Microstructural characterisation, physical and chemical properties of rice husk ash as viable Pozzolan in building material: a case study of some Nigerian grown rice varieties

Recycling of agricultural wastes such as rice husk ash as pozzolan is being increasingly encouraged, particularly in developing countries. In this paper, preliminary investigation on the physical and chemical composit ions of r ice husk ash using different techniques was carried out. Scanning Electron Microscopy (SEM) images of the r ice husk ash showed residual p ores to be distributed within the ash sample, indicating th at the silica is a highly porous material with a large internal surface area . Samples burnt at 4000 C for 6 hours and 6000 C for 4 hours for ‘Bukus’ and ‘Soro/ Olomo nla’ show aggregates with clearly defined layers of loose flakes compared to ‘Faro 58’. The Energy dispersive x ray spectroscopy (EDX) analysis of rice husk ash performed to determine percentages of silica present in the samples were graphically represented. Nine elements (Al, Si, K, Ca, Br, Fe, Mg, Na, Mn) and their corresponding oxides (Al2O3 , SiO2 , K2O, CaO, Br, Fe2O3 , MgO, Na2 O, MnO) were detected with varying concentrations. The three varieties , on the average possess good silica content of over 50% considering the two varied temperature and time. Therefore , the chemical analysis results show that burning at combustion temperature of 6000 C for 4hrs, gives optimal result than at 4000 C for 6hrs because all the samples show high Silica content (Faro 58; 61.9, Bukus; 62.6 and Soro/Olomo nla; 59.5). Keywords : Rice husk ash, Scanning electron microscopy, Energy dispersive x - ray spectroscop

MODELING AND OPTIMIZATION OF SURFACE ROUGHNESS IN END MILLING OF ALUMINIUM USING LEAST SQUARE APPROXIMATION METHOD AND RESPONSE SURFACE METHODOLOGY

In end milling, accurate setting of process parameters is extremely important to obtained enhanced surface roughness (SR). Due to a recent innovation in mechanization made it possible to produce high quality manufacturing products. The perceptions of quality in mechanical products are their physical look that is the surface roughness (SR). The aim of this research work is to develop mathematical expression (M.E) and mathematical model using least square approximation method and Response Surface Methodology (RMS) to predict the SR for end milling of Al 6061 alloy. The process parameters that were selected as predictors for the SR are Spindle speed (V), axial depth of cut (a), feed rate (f) and radial depth of cut (d). 30 samples of Al 6061 alloy were carried out using SIEG 3/10/0010 CNC machines and each of the experimental result was measured using Mitutoyo surface roughness tester and Presso-firm. The minimum SR of 0.5 μm were obtained at a spindle speed of 2034.608 rpm, feed rate of 100 mm/min, axial depth of cut of 20 mm, and radial depth of cut 1.5 mm. Analysis of variances shows that the most influential parameters was feed rate. After the predicted SR has been obtained by using the two methods, average percentage deviation was calculated, the result obtained using least square approximation method (that is the mathematical expression) show the accuracy of 99% and Response Surface Methodology (RSM) mathematical model shows accuracy of 99.6% which is viable and appropriate in prediction of SR. When either of these models are applied this will enhance the rate of production

An Investigation of the Effects of Manufacturing Parameters On Properties of Binderless Boards Produced from Abura (Mitragyna Ciliata) Sawdust

The production of particle boards without the use of synthetic binders is desirable to prevent environmental problems. This study has produced experimental binderless boards from untreated sawdust from Abura wood using a laboratory press. Box-Behnken experimental design was utilized to investigate the effects of the pressing variables including pressure, temperature and pressing time. The density of the boards produced ranged between 523.69 and 738 kg/m3 which was within the range specified for medium density fibreboards . The maximum values for Modulus of Elasticity (MOE), Modulus of Rupture (MOR) and Internal Bonding Strength (IB) were 100.4 MPa, 1.1 MPa and 0.049 MPa, respectively. It was shown that, for the range of factors studied, pressure and the pressing temperature were the more significant factors in determining the density, MOE and IB. This study showed that the sawdust can potentially be used for the production of binderless boards

An Investigation of the Effects of Manufacturing Parameters On Properties of Binderless Boards Produced from Abura (Mitragyna Ciliata) Sawdust

The production of particle boards without the use of synthetic binders is desirable to prevent environmental problems. This study has produced experimental binderless boards from untreated sawdust from Abura wood using a laboratory press. Box-Behnken experimental design was utilized to investigate the effects of the pressing variables including pressure, temperature and pressing time. The density of the boards produced ranged between 523.69 and 738 kg/m3 which was within the range specified for medium density fibreboards . The maximum values for Modulus of Elasticity (MOE), Modulus of Rupture (MOR) and Internal Bonding Strength (IB) were 100.4 MPa, 1.1 MPa and 0.049 MPa, respectively. It was shown that, for the range of factors studied, pressure and the pressing temperature were the more significant factors in determining the density, MOE and IB. This study showed that the sawdust can potentially be used for the production of binderless boards

Dataset on experimental investigation of optimum carburizing temperature and holdingtime of bi-nano additives treatment of AISI 5130 steel

Investigation of optimum carburizing temperature and holding time on bi-nano additives treatment of AISI 5130 steel was presented in this study. AISI 5130 steel of 100 kg mass of 0.35% carbon content was buried in pulverized additives consisting of palm kernel and coconut shell using egg shell as an energizer. Four sets of 150�150�150mm3 steel boxes packed with additives mixed at varying weight ratio of 50:30:20 and sixty-four pieces of 20�20�5mm3 AISI 5130 steel were case hardened using muffle furnace (2500 °C maxcapacity) at respective temperatures and time of 950,1000,1050,1100 °C and 60,90,120,180 min. The core, interface and surface hardness of the treated samples with their respective weight loss, wear volume and rate were investigated. This data set could be used in nano-composite match mixed ratio and optimization of carburizing medium and time for any industrial used case hardened steel

Postharvest Losses of Tomato (Solanum Lycopersicum) in the Open Markets in Ibadan Metropolis

Postharvest losses of tomato pose serious threat on the economic viability of actors in the tomato production chain in Nigeria. Therefore, postharvest losses of tomato among marketers in Ibadan Metropolis of Oyo State Nigeria were investigated by the researchers. One hundred and twenty tomato marketers were chosen from the five food markets in Ibadan metropolis through a simple random sampling technique. The study adopted linear regression and descriptive statistics to analyze data. The outcomes of the investigation show that females were 92.5% and 88.3% were married. Capital is primarily raised through cooperative societies (57.5%). Postharvest losses of tomato accounted for 18.9% of purchase which represents ₦124,800/day. The major causes of PHLs are poor packaging (100%) and poor storage (100%) by the tomato marketers. Meanwhile, all the respondents (100%) adopted sorting to reduce PHLs of tomato. The regression analysis showed that education has a significant effect to reduce PHLs of tomato. The study concluded that huge postharvest and monetary losses of tomato are experienced by the tomato marketers. The study recommends provision of quality postharvest handling education to tomato marketers as a way of reducing PHLs of tomato in Ibadan

Impact of Heat Treatment on HSS Cutting Tool (ASTM A600) and Its Behaviour during Machining Of Mild Steel (ASTM A36)

Carburization is one the best heat treatment that responded well to hardening with Palm Kernel Shell giving the best hardness value. This work studied the influence of carburization on HSStool(ASTM A600) and its behaviour during machining of mild steel (ASTM A36). Composition of the samples (12 pieces of 180 x 12 x12 mm) HSS tools were checked using UV-VIS spectrometer and the tools were carburized with PKS at holding temperatures and time of 800, 850, 900,950 oC and 60,90 120 minutes using muffle furnance. The micro structural analysis, surface and core hardnessof the treated samples gave better results than the untreated samples when checked withsoft driven and optical microscope. It wasalso observed that increase in the feed rate and depth for length of cut of 50 mm significantly reduces the wear progression and thereby gave best machining time at maximum carburizing temperature and time(950 oC / 120 minutes) when it was used to cut mild steelon the lathe machine

Study of the Performances of Nano-Case Treatment Cutting Tools on Carbon Steel Work Material during Turning Operation

The degree of holding temperature and time play a major role in nano-case treatment of cutting tools which immensely contributed to its performance during machining operation. The objective of this research work is to carryout comparative study of performance of nano-case treatment tools developed using low and medium carbon steel as work piece. Turning operation was carried out under two different categories with specific work piece on universal lathe machine using HSS cutting tools 100 mm x 12mm x 12mm that has been nano-case treated under varying conditions of temperatures and timeof 800,850, 900, 950oC and 60, 90, 120 mins respectively. The turning parameters used in evaluating this experiment were cutting speed of 270, 380 and 560mm/min, feed rate of 0.15, 0.20 and 0.25 mm/min, depth of cut of 2mm, work piece diameter of 25mm and rake angle of 7o each at three levels. The results of comparative study of their performances revealed that the timespent in the machining of low carbon steel material at a minimum temperature and time of800°C, 60 mins were1.50, 2.17 mins while at maximum temperature and time of 950°C , 120 mins were 1.19, 2.02 mins. It was also observed that at a corresponding constant speed of 270,380 and 560mm/min at higher temperature and time, a relative increased in the length of cut were observed. Critical observation of the result showed that at higher case hardening temperature and time (950°C/120mins), the HSS cutting tool gave a better performance as lesser time was consumed during the turning operation

MODELING AND OPTIMIZATION OF SURFACE ROUGHNESS IN END MILLING OF ALUMINIUM USING LEAST SQUARE APPROXIMATION METHOD AND RESPONSE SURFACE METHODOLOGY

In end milling, accurate setting of process parameters is extremely important to obtained enhanced surface roughness (SR). Due to a recent innovation in mechanization made it possible to produce high quality manufacturing products. The perceptions of quality in mechanical products are their physical look that is the surface roughness (SR). The aim of this research work is to develop mathematical expression (M.E) and mathematical model using least square approximation method and Response Surface Methodology (RMS) to predict the SR for end milling of Al 6061 alloy. The process parameters that were selected as predictors for the SR are Spindle speed (V), axial depth of cut (a), feed rate (f) and radial depth of cut (d). 30 samples of Al 6061 alloy were carried out using SIEG 3/10/0010 CNC machines and each of the experimental result was measured using Mitutoyo surface roughness tester and Presso- firm. The minimum SR of 0.5 μm were obtained at a spindle speed of 2034.608 rpm, feed rate of 100 mm/min, axial depth of cut of 20 mm, and radial depth of cut 1.5 mm. Analysis of variances shows that the most influential parameters was feed rate. Afte

Cost of Corrosion of Metallic Products in Federal University of Agriculture, Abeokuta

The cost of corrosion has been increasing drastically due to the degradation of the metallic materials. This study was carried out to estimate the “Cost of Corrosion of Metallic Products in Federal University of Agriculture, Abeokuta (FUNAAB)”. Questionnaires were administered and interviews were also conducted to gather necessary information. The cost of corrosion from 2013-2015 was estimated and analysed with the aid of engineering economy method and statistical analysis method. For the cost of corrosion prevention methods, cleaning gave the highest cost contribution (69%), followed by the use of oil (30%), use of grease (1%), and painting gave zero percent of the total cost. While on the cost of corrosion maintenance methods, repair gave the highest cost contributions (66%), and prevention gave (34%) of the total cost. The overall cost of corrosion from (2013-2015) gave an upward trend, but a downward trend in future value and the annualized value. While the forecast cost from (2013-2016) at (95%) confidence level and (5%) significance level gave an upward trend. The present value, future value, and annualized value from (2013-2016) increased by (66%, 43%, and 75%) respectively. The total cost and the total annualized value of corrosion from (2013-2015) were estimated to be N 166,955,641 and N 93,791,024, and with the forecast (2013-2016) were found to be N 277,650,388 and N 163,672,460 respectively. Under the corrosion prevention methods and corrosion maintenance methods, cleaning and repair gave highest cost contribution respectively. Corrosion prevention methods need to be added to bring down the repair cost of those facilities for saving cost