Influence of 0.2% fe addition on zirconium conversion coating on aluminium alloy

Conversion coating on aluminium/0.2%Fe alloy developed from a zirconium nitrate/fluoride solution has been examined with scanning electron (SEM) and transmission electron microscopes (TEM) with attached energy dispersive X-ray (EDX) facilities. Zirconium-rich islands of thicker sections were observed in the SEM. The thin sections from the transmission micrographs revealed undulating metal/coating and coating/solution interfaces. This is consistent with anode/cathode reactions in the formation and growth of conversion coatings on metals, especially aluminium alloys. The coating comprises of zirconium rich surface which is contaminated or otherwise with aluminium and other species from the coating solution

Fabrication and Evaluation of Screw-like Fish Pelletizer

Good and balanced meals are required for fish to stay healthy and the production of these meals requires some machines like pelletizer. This study therefore contributes to the improvement of existing models of this machine by designing, fabricating and evaluating the performance of a new pelletizer. After fabrication, 5 kg fish feed ingredients weight was processed for 2.5 minutes in the machine in quadruplicate. The average discharge efficiency, percentage loss due to residue ingredients and production rate for the machine are 92.25 %, 7.75 % and 110.7 kg/h, respectively. The results showed that an increase in drying days led to a corresponding increase in percentage moisture content removal with a similar reduction in the weight of the pelletized fish meal. This machine will be of great assistant to medium and small-scale aquaculture farmers, thereby reducing the need for foreign sources of fish feed in fish farming sector

A review of various improvement strategies for joint quality of AA 6061-T6 friction stir weldments

Aluminium alloys are one of the choice materials with ever-increasing demands in manufacturing industries. The aluminium alloy 6 xx series such as AA6061-T6, has emerged as one of the promising materials utilized owing to its combination of favourable properties which include high strength to weight ratio, good ductility, excellent corrosion resistance and relatively low cost. These superior properties are responsible for its emergence and usage in the fabrication of aircraft wings and fuselages, yacht/ship construction, automotive rims and wheel spacers. However, joining of AA6061-T6 including the use of friction stir welding (FSW) has serious concerns because the mechanical and tribological properties of the AA6061-T6 welded joints deteriorate significantly compared with the base metal. This phe�nomenon has been attributed to the severe softening encountered at the stir zone (SZ) of the aluminium matrix during FSW. Other inherent challenges of FSW such as weld thinning, kissing bond and keyhole formation also contribute to the reduction in the weld joint quality. The softening phenomenon has been linked to the dissolution of the strengthening pre�cipitates (B00-Mg5Si6) as a result of high heat input during the welding process. Hence, this paper attempts to review the various improvement strategies adopted in the existing studies to improve the quality of AA 6061-T6 welded joint. These include parametric optimization, selection of appropriate tool design, pre and post heat treatments, adoption of different groove/hole designs for particle addition as well as the addition of reinforcement particles to the weld joint. The variants of FSW recently developed will also be considered. The findings from the review will generally be useful for future work on FSW of heat treated aluminium alloys. The evolution of FSW and its associated challenges are briefly discussed while the research areas yet to be harnessed are suggested for future works

Analysis of combustible municipal solid waste fractions as fuel for energy production exploring its physico-chemical and thermal characteristics

An investigation study on municipal solid waste generation and physicochemical characteristics of combustible fractions was carried out in Ilorin metropolis. This was driven by a need to meet energy demand and reduce the consequential effects of wastes for clean and green habits. Ilorin waste sector, requires detailed information on the physicochemical characteristics of the wastes fractions, to choose the appropriate method for waste management in the city. A240 litres bin volume of wastes was sampled 62 times within eight months at Lasoju dump-site. The conformity of the combustible wastes with the characteristics required of solid fuel was investigated. Manual sorting enables access to vital information about recovery and characteristics of waste components. Nine out of nineteen components characterized, were selected for Laboratory analyses. The results of the physical characterization, shows that 70% MSW generated is combustible. The proximate analysis reveals that the wastes contain more than 64% fixed carbon, 33 % volatile matter and 5 % of moisture content, while the ultimate analysis shows more than 29 % of carbon which can contribute to the calorific value of the MSW. Nitrogen is about 2.8 % and Sulphur about 0.2 %; the small average amount of Nitrogen and sulphur present, will cause reduction of emissions during combustion. The energy content of the MSW determined, using bomb calorimeter was about 20 MJ/kg. The results show that the MSW stream in Ilorin metropolis would serve as a reliable and sustainable renewable energy resource via combustion method

Reinforcement bar Corrosion - Causes and Management

Concretes are composite materials which decay as a result of steel corrosion in concrete structures is mostly accelerated in environments laden with chlorides and industrial effluent gases as well as harsh chemicals employed in and those generated from wastes in agricultural industries. This review summarises the effects of various environmental pollutants which promote deterioration of concretes with resultant corrosion of reinforcing bar (rebar). An overview of traditional and current methods for significant reduction of this mode of material deterioration is described. Discussions on management tools for rebar corrosion in agricultural and marine environments have been highlighted. Repair methods include the traditional application of patch repair mortar which has been modified with polymeric materials to improve adhesion and reduce porosity. The use of cathodic protection system to reduce rebar corrosion to its barest minimum has gained currency. Attention should be directed at corrosion reduction practices at the design and planning stages as well as modification concrete mixes with modified agricultural wastes/products and polymers

Reinforcement bar Corrosion - Causes and Management

Concretes are composite materials which decay as a result of steel corrosion in concrete structures is mostly accelerated in environments laden with chlorides and industrial effluent gases as well as harsh chemicals employed in and those generated from wastes in agricultural industries. This review summarises the effects of various environmental pollutants which promote deterioration of concretes with resultant corrosion of reinforcing bar (rebar). An overview of traditional and current methods for significant reduction of this mode of material deterioration is described. Discussions on management tools for rebar corrosion in agricultural and marine environments have been highlighted. Repair methods include the traditional application of patch repair mortar which has been modified with polymeric materials to improve adhesion and reduce porosity. The use of cathodic protection system to reduce rebar corrosion to its barest minimum has gained currency. Attention should be directed at corrosion reduction practices at the design and planning stages as well as modification concrete mixes with modified agricultural wastes/products and polymers

Tensile strength prediction by regression analysis for pulverized glass waste-reinforced aluminium alloy 6061-T6 friction stir weldments

AA6061-T6 is becoming a material of choice in the automobile, marine and aerospace industries because of its combination of relatively favourable and superior properties including high toughness, strength and excellent corrosion resistance. The major issue of concern about this material is the deterioration of these properties in the welded joint which has been established to improve through the additions of synthetic rein�forcements such as SiC, WC, Al2O3, B4C and SiO2. This study seeks to investigate the quality of pulverised glass waste-reinforced friction stir welded joints of AA6061-T6 within a process window (rotational speed: 900-1400 rpm; traverse speed: 25-63 mm/min; tilt angle: 1� - 2.5�) as well as developing a regression model predicting the tensile strength of the pulverised waste glass-reinforced AA6061-T6 friction stir welded joints at varying process parameters. The tensile strength of the weldment was determined using Instron universal testing machine while the model was developed using a new statistical method (analysis of variance and hierarchy rule). The effects of the interaction of the parameters on the joint quality were also determined. Optimum tensile strength of *185 MPa was achieved at rotational speed of 1120 rpm, traverse speed of 40 mm/min and tilt angle of 1.5.There is an improvement of about 37% over the unreinforced joint with tensile strength of *135 MPa. A model with a prediction accuracy of 92% was developed. The analysis of variance revealed that tool rotational speed, traverse speed and tilt angle had significant effects on the tensile strength of the weldments while the factors’ interactions do not show any significant contribution to the tensile strength. The model finds technical applications where timely selection of optimum process parameters is required for producing particulate-reinforced AA6061-T6 friction stir welded joints

Dataset for the development of a diagnostic schedule for a defective LC-195V5 CNC milling machine at FUTA central workshop

The dataset represented in this article describe a diagnostic schedule for a defective LC-195V5 CNC milling machine using PERT. The efficiency of the technicians who repaired the CNC machine tools was measured based on fault location within the shortest possible time. A diagnostic schedule was developed which showed the sequential means of troubleshooting within a possible shortest time. Two approaches were employed. Forward Pass (FP), which involved the diagnosis from electrical parts through Computer (CNC) to mechanical components and Backward Pass (BP) which involved the diagnosis from computer component through electrical parts to mechanical parts. Three different levels of expertise (trials) were used for each of the mode of diagnosis and the time to diagnose each component part was recorded. Two separate PERT network diagrams were drawn based on the inter-relationship of the component parts of the machine and their Critical Paths were determined

Joint quality enhancement of AA6061-T6 friction stir weldment by reinforcing with pulverized glass waste using different reinforcement strategies

The joint quality performance of AA6061-T651 friction stir weldments had been investigated in this study through addition of pulverized waste glass (PWG), palm kernel shell ash (PKSA) and synthetic silicon carbide (SSC) with a bid to enhancing some selected mechanical properties. Optimized processing parameters which include 1120 rpm rotational speed, 40 mm/min traverse speed, 1.5o tilt angle) and optimum reinforcement strategy (parallel hole) established from a preliminary investigation were utilized for the friction stir welding. The mechanical properties such as the tensile strength, hardness and impact energy were then further investigated. The results showed that the mechanical properties of all the reinforced welded joints improved significantly than the unreinforced joint having a relatively reduced joint performance of 132 MPa tensile strength, hardness of 45.3 HRB and impact energy of 39.4 J. The PWG-reinforced friction stir welded joint performed optimally at a tensile strength of 212.7 MPa, 72 HRB hardness and 54.5 J impact energy followed by the SSC-reinforced joint which exhibited 173.7 MPa tensile strength, 54.8 HRB hardness and impact energy of 41.7 J. Hence, 80%, 59% and 38% joint performance was exhibited through tensile strength, hardness and impact energy of PWG-reinforced friction stir weldments of AA6061-T651 against the unreinforced weldments

Optimization of chicken nail extracts as corrosion inhibitor on mild steel in 2M H2SO4

The inhibiting effects of Chicken Nails Extract (CNE) on Mild Steel corrosion in 2M H2SO4 were investigated in this study. The effect of the concentration of inhibitor (0.5–1.5 g/l), time (5–8 h) and temperature (40-70o c) on Inhibition efficiency were investigated using Response Surface Methodology. The Physiochemical analysis and proximate analysis of the CNE were investigated; the result showed that organic constituents were present which made the Chicken nails extract a good inhibitor. The rate of corrosion increases as time and temperature increase while the Inhibition efficiency was discovered to increase as the inhibitor concentration increases. The optimum conditions obtained were temperature 63.63 C, time 5 h and inhibitor concentration of 0.1 g/l. The optimum Inhibition Efficiency at these optimum conditions was predicted to be 74.04%. The micrographs result of Scanning Electron Micrographs analysis showed that in the presence of the inhibitor, there was a passive layer of a film formed on the surface. This study revealed that Chicken Nails Extract is a potentially good green inhibitor for Mild steel corrosion in 2M H2SO