A) be reviewed to a lower value in order to reflect the global best practices on noise pollution control and wellness of human dwellers around a motorised corridor.Item Heat transfer assessment of straw bale walled room(2010) Adedeji, A.A,; Aweda, J.O.; Ajimotokan, H.A.This research work explores the thermal performance of straw bale walled building (of 0.14 W/m2K) in holistic sense, with concepts that determines the interrelation of internal and external heat gain and loss, building envelope performance, the thermal demand of occupant and the balance point. The calculation result has shown that an outdoor temperature of 17OC will balance the internal heat gain to produce a comfortable temperature of 24.5OC inside the room Considering the solar heat gain of 78.2 W/m2 at the wall surface area, the amount of balance point required has shown the insulation efficiency of the strawbale masonry with a constant temperature inside the room with time variation.Item Improving the electrical properties of aluminium metal through squeeze casting process(NSE Technical Transactions, 2008) Aweda, J.O.Squeeze casting is a new permanent mould casting process that produces products with improved mechanical and electrical properties. The effects of squeeze casting processing conditions (applied pressure and die temperatures), on the heat transfer coefficients and electrical properties of squeeze casting of aluminium have been investigated. Interfacial heat transfer coefficients were determined experimentally from measured values of heating and cooling temperatures of steel mould and cast metal respectively. A computer programme was developed to compute the temperature distributions in both the cast metal and steel mould and heat transfer coefficients in squeeze casting of aluminium. The predicted results show that high applied pressures and low die temperatures result in a high heat transfer coefficients across the casting / steel mould interface, which leads to increase in solidification and cooling rates of the cast metal. The experimental obtained values were compared with the numerical values and found to show good agreement between the predicted results and the experimental measured data.Item Industrial Safety(University of Ilorin, Nigeria, 2017) Aweda, J.O.; Mahamood, R.M.; Abdulrahaman, K.O.Item Influence of ferrosilicon manganese on the sulphur content and microstructure in the production of austempered ductile iron (ADI)(2017) Alabi, A.G.F.; Aweda, J.O.; Aluko, F.I.This study considers the effect of ferrosilicon manganese addition to austempered ductile iron, (ADI) in order to reduce its sulphur level for improved engineering applications of the material. The cast samples were austenitised in a mixture of potassium chloride, sodium chloride and barium chloride solutions and austempered in sodium nitrate and potassium nitrate solutions. Ferrosilicon manganese was added to ADI in various amounts ranging from between 47 to 326 g. The study revealed that the sulphur level retained in ADI decreased from 0.088 wt % for as-cast to 0.027 wt % when 93 g of ferrosilicon manganese was added. Below this amount of ferrosilicon manganese addition, there was no significant reduction in the sulphur level recorded in ADI. The microstructure of the metal revealed bigger graphite nodules scattered in ferrite solutions for the situation when the sulphur level was 0.027 wt. %. From the study, it was discovered that addition of small amount of ferrosilicon manganese was required to produce ADI of low level sulphur content to make the metal more acceptable for other engineering applications