This paper reports a compressive study on the utilization of rice husk (RH) as an important agro ... more This paper reports a compressive study on the utilization of rice husk (RH) as an important agro waste and reinforcement for composites fabrication. It also reports in details, a review of the physical and mechanical properties of RH composites and it intensively highlighted the knowledge gaps that need to be filled in the respective research areas. Furthermore, it discusses the potential of RH composites to be used in photonics, construction materials, and automotive and furniture applications, based on their strength and thermal characteristics. It also revealed that, extensive efforts can make rice husk a material for sustainable development since it has the potential to reduce greenhouse emissions, reduces material costs and abundantly affordable. Keywords: Rice Husk, Composites, Matrix, Reinforcement
The aim of the current paper is to study the hardness behaviour of carbon nanotube reinforced alu... more The aim of the current paper is to study the hardness behaviour of carbon nanotube reinforced aluminium (CNT-Al) nano composite material under nanoindentation and Vickers micro hardness techniques. The four different types of nano-composites with 1, 1.5, 2.0 and 2.5 wt% CNT indented by diamond Berkovich indenter in sub microns. The Vickers micro hardness test was performed using a Wilson Wolpert Vickers micro hardness tester. The results showed that the value of hardness increases with the increasing of CNT percentage in Al matrix up to 2 wt%. The highest hardness was obtained from 1.5 wt% CNT-Al nano-composite with the value of 1.90 GPa. From the CNT-Al load-displacement curve a good bonding property was observed between the reinforcement and the matrix material due to the same trend followed with other strong materials such as steel and silicon. However, there is a significant enhancement in the Vickers micro hardness of the 1.5 wt% CNT-Al nano-composite compared to other CNT reinforcement nano-composites. The highest hardness with the value of 102 VH was obtained from 1.5 wt% CNT-Al nano-composite which is three times higher than pure Al.
_________________________________________________________________________________ ABSTRACT--The c... more _________________________________________________________________________________ ABSTRACT--The current paper study the hardness behaviour of Kano cattle horn under nanoindentation and micro hardness tests. Five different samples were generated and level A, B, C, D and E cut along the whole length of the horn from the skull to the tip respectively. The samples were indented by diamond Berkovich indenter in sub microns for the nano hardness test. The Vickers micro hardness test was performed using a Wilson Wolpert Vickers micro hardness machine. The results showed that the value of hardness is increasing with the increasing length of the horn. The hardness increased from the skull to the middle of the horn length and starts decreasing gradually to the tip of the horn. Both tests confirmed that the hardness value is approximately higher at the middle of the horn. The range of hardness values of sample A, B, C, D and E obtained using nanoindentation results are 0.24-0.32 GPa, 0.24-0.28
The frictional behaviour of three different nano-composites such as 1.5 wt %, 2.0 wt % and 2.5 wt... more The frictional behaviour of three different nano-composites such as 1.5 wt %, 2.0 wt % and 2.5 wt % CNT Al nano-composite materials developed by powder metallurgy process has been studied with pin-on-disc tribometer, sliding against AISI52100 steel disc. The tribological properties of pure aluminium and carbon nanotube reinforced aluminium nano-composite were investigated and compared in this current study. Experiments were conducted using different sliding velocities of 0.5, 0.65 and 0.8 m/s and a normal load of 5, 7.5 and 10 N. Variations of coefficient of friction with the duration of rubbing at different normal loads and sliding velocities are investigated. It was revealed from the results that, coefficient of friction varies with the duration of rubbing, normal load and sliding velocities. It was clearly observed that, coefficient of friction increases for a certain duration of rubbing and after that it remains constant for the rest of the experimental time. Furthermore, the r...
There is a growing interest for novel materials of dissimilar metals due to higher requirements n... more There is a growing interest for novel materials of dissimilar metals due to higher requirements needed for some critical engineering applications. In this research, different dissimilar weld joints of high strength low alloy (HSLA) and 316 austenitic stainless steel grades were successfully produced using shielded metal arc welding (SMAW) process with 316L-16 and E7018 electrodes. Five variations of welding currents were employed within the specified range of each electrode. Other welding parameters such as heat inputs, welding speeds, weld sizes, arc voltages and time of welding were also varied. Specimens for different weld joint samples were subjected to microstructural studies using optical and scanning electron microscopes. The impact toughness test was also conducted on the samples using Izod impact testing machine. The analysis of the weld microstructures indicated the presence of type A and AF solidification patterns of austenitic stainless steels. The results further showed...
In this study 10 soil and 11 ground water samples were randomly collected, and the 222Rn concentr... more In this study 10 soil and 11 ground water samples were randomly collected, and the 222Rn concentrations were measured using a DURRIDGE RAD7 electronic radon detector. The radon concentration in ground water ranged from 0.53 BqL-1 to 5.13 BqL-1 with a mean value 2.37 BqL-1. The results show that all the groundwater samples collected have 222Rn concentrations below the US EPA Maximum Contaminant Level (MCL) of 11.1 BqL–1 (for states without radon monitoring policy and enhanced indoor air programs). All the ground water samples also have 222Rn concentrations below MCL of 100 BqL–1 recommended by EU. The annual effective dose due to ingestion (Hing) of 222Rn in the groundwater ranged from 0.00386 – 0.03744 mSvyear-1 with a mean value of 0.01706 mSvyear-1. These values are within the ICRP recommended reference level of 1 mSvy–1 for the intake of the radionuclide in water by the general public for a prolonged exposure. The effective radium content, radon mass exhalation rate and alpha ind...
Asian Journal of Engineering and Technology, Apr 25, 2014
The current paper study the hardness behaviour of Kano cattle horn under nanoindentation and micr... more The current paper study the hardness behaviour of Kano cattle horn under nanoindentation and micro hardness tests. Five different samples were generated and level A, B, C, D and E cut along the whole length of the horn from the skull to the tip respectively. The samples were indented by diamond Berkovich indenter in sub microns for the nano hardness test. The Vickers micro hardness test was performed using a Wilson Wolpert Vickers micro hardness machine. The results showed that the value of hardness is increasing with the increasing length of the horn. The hardness increased from the skull to the middle of the horn length and starts decreasing gradually to the tip of the horn. Both tests confirmed that the hardness value is approximately higher at the middle of the horn. The range of hardness values of sample A, B, C, D and E obtained using nanoindentation results are 0
The dispersion quality is the major concern in nanocomposite development as it determines the hom... more The dispersion quality is the major concern in nanocomposite development as it determines the homogeneity of the enhanced mechanical and tribological properties of the composite. This work study the morphology of aluminium powder in the CNTs-Al nanocomposite prepared with different weight percentage of CNT in aluminium matrix using powder metallurgy route under high energy planetary ball milling operations at varying time and speed of milling of 2, 3hrs and 250, 300 rpm respectively. The preliminary mixing of CNTs and aluminium powder in a tube via manual shaking and the speed used could be the main contributing factor in achieving uniform dispersion of CNT in aluminium matrix within short time. Evidence of FESEM morphology with significant reduction of milling time confirmed that CNT was homogeneously dispersed and distributed into Al matrix.Key words: Milling parameter, CNT-Al nanocomposite, Homogenous dispersion
Titanium (Ti-6Al-4V) alloy is very attractive for many applications due to its high strength-to-w... more Titanium (Ti-6Al-4V) alloy is very attractive for many applications due to its high strength-to-weight ratio and high corrosion resistance. Even then, with these attractive properties, it has poor shear strength and surface wear properties. This study is therefore undertaken to investigate the effect of sliding parameters on the surface wear behavior of Ti-6Al-4V alloy. Pin-like specimens of the alloy were produced and subjected to sliding motion on a pin-on-disk apparatus using different speeds, loads and sliding distances. The surface and specific wear rates of the alloy were evaluated as the main output of the study. Results indicate that the most severe surface wear rate of over 0.008 mm3/sec is experienced under conditions of low disk speed (50 rpm) with high input weight (46.5 N). Higher sliding distance is also found to affect the severity of the surface wear rate. All results of specific wear rates evaluated indicate that Ti-6Al-4V alloy can be classified as a low surface we...
Research works are being done to substitute heavy material with a suitable lighter weight and che... more Research works are being done to substitute heavy material with a suitable lighter weight and cheaper material which has better properties for this particular application. Processing route plays a significant role in developing the material for any application with effective cost and environmental factors and careful selection of processing route is especially very important for brake disc material. In this paper, a comprehensive review has been done on material and processing route in view of selecting alternative lightweight and cheaper materials for aircraft brake disc application. The advantages and disadvantages between aluminium metal matrix composite and other materials as well as the advantages of powder metallurgy route with other processes are presented for better understanding of the materials and process selection. Finally, emphasis has given on lightweight and cheaper carbon nanotube aluminium matrix (CNT-Al) nano-composite material with specific processing route as a case study. This is mainly based on material selection using material selection process which showed CNT-Al as an excellent candidate material for brake disc application.
Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, ... more Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.
International Journal of Engineering Materials and Manufacture
The effect of heat treatment on welded joints using the shielded metal arc welding (SMAW) on thre... more The effect of heat treatment on welded joints using the shielded metal arc welding (SMAW) on three different types of steel with different carbon ratios under constant conditions such as the welding current 120A, voltage 80V, Diameter 10 mm and angle 60 degree. Hardness tests chemical composition analysis were carried out and it was observed that, high carbon steel has the highest hardness of about 459 on maximum HV value, followed by the low carbon steel with the hardness of 316HV maximum and medium carbon experience the least value of 208HV. Hardness increases with low carbon content as shown in the experimental results which deduced that the low carbon steel used was confirmed to be the high-strength-low-alloy steel of grade 8620-HSLA-Nickel-Chromium-Molybdenum steel. The microstructure of the base metal was analysed before heating to support the results of chemical analysis. Nickel percentage of up to 0.147% and Chromium 0.083%. Molybdenum was just 0.030% which contributed in af...
The paper studied the microstructure of cattle horn using scanning electron microscope (SEM) to s... more The paper studied the microstructure of cattle horn using scanning electron microscope (SEM) to study its bonding nature. Five different samples were generated and level A, B, C, D and E cut along the whole length of the horn from the skull to the tip respectively. The samples were accordingly cut to round shapes to a diameter of 15.0mm to suit the mounting position and smoothened for easy passage of the rays. The thickness of specimen is 2.0mm. Samples are grinded directly using emery paper with grit size as follows: 180, 240, 320, 400, 600, 800, 1200 and 1500. After grinding, the samples are subjected to polishing using alumina solution of 0.5 followed by 0.3 particle size. From the morphology of the five samples analysed using SEM it was found the horn has an interesting natural structure arrange in a form of layers in a wave like form which varies from sharp to narrow width of the wave like structure and later flat from the tip of the horn to the skull. And the layers are unifor...
This paper reports a compressive study on the utilization of rice husk (RH) as an important agro ... more This paper reports a compressive study on the utilization of rice husk (RH) as an important agro waste and reinforcement for composites fabrication. It also reports in details, a review of the physical and mechanical properties of RH composites and it intensively highlighted the knowledge gaps that need to be filled in the respective research areas. Furthermore, it discusses the potential of RH composites to be used in photonics, construction materials, and automotive and furniture applications, based on their strength and thermal characteristics. It also revealed that, extensive efforts can make rice husk a material for sustainable development since it has the potential to reduce greenhouse emissions, reduces material costs and abundantly affordable. Keywords: Rice Husk, Composites, Matrix, Reinforcement
The aim of the current paper is to study the hardness behaviour of carbon nanotube reinforced alu... more The aim of the current paper is to study the hardness behaviour of carbon nanotube reinforced aluminium (CNT-Al) nano composite material under nanoindentation and Vickers micro hardness techniques. The four different types of nano-composites with 1, 1.5, 2.0 and 2.5 wt% CNT indented by diamond Berkovich indenter in sub microns. The Vickers micro hardness test was performed using a Wilson Wolpert Vickers micro hardness tester. The results showed that the value of hardness increases with the increasing of CNT percentage in Al matrix up to 2 wt%. The highest hardness was obtained from 1.5 wt% CNT-Al nano-composite with the value of 1.90 GPa. From the CNT-Al load-displacement curve a good bonding property was observed between the reinforcement and the matrix material due to the same trend followed with other strong materials such as steel and silicon. However, there is a significant enhancement in the Vickers micro hardness of the 1.5 wt% CNT-Al nano-composite compared to other CNT reinforcement nano-composites. The highest hardness with the value of 102 VH was obtained from 1.5 wt% CNT-Al nano-composite which is three times higher than pure Al.
_________________________________________________________________________________ ABSTRACT--The c... more _________________________________________________________________________________ ABSTRACT--The current paper study the hardness behaviour of Kano cattle horn under nanoindentation and micro hardness tests. Five different samples were generated and level A, B, C, D and E cut along the whole length of the horn from the skull to the tip respectively. The samples were indented by diamond Berkovich indenter in sub microns for the nano hardness test. The Vickers micro hardness test was performed using a Wilson Wolpert Vickers micro hardness machine. The results showed that the value of hardness is increasing with the increasing length of the horn. The hardness increased from the skull to the middle of the horn length and starts decreasing gradually to the tip of the horn. Both tests confirmed that the hardness value is approximately higher at the middle of the horn. The range of hardness values of sample A, B, C, D and E obtained using nanoindentation results are 0.24-0.32 GPa, 0.24-0.28
The frictional behaviour of three different nano-composites such as 1.5 wt %, 2.0 wt % and 2.5 wt... more The frictional behaviour of three different nano-composites such as 1.5 wt %, 2.0 wt % and 2.5 wt % CNT Al nano-composite materials developed by powder metallurgy process has been studied with pin-on-disc tribometer, sliding against AISI52100 steel disc. The tribological properties of pure aluminium and carbon nanotube reinforced aluminium nano-composite were investigated and compared in this current study. Experiments were conducted using different sliding velocities of 0.5, 0.65 and 0.8 m/s and a normal load of 5, 7.5 and 10 N. Variations of coefficient of friction with the duration of rubbing at different normal loads and sliding velocities are investigated. It was revealed from the results that, coefficient of friction varies with the duration of rubbing, normal load and sliding velocities. It was clearly observed that, coefficient of friction increases for a certain duration of rubbing and after that it remains constant for the rest of the experimental time. Furthermore, the r...
There is a growing interest for novel materials of dissimilar metals due to higher requirements n... more There is a growing interest for novel materials of dissimilar metals due to higher requirements needed for some critical engineering applications. In this research, different dissimilar weld joints of high strength low alloy (HSLA) and 316 austenitic stainless steel grades were successfully produced using shielded metal arc welding (SMAW) process with 316L-16 and E7018 electrodes. Five variations of welding currents were employed within the specified range of each electrode. Other welding parameters such as heat inputs, welding speeds, weld sizes, arc voltages and time of welding were also varied. Specimens for different weld joint samples were subjected to microstructural studies using optical and scanning electron microscopes. The impact toughness test was also conducted on the samples using Izod impact testing machine. The analysis of the weld microstructures indicated the presence of type A and AF solidification patterns of austenitic stainless steels. The results further showed...
In this study 10 soil and 11 ground water samples were randomly collected, and the 222Rn concentr... more In this study 10 soil and 11 ground water samples were randomly collected, and the 222Rn concentrations were measured using a DURRIDGE RAD7 electronic radon detector. The radon concentration in ground water ranged from 0.53 BqL-1 to 5.13 BqL-1 with a mean value 2.37 BqL-1. The results show that all the groundwater samples collected have 222Rn concentrations below the US EPA Maximum Contaminant Level (MCL) of 11.1 BqL–1 (for states without radon monitoring policy and enhanced indoor air programs). All the ground water samples also have 222Rn concentrations below MCL of 100 BqL–1 recommended by EU. The annual effective dose due to ingestion (Hing) of 222Rn in the groundwater ranged from 0.00386 – 0.03744 mSvyear-1 with a mean value of 0.01706 mSvyear-1. These values are within the ICRP recommended reference level of 1 mSvy–1 for the intake of the radionuclide in water by the general public for a prolonged exposure. The effective radium content, radon mass exhalation rate and alpha ind...
Asian Journal of Engineering and Technology, Apr 25, 2014
The current paper study the hardness behaviour of Kano cattle horn under nanoindentation and micr... more The current paper study the hardness behaviour of Kano cattle horn under nanoindentation and micro hardness tests. Five different samples were generated and level A, B, C, D and E cut along the whole length of the horn from the skull to the tip respectively. The samples were indented by diamond Berkovich indenter in sub microns for the nano hardness test. The Vickers micro hardness test was performed using a Wilson Wolpert Vickers micro hardness machine. The results showed that the value of hardness is increasing with the increasing length of the horn. The hardness increased from the skull to the middle of the horn length and starts decreasing gradually to the tip of the horn. Both tests confirmed that the hardness value is approximately higher at the middle of the horn. The range of hardness values of sample A, B, C, D and E obtained using nanoindentation results are 0
The dispersion quality is the major concern in nanocomposite development as it determines the hom... more The dispersion quality is the major concern in nanocomposite development as it determines the homogeneity of the enhanced mechanical and tribological properties of the composite. This work study the morphology of aluminium powder in the CNTs-Al nanocomposite prepared with different weight percentage of CNT in aluminium matrix using powder metallurgy route under high energy planetary ball milling operations at varying time and speed of milling of 2, 3hrs and 250, 300 rpm respectively. The preliminary mixing of CNTs and aluminium powder in a tube via manual shaking and the speed used could be the main contributing factor in achieving uniform dispersion of CNT in aluminium matrix within short time. Evidence of FESEM morphology with significant reduction of milling time confirmed that CNT was homogeneously dispersed and distributed into Al matrix.Key words: Milling parameter, CNT-Al nanocomposite, Homogenous dispersion
Titanium (Ti-6Al-4V) alloy is very attractive for many applications due to its high strength-to-w... more Titanium (Ti-6Al-4V) alloy is very attractive for many applications due to its high strength-to-weight ratio and high corrosion resistance. Even then, with these attractive properties, it has poor shear strength and surface wear properties. This study is therefore undertaken to investigate the effect of sliding parameters on the surface wear behavior of Ti-6Al-4V alloy. Pin-like specimens of the alloy were produced and subjected to sliding motion on a pin-on-disk apparatus using different speeds, loads and sliding distances. The surface and specific wear rates of the alloy were evaluated as the main output of the study. Results indicate that the most severe surface wear rate of over 0.008 mm3/sec is experienced under conditions of low disk speed (50 rpm) with high input weight (46.5 N). Higher sliding distance is also found to affect the severity of the surface wear rate. All results of specific wear rates evaluated indicate that Ti-6Al-4V alloy can be classified as a low surface we...
Research works are being done to substitute heavy material with a suitable lighter weight and che... more Research works are being done to substitute heavy material with a suitable lighter weight and cheaper material which has better properties for this particular application. Processing route plays a significant role in developing the material for any application with effective cost and environmental factors and careful selection of processing route is especially very important for brake disc material. In this paper, a comprehensive review has been done on material and processing route in view of selecting alternative lightweight and cheaper materials for aircraft brake disc application. The advantages and disadvantages between aluminium metal matrix composite and other materials as well as the advantages of powder metallurgy route with other processes are presented for better understanding of the materials and process selection. Finally, emphasis has given on lightweight and cheaper carbon nanotube aluminium matrix (CNT-Al) nano-composite material with specific processing route as a case study. This is mainly based on material selection using material selection process which showed CNT-Al as an excellent candidate material for brake disc application.
Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, ... more Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.
International Journal of Engineering Materials and Manufacture
The effect of heat treatment on welded joints using the shielded metal arc welding (SMAW) on thre... more The effect of heat treatment on welded joints using the shielded metal arc welding (SMAW) on three different types of steel with different carbon ratios under constant conditions such as the welding current 120A, voltage 80V, Diameter 10 mm and angle 60 degree. Hardness tests chemical composition analysis were carried out and it was observed that, high carbon steel has the highest hardness of about 459 on maximum HV value, followed by the low carbon steel with the hardness of 316HV maximum and medium carbon experience the least value of 208HV. Hardness increases with low carbon content as shown in the experimental results which deduced that the low carbon steel used was confirmed to be the high-strength-low-alloy steel of grade 8620-HSLA-Nickel-Chromium-Molybdenum steel. The microstructure of the base metal was analysed before heating to support the results of chemical analysis. Nickel percentage of up to 0.147% and Chromium 0.083%. Molybdenum was just 0.030% which contributed in af...
The paper studied the microstructure of cattle horn using scanning electron microscope (SEM) to s... more The paper studied the microstructure of cattle horn using scanning electron microscope (SEM) to study its bonding nature. Five different samples were generated and level A, B, C, D and E cut along the whole length of the horn from the skull to the tip respectively. The samples were accordingly cut to round shapes to a diameter of 15.0mm to suit the mounting position and smoothened for easy passage of the rays. The thickness of specimen is 2.0mm. Samples are grinded directly using emery paper with grit size as follows: 180, 240, 320, 400, 600, 800, 1200 and 1500. After grinding, the samples are subjected to polishing using alumina solution of 0.5 followed by 0.3 particle size. From the morphology of the five samples analysed using SEM it was found the horn has an interesting natural structure arrange in a form of layers in a wave like form which varies from sharp to narrow width of the wave like structure and later flat from the tip of the horn to the skull. And the layers are unifor...
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