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V Balasubramanian - One of the best experts on this subject based on the ideXlab platform.
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Influence of Tool Tilt Angle on the Formation of Friction Stir Processing Zone in Cast Magnesium Alloy ZK60/SiCp Surface Composites
Metallography Microstructure and Analysis, 2019Co-Authors: M Vigneshkumar, G Padmanaban, V BalasubramanianAbstract:Cast ZK60 magnesium alloy has significant beneficial properties including high strength-to-weight ratio. Poor surface properties such as low friction and wear resistance restrict the use of this alloy in structural applications. Therefore, it is very much essential to adopt surface engineering to enhance this alloy’s surface properties. Friction stir Processing is one of the potential thermo-mechanical Processing techniques that alters the microstructural and tribological properties of the material. In the present study, ZK60/SiCp was fabricated by means of FSP. Tool tilt angle is a critical process parameter which influences the material flow, and particle breakup and distribution in the processed Zone. In this work, an attempt has been made to understand the effects of tool tilt angle (ranges 0°–4°) on the grain refinement of matrix and the distribution of SiC particles. It is shown that the FSPed materials Zone produced using the tilt angle 2° exhibited higher hardness (125 Hv); this was attributed to the optimization of heat generation, material flow, grain boundary strengthening, and homogeneous particle distribution.
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influence of tool tilt angle on the formation of friction stir Processing Zone in cast magnesium alloy zk60 sicp surface composites
Metallography Microstructure and Analysis, 2019Co-Authors: G Padmanaban, M Vigneshkumar, V BalasubramanianAbstract:Cast ZK60 magnesium alloy has significant beneficial properties including high strength-to-weight ratio. Poor surface properties such as low friction and wear resistance restrict the use of this alloy in structural applications. Therefore, it is very much essential to adopt surface engineering to enhance this alloy’s surface properties. Friction stir Processing is one of the potential thermo-mechanical Processing techniques that alters the microstructural and tribological properties of the material. In the present study, ZK60/SiCp was fabricated by means of FSP. Tool tilt angle is a critical process parameter which influences the material flow, and particle breakup and distribution in the processed Zone. In this work, an attempt has been made to understand the effects of tool tilt angle (ranges 0°–4°) on the grain refinement of matrix and the distribution of SiC particles. It is shown that the FSPed materials Zone produced using the tilt angle 2° exhibited higher hardness (125 Hv); this was attributed to the optimization of heat generation, material flow, grain boundary strengthening, and homogeneous particle distribution.
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influence of tool rotational speed on the formation of friction stir Processing Zone in cast zk60 sicp magnesium alloy surface composites
Materials Performance and Characterization, 2018Co-Authors: M Vigneshkumar, G Padmanaban, V BalasubramanianAbstract:A Cast ZK60 magnesium alloy plays a tremendous role in the fabrication of lightweight structural materials. However, the low surface properties, like low friction and wear resistance, restricts the magnesium alloy during the structural application. Conventionally, the surface properties of magnesium alloys were improved using various Processing methods like high-energy electron beam irradiation, plasma-transferred arc surfacing, and high-energy laser melt treatment. However, the above processes are involved in melting the magnesium material, which results in defects and detrimental metallurgical phase formation. Friction Stir Processing (FSP) can overcome this problem since the Processing is done in the solid state. However, FSP often appears to be a significant applicant on the magnesium plate to attain successful fabrication of surface metal matrix composites. In this investigation, an attempt at FSP Zone formation in magnesium alloy has been made in order to understand the influences of rotational speeds ranging from 700 to 1,100 r/min. From this investigation, it is found that the FSP made by using the high tool rotational speed of 900 r/min and 10 mm/min exhibited higher hardness and uniform particle distribution. This may be attributed to the grain boundary and dispersion strengthening.
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Influences of tool pin profile and axial force on the formation of friction stir Processing Zone in AA6061 aluminium alloy
The International Journal of Advanced Manufacturing Technology, 2008Co-Authors: K. Elangovan, V Balasubramanian, M. ValliappanAbstract:AA6061 aluminium alloy (Al-Mg-Si alloy) has gathered wide acceptance in the fabrication of light weight structures requiring a high strength-to-weight ratio and good corrosion resistance. Compared to the fusion welding processes that are routinely used for joining structural aluminium alloys, the friction stir welding (FSW) process is an emerging solid state joining process in which the material that is being welded does not melt and recast. This process uses a non-consumable tool to generate frictional heat in the abutting surfaces. The welding parameters such as tool rotational speed, welding speed, axial force etc., and the tool pin profile plays a major role in deciding the weld quality. In this investigation an attempt has been made to understand the effect of axial force and tool pin profiles on FSP Zone formation in AA6061 aluminium alloy. Five different tool pin profiles (straight cylindrical, tapered cylindrical, threaded cylindrical, triangular and square) have been used to fabricate the joints at three different axial force levels. The formation of FSP Zone has been analysed macroscopically. Tensile properties of the joints have been evaluated and correlated with the FSP Zone formation. From this investigation it is found that the square tool pin profile produces mechanically sound and metallurgically defect free welds compared to other tool pin profiles.
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influences of tool pin profile and welding speed on the formation of friction stir Processing Zone in aa2219 aluminium alloy
Journal of Materials Processing Technology, 2008Co-Authors: K. Elangovan, V BalasubramanianAbstract:AA2219 aluminium alloy has gathered wide acceptance in the fabrication of light weight structures requiring a high strength to weight ratio. Compared to the fusion welding processes that are routinely used for joining structural aluminium alloys, friction stir welding (FSW) process is an emerging solid state joining process in which the material that is being welded does not melt and recast. This process uses a non-consumable tool to generate frictional heat in the abutting surfaces. The welding parameters and tool pin profile play major roles in deciding the weld quality. In this investigation, an attempt has been made to understand the effect of welding speed and tool pin profile on FSP Zone formation in AA2219 aluminium alloy. Five different tool pin profiles (straight cylindrical, tapered cylindrical, threaded cylindrical, triangular and square) have been used to fabricate the joints at three different welding speeds. The formation of FSP Zone has been analysed macroscopically. Tensile properties of the joints have been evaluated and correlated with the FSP Zone formation. From this investigation it is found that the square pin profiled tool produces mechanically sound and metallurgically defect free welds compared to other tool pin profiles.
K. Elangovan - One of the best experts on this subject based on the ideXlab platform.
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Influences of tool pin profile and axial force on the formation of friction stir Processing Zone in AA6061 aluminium alloy
The International Journal of Advanced Manufacturing Technology, 2008Co-Authors: K. Elangovan, V Balasubramanian, M. ValliappanAbstract:AA6061 aluminium alloy (Al-Mg-Si alloy) has gathered wide acceptance in the fabrication of light weight structures requiring a high strength-to-weight ratio and good corrosion resistance. Compared to the fusion welding processes that are routinely used for joining structural aluminium alloys, the friction stir welding (FSW) process is an emerging solid state joining process in which the material that is being welded does not melt and recast. This process uses a non-consumable tool to generate frictional heat in the abutting surfaces. The welding parameters such as tool rotational speed, welding speed, axial force etc., and the tool pin profile plays a major role in deciding the weld quality. In this investigation an attempt has been made to understand the effect of axial force and tool pin profiles on FSP Zone formation in AA6061 aluminium alloy. Five different tool pin profiles (straight cylindrical, tapered cylindrical, threaded cylindrical, triangular and square) have been used to fabricate the joints at three different axial force levels. The formation of FSP Zone has been analysed macroscopically. Tensile properties of the joints have been evaluated and correlated with the FSP Zone formation. From this investigation it is found that the square tool pin profile produces mechanically sound and metallurgically defect free welds compared to other tool pin profiles.
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influences of tool pin profile and welding speed on the formation of friction stir Processing Zone in aa2219 aluminium alloy
Journal of Materials Processing Technology, 2008Co-Authors: K. Elangovan, V BalasubramanianAbstract:AA2219 aluminium alloy has gathered wide acceptance in the fabrication of light weight structures requiring a high strength to weight ratio. Compared to the fusion welding processes that are routinely used for joining structural aluminium alloys, friction stir welding (FSW) process is an emerging solid state joining process in which the material that is being welded does not melt and recast. This process uses a non-consumable tool to generate frictional heat in the abutting surfaces. The welding parameters and tool pin profile play major roles in deciding the weld quality. In this investigation, an attempt has been made to understand the effect of welding speed and tool pin profile on FSP Zone formation in AA2219 aluminium alloy. Five different tool pin profiles (straight cylindrical, tapered cylindrical, threaded cylindrical, triangular and square) have been used to fabricate the joints at three different welding speeds. The formation of FSP Zone has been analysed macroscopically. Tensile properties of the joints have been evaluated and correlated with the FSP Zone formation. From this investigation it is found that the square pin profiled tool produces mechanically sound and metallurgically defect free welds compared to other tool pin profiles.
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influences of tool pin profile and tool shoulder diameter on the formation of friction stir Processing Zone in aa6061 aluminium alloy
Materials & Design, 2008Co-Authors: K. Elangovan, V BalasubramanianAbstract:Abstract AA6061 aluminium alloy (Al–Mg–Si alloy) has gathered wide acceptance in the fabrication of light weight structures requiring a high strength-to-weight ratio and good corrosion resistance. Compared to the fusion welding processes that are routinely used for joining structural aluminium alloys, friction stir welding (FSW) process is an emerging solid state joining process in which the material that is being welded does not melt and recast. This process uses a non-consumable tool to generate frictional heat in the abutting surfaces. The welding parameters such as tool rotational speed, welding speed, axial force, etc., and tool pin profile play a major role in deciding the weld quality. In this investigation an attempt has been made to understand the effect of tool pin profile and tool shoulder diameter on FSP Zone formation in AA6061 aluminium alloy. Five different tool pin profiles (straight cylindrical, tapered cylindrical, threaded cylindrical, triangular and square) with three different shoulder diameters have been used to fabricate the joints. The formation of FSP Zone has been analysed macroscopically. Tensile properties of the joints have been evaluated and correlated with the FSP Zone formation. From this investigation it is found that the square pin profiled tool with 18 mm shoulder diameter produced mechanically sound and metallurgically defect free welds compared to other tool pin profiles.
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influences of pin profile and rotational speed of the tool on the formation of friction stir Processing Zone in aa2219 aluminium alloy
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2007Co-Authors: K. Elangovan, V BalasubramanianAbstract:AA2219 aluminium alloy has gathered wide acceptance in the fabrication of light weight structures requiring a high strength-to-weight ratio. Compared to the many fusion welding processes that are routinely used for joining structural aluminium alloys, friction stir welding (FSW) process is an emerging solid state joining process in which the material that is being welded does not melt and recast. The welding parameters and tool pin profile play a major role in deciding the weld quality. In this investigation an attempt has been made to understand the influences of rotational speed and pin profile of the tool on friction stir processed (FSP) Zone formation in AA2219 aluminium alloy. Five different tool pin profiles (straight cylindrical, tapered cylindrical, threaded cylindrical, triangular and square) have been used to fabricate the joints at three different tool rotational speeds. The formation of FSP Zone has been analysed macroscopically. Tensile properties of the joints have been evaluated and correlated with the FSP Zone formation. From this investigation it is found that the square tool pin profile produces mechanically sound and metallurgically defect free welds compared to other tool pin profiles.
Safiur M Rahman - One of the best experts on this subject based on the ideXlab platform.
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multivariate statistical analysis of metal contamination in surface water around dhaka export Processing industrial Zone bangladesh
Environmental Nanotechnology Monitoring and Management, 2018Co-Authors: Narottam Saha, Safiur M RahmanAbstract:Deterioration of water quality by anthropogenic heavy metal pollution is a critical issue, especially in the least developed countries. This study, therefore, utilizes multivariate statistical approaches to report on the sources of heavy metals contamination in water bodies close to Dhaka Export Processing Zone industrial area in Bangladesh. Correlation matrix showed a number of significant associations (p < 0.01 and p < 0.05) among the metals, with no major seasonal influence on metal associations. Spatial variability of metal concentrations, however, was observed with lowering of concentration as distance increased from the pollution sources. Principal component and cluster analysis identified three major sources of metal pollution including untreated industrial effluents, municipal wastes, and atmospheric deposition of metals from burning of fossil fuels. These three sources were responsible for the data structure explaining 79.97% of total variance. Hierarchical cluster analysis demonstrated three clusters of nine sampling stations depending on the similarity of the data. Overall, the levels of metal concentrations determined in this study clearly illustrated the anthropogenic disturbances on water quality.
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industrial metal pollution in water and probabilistic assessment of human health risk
Journal of Environmental Management, 2017Co-Authors: Narottam Saha, Safiur M Rahman, Mohammad Boshir Ahmed, John L ZhouAbstract:Abstract Concentration of eight heavy metals in surface and groundwater around Dhaka Export Processing Zone (DEPZ) industrial area were investigated, and the health risk posed to local children and adult residents via ingestion and dermal contact was evaluated using deterministic and probabilistic approaches. Metal concentrations (except Cu, Mn, Ni, and Zn) in Bangshi River water were above the drinking water quality guidelines, while in groundwater were less than the recommended limits. Concentration of metals in surface water decreased as a function of distance. Estimations of non-carcinogenic health risk for surface water revealed that mean hazard index (HI) values of As, Cr, Cu, and Pb for combined pathways (i.e., ingestion and dermal contact) were >1.0 for both age groups. The estimated risk mainly came from the ingestion pathway. However, the HI values for all the examined metals in groundwater were −4 for adult and children. Although, probabilistically estimated 95th percentile values of TCR exceeded the benchmark, mean TCR values were less than 1 × 10 −4 . Simulated results showed that 20.13% and 5.43% values of TCR for surface water were >1 × 10 −4 for adult and children, respectively. Deterministic and probabilistic estimations of cancer risk through exposure to groundwater were well below the safety limit. Overall, the population exposed to Bangshi River water remained at carcinogenic and non-carcinogenic health threat and the risk was higher for adults. Sensitivity analysis identified exposure duration (ED) and ingestion rate (IR) of water as the most relevant variables affecting the probabilistic risk estimation model outcome.
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potential ecological risk assessment of heavy metal contamination in sediment and water body around dhaka export Processing Zone bangladesh
Environmental Earth Sciences, 2014Co-Authors: Safiur M Rahman, Narottam Saha, Hossain A MollaAbstract:Sediments and surface water contamination by the industrial effluents containing heavy metals is the most detrimental environmental impact. Therefore, the present work attempts to determine the status of eight heavy metal distribution in sediments and water samples, and their ecological risks’ assessment in the studied area. The distribution pattern of heavy metals in the water and sediment follows the sequences: Zn > Cu > Pb > Cr > Mn > Ni > As > Cd and Mn > Zn > Cr > Pb > Cu > Ni > As > Cd, respectively. Gross water pollution is observed at different sampling points of Dhalai Beel and Bangshi River. The comparison of sedimentary mean metal concentrations with several environmental contamination monitoring parameters, viz, threshold effect level (TEL), probable effect level (PEL), and severe effect lever (SEL) indicates that the metal levels are less than PEL except Cr. Moreover, the level of contamination degree (Cd) and modified degree of contamination (mCd) indicates ‘low’ and ‘nil to low’ degree of contamination, respectively. Pollution load indices (PLI) of the studied area are lower than unity, indicates no pollution. Furthermore, a toxic-response factor is applied to assess the potential ecological risk of these heavy metals into the water body. The results of this study exhibit a low potential ecological risk of heavy metals. The Pearson’s correlation and cluster analysis are also performed to assess the heavy metal interactions in water and sediment samples.
Narottam Saha - One of the best experts on this subject based on the ideXlab platform.
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multivariate statistical analysis of metal contamination in surface water around dhaka export Processing industrial Zone bangladesh
Environmental Nanotechnology Monitoring and Management, 2018Co-Authors: Narottam Saha, Safiur M RahmanAbstract:Deterioration of water quality by anthropogenic heavy metal pollution is a critical issue, especially in the least developed countries. This study, therefore, utilizes multivariate statistical approaches to report on the sources of heavy metals contamination in water bodies close to Dhaka Export Processing Zone industrial area in Bangladesh. Correlation matrix showed a number of significant associations (p < 0.01 and p < 0.05) among the metals, with no major seasonal influence on metal associations. Spatial variability of metal concentrations, however, was observed with lowering of concentration as distance increased from the pollution sources. Principal component and cluster analysis identified three major sources of metal pollution including untreated industrial effluents, municipal wastes, and atmospheric deposition of metals from burning of fossil fuels. These three sources were responsible for the data structure explaining 79.97% of total variance. Hierarchical cluster analysis demonstrated three clusters of nine sampling stations depending on the similarity of the data. Overall, the levels of metal concentrations determined in this study clearly illustrated the anthropogenic disturbances on water quality.
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industrial metal pollution in water and probabilistic assessment of human health risk
Journal of Environmental Management, 2017Co-Authors: Narottam Saha, Safiur M Rahman, Mohammad Boshir Ahmed, John L ZhouAbstract:Abstract Concentration of eight heavy metals in surface and groundwater around Dhaka Export Processing Zone (DEPZ) industrial area were investigated, and the health risk posed to local children and adult residents via ingestion and dermal contact was evaluated using deterministic and probabilistic approaches. Metal concentrations (except Cu, Mn, Ni, and Zn) in Bangshi River water were above the drinking water quality guidelines, while in groundwater were less than the recommended limits. Concentration of metals in surface water decreased as a function of distance. Estimations of non-carcinogenic health risk for surface water revealed that mean hazard index (HI) values of As, Cr, Cu, and Pb for combined pathways (i.e., ingestion and dermal contact) were >1.0 for both age groups. The estimated risk mainly came from the ingestion pathway. However, the HI values for all the examined metals in groundwater were −4 for adult and children. Although, probabilistically estimated 95th percentile values of TCR exceeded the benchmark, mean TCR values were less than 1 × 10 −4 . Simulated results showed that 20.13% and 5.43% values of TCR for surface water were >1 × 10 −4 for adult and children, respectively. Deterministic and probabilistic estimations of cancer risk through exposure to groundwater were well below the safety limit. Overall, the population exposed to Bangshi River water remained at carcinogenic and non-carcinogenic health threat and the risk was higher for adults. Sensitivity analysis identified exposure duration (ED) and ingestion rate (IR) of water as the most relevant variables affecting the probabilistic risk estimation model outcome.
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potential ecological risk assessment of heavy metal contamination in sediment and water body around dhaka export Processing Zone bangladesh
Environmental Earth Sciences, 2014Co-Authors: Safiur M Rahman, Narottam Saha, Hossain A MollaAbstract:Sediments and surface water contamination by the industrial effluents containing heavy metals is the most detrimental environmental impact. Therefore, the present work attempts to determine the status of eight heavy metal distribution in sediments and water samples, and their ecological risks’ assessment in the studied area. The distribution pattern of heavy metals in the water and sediment follows the sequences: Zn > Cu > Pb > Cr > Mn > Ni > As > Cd and Mn > Zn > Cr > Pb > Cu > Ni > As > Cd, respectively. Gross water pollution is observed at different sampling points of Dhalai Beel and Bangshi River. The comparison of sedimentary mean metal concentrations with several environmental contamination monitoring parameters, viz, threshold effect level (TEL), probable effect level (PEL), and severe effect lever (SEL) indicates that the metal levels are less than PEL except Cr. Moreover, the level of contamination degree (Cd) and modified degree of contamination (mCd) indicates ‘low’ and ‘nil to low’ degree of contamination, respectively. Pollution load indices (PLI) of the studied area are lower than unity, indicates no pollution. Furthermore, a toxic-response factor is applied to assess the potential ecological risk of these heavy metals into the water body. The results of this study exhibit a low potential ecological risk of heavy metals. The Pearson’s correlation and cluster analysis are also performed to assess the heavy metal interactions in water and sediment samples.
M Vigneshkumar - One of the best experts on this subject based on the ideXlab platform.
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Influence of Tool Tilt Angle on the Formation of Friction Stir Processing Zone in Cast Magnesium Alloy ZK60/SiCp Surface Composites
Metallography Microstructure and Analysis, 2019Co-Authors: M Vigneshkumar, G Padmanaban, V BalasubramanianAbstract:Cast ZK60 magnesium alloy has significant beneficial properties including high strength-to-weight ratio. Poor surface properties such as low friction and wear resistance restrict the use of this alloy in structural applications. Therefore, it is very much essential to adopt surface engineering to enhance this alloy’s surface properties. Friction stir Processing is one of the potential thermo-mechanical Processing techniques that alters the microstructural and tribological properties of the material. In the present study, ZK60/SiCp was fabricated by means of FSP. Tool tilt angle is a critical process parameter which influences the material flow, and particle breakup and distribution in the processed Zone. In this work, an attempt has been made to understand the effects of tool tilt angle (ranges 0°–4°) on the grain refinement of matrix and the distribution of SiC particles. It is shown that the FSPed materials Zone produced using the tilt angle 2° exhibited higher hardness (125 Hv); this was attributed to the optimization of heat generation, material flow, grain boundary strengthening, and homogeneous particle distribution.
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influence of tool tilt angle on the formation of friction stir Processing Zone in cast magnesium alloy zk60 sicp surface composites
Metallography Microstructure and Analysis, 2019Co-Authors: G Padmanaban, M Vigneshkumar, V BalasubramanianAbstract:Cast ZK60 magnesium alloy has significant beneficial properties including high strength-to-weight ratio. Poor surface properties such as low friction and wear resistance restrict the use of this alloy in structural applications. Therefore, it is very much essential to adopt surface engineering to enhance this alloy’s surface properties. Friction stir Processing is one of the potential thermo-mechanical Processing techniques that alters the microstructural and tribological properties of the material. In the present study, ZK60/SiCp was fabricated by means of FSP. Tool tilt angle is a critical process parameter which influences the material flow, and particle breakup and distribution in the processed Zone. In this work, an attempt has been made to understand the effects of tool tilt angle (ranges 0°–4°) on the grain refinement of matrix and the distribution of SiC particles. It is shown that the FSPed materials Zone produced using the tilt angle 2° exhibited higher hardness (125 Hv); this was attributed to the optimization of heat generation, material flow, grain boundary strengthening, and homogeneous particle distribution.
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influence of tool rotational speed on the formation of friction stir Processing Zone in cast zk60 sicp magnesium alloy surface composites
Materials Performance and Characterization, 2018Co-Authors: M Vigneshkumar, G Padmanaban, V BalasubramanianAbstract:A Cast ZK60 magnesium alloy plays a tremendous role in the fabrication of lightweight structural materials. However, the low surface properties, like low friction and wear resistance, restricts the magnesium alloy during the structural application. Conventionally, the surface properties of magnesium alloys were improved using various Processing methods like high-energy electron beam irradiation, plasma-transferred arc surfacing, and high-energy laser melt treatment. However, the above processes are involved in melting the magnesium material, which results in defects and detrimental metallurgical phase formation. Friction Stir Processing (FSP) can overcome this problem since the Processing is done in the solid state. However, FSP often appears to be a significant applicant on the magnesium plate to attain successful fabrication of surface metal matrix composites. In this investigation, an attempt at FSP Zone formation in magnesium alloy has been made in order to understand the influences of rotational speeds ranging from 700 to 1,100 r/min. From this investigation, it is found that the FSP made by using the high tool rotational speed of 900 r/min and 10 mm/min exhibited higher hardness and uniform particle distribution. This may be attributed to the grain boundary and dispersion strengthening.