Because of the increasing awareness of the environment and energy issues, as well as advances in ... more Because of the increasing awareness of the environment and energy issues, as well as advances in technology, the areas of application for annual plant fiber functional materials are expanding. In this work, two chemical treatments, alkalization (2 h agitation with 5% NaOH) and furfurylation (graft furfuryl alcohol followed by oxidation with (1N) NaClO 2 solution), were conducted on Luffa cylindrica fiber surfaces. The grafting of furfuryl alcohol followed by oxidation-generated quinines showed better results than alkaline treatment with respect to enhancement of surface area and hydrophobicity as well as wax, lignin, and hemicellulose extraction. The efficiency of chemical treatments was verified by elemental analysis and FTIR spectroscopy. Differential scanning calorimetry, thermo-gravimetric analysis, scanning electron microscopy, water absorption, and mechanical tests were performed to determine the thermal, mechanical, and morphological properties of untreated and chemically treated luffa fiber reinforced epoxy composites. Microstructures of the composites were examined to determine the mechanisms for the fiber-matrix interaction, which affects the thermal stability, water absorption, and mechanical behavior of the composites. The data from the water absorption process of composites at various temperatures were analyzed using a diffusion model based on Fick's law.
There is a long demand for light-weight, high-strength, and wear-resistance aluminium alloys, par... more There is a long demand for light-weight, high-strength, and wear-resistance aluminium alloys, particularly in automotive and aerospace industries. This demand is somewhat fulfilled by aluminium metal matrix composites. However, aluminium nano-metal matrix composite because of its superior properties is increasingly popular to replace aluminium metal matrix composites. The SiC (grit size is <90 nm) with purity 99.9% nanoparticle can enhance the properties of the base material in terms of tensile strength, hardness, microhardness, and mechanical strength. Pure Al (99.9%) matrix composites reinforced with SiC (purity 99.9%) nanoparticles are fabricated by liquid-state method with 1 wt% Mg, and their microstructure, mechanical properties (wear resistance, tensile behaviour, hardness), XRD, SEM were investigated. Here pure SiC purity 99.9% added into molten Al with 1 wt% Mg using squeeze die casting with furnace temperature 850 °C and pathway temperature 700 °C and for uniform mixing of SiC nanoparticles into matrix use stir method with 400 rpm for 2 min and pressure was 31.3 mpa. Pure Al and 1 wt% SiC nanocomposites with 1 wt% Mg were developed; the Al-SiC nanocomposites were characterised using scanning electron microscope (SEM) and X-ray diffraction (XRD). Due to used higher pressure during solidification, there is very low porosity. Stir is used before mixing the nano-SiC particle and pouring the metal into mould, which gives the uniform distribution of nanoparticles into matrix.
Advances in intelligent systems and computing, Nov 9, 2016
In continuous casting of steel, liquid steel is continuously solidified into a finished product. ... more In continuous casting of steel, liquid steel is continuously solidified into a finished product. Bokaro Steel Limited have slab caster and during continuous casting, one of the major operational irregularities encountered is breakout. A breakout is a hazard whereby the thin shell of the strand breaks, allowing the still-molten metal inside the strand to leak out from the mould, thus necessitating an expensive machine shutdown. Hence the breakout has a profound influence on the caster availability; affecting the productivity, cost of production, damage of machinery, safety hazards, etc. Breakouts occur due to the presence of a primary crack before solidification of liquid steel. Controlling the primary cracks lead to reduce chances of breakouts. Breakout prediction system of Bokaro Steel Limited uses only thermocouples temperature as an input of logic based algorithm controlled by strand PLC to predict breakout and generate alarm. This system sometimes generates lots of false alarm and sometimes even fails to generate an alarm before breakout. In this paper, two back-propagation neural networks are developed to predict the presence of primary crack that might lead to breakout of liquid steel. One is neural network1 train only with one input parameter (temperatures of thermocouples attached to the mould) and the other is neural network2 train with three input parameters (temperatures of thermocouples, casting speed and mould level). Both the neural network1 and network2 have only one output. Output of neural networks is either 0 for no alarm (no primary crack) or 1 for alarm (presence of primary crack) in breakout conditions. Comparison of the network1 with network2 showed that network2 has less output error, better performance and identifies primary crack more accurately. Performance of neural networks are done using Levenberg–Marquardt training algorithm, and also log sigmoid transfer function is used for both the hidden and output layer. The neural networks model training, validation and testing is done by simulating in Mat-Lab/Simulink.
Mold breakout is one of the significant problems in a continuous casting machine (caster). It rep... more Mold breakout is one of the significant problems in a continuous casting machine (caster). It represents one of the key areas within the steel production facilities of a steel plant. A breakout event on a caster will always cause safety hazards, high repair costs, loss of production, and shutdown of the caster for a short while. In this paper, a logic-judgment-based mold breakout prediction system has been developed for a continuous casting machine. This system developed new algorithms to detect the different sticker behaviors. With more algorithms running, each algorithm is more specialized in the other behaviors of stickers. This new logic-based breakout prediction system (BOPS) not only detects sticker breakouts but also detects breakouts that takes place due to variations in casting speed, mold level fluctuation, and taper/mold problems. This system also finds the exact location of the breakout in the mold and reduces the number of false alarms. The task of the system is to reco...
Metal foams are known to exhibit multifunctional behavior. It can offer a unique combination of s... more Metal foams are known to exhibit multifunctional behavior. It can offer a unique combination of several properties that cannot be achieved by one conventional material at the same time e.g. ultra-low density, high stiffness and capability to absorb crash energy, and excellent sound absorption properties. These unique combinations of properties indicate its various potential applications such as ultra light structures, in impact/blast absorption systems, and for sound absorption etc. Metal foam is a generic term for a class of material, which can be classified in terms of their structures, processing routes, and base metal. The main aim of this research work is to produce low cost, low-density aluminum foams by indigenously designed and fabricated equipment. This aluminum foam material possess all the positive attributes realized in current metal foam technology, such as high specific stiffness, low relative density, and high-energy absorption capacity. This material is designed to r...
Aluminium foams, which may replace all the energy absorbing materials in near future, are produce... more Aluminium foams, which may replace all the energy absorbing materials in near future, are produced by melting Aluminium alloy (LM6) containing blowing agent(s) and with continuous stirring of the melt. TiH2 is a known blowing agent for this. As TiH2 begins to decompose into Ti and gaseous H2 when heated above about 738K (465°C), large volumes of hydrogen gas are rapidly produced, creating bubbles that leads to manufacture of closed cell foam. Cellular materials like this produced foams has to be machined into pieces with desired shape for further investigation. In order to define the Compressive and impact properties of this material, LS-DYNA modeling and crashing simulation, which uniquely defines the mechanical behavior of this modified Al-MMC foam has been discussed in details.
Advances in Civil and Industrial Engineering, 2020
Additive manufacturing (AM) has developed and gained popularity across the globe into a multi-bil... more Additive manufacturing (AM) has developed and gained popularity across the globe into a multi-billion-dollar industry that involves many materials and techniques. AM has created itself as a technology for the manufacturing of metallic parts with enhanced mechanical characteristics that are scientifically sound and commercially feasible. However, there are various challenges, from business point of view, like high machine and material costs. Considering the complexities involved, sustainable manufacturing, optimization tools, and simulation models are necessary in order to save time and costly trial and errors. Topology optimization and simulation of AM processes are commercially available and are receiving attention from scientists and industry. Thus, this chapter is designed to provide readers with a brief introduction to AM technologies with typical applications. The main objective of this chapter is to provide the current trends and innovations in the field of design for additive...
Sustainable Engineering Products and Manufacturing Technologies, 2019
Abstract Semisolid metal processing (SSMP) is a novel metal forming technology which offers near ... more Abstract Semisolid metal processing (SSMP) is a novel metal forming technology which offers near net-shaped metal components of complex geometries. The present work aims to classify the currently available SSMP technologies and presents a comprehensive review of the potential mechanisms that lead to microstructural alterations during the production of feedstock material. Keeping in mind the current needs of the automobile and allied industries, the review of state-of-art research work was focused on thixoforming with an emphasis on aluminum-based alloys and composites. Focus was drawn on the two major SSMP routes: “rheo-casting” and “thixoforming.” The potential benefits and industrial applications were highlighted. Nondendritic microstructural evolution in the semisolid range and its beneficial effects is also emphasized. Considering the complexities involved in the areas of thixoforming for sustainable manufacturing, optimized solutions, are necessary. This chapter presents an overview of recent trends, and new challenges, for achieving sustainability at the product by taking Aluminum-based composites as the materials and thixoforming as the process focusing on the technology and system levels for achieving sustainability. Further, the mechanical properties of the thixoformed Al-based alloys and composites were presented and compared with gravity cast and rheo-cast conditions. Thus a critical assessment aimed at understanding the processing and structure–property relationships in the thixoformed alloys and composites in meeting the needs of the industry.
Aluminium hybrid metal matrix nano composite (AHMNC) material has all the advantages of conventio... more Aluminium hybrid metal matrix nano composite (AHMNC) material has all the advantages of conventional metal matrix nano composite with multifunctional properties because of the hybrid reinforcement. As a result, these materials offer a unique combination of properties that are not possible to achieve in conventional materials. The present study deals with the fabrication of aluminium hybrid nano composites by reinforcing Al2014 with nano sized B 4 C and graphite, processed through stir casting route followed by ultrasonic and squeeze casting. The addition of B 4 C improves the hardness, whereas Gr particles improve wear resistance in the composite. These combinations of the reinforcements are chosen for application under high abrasive conditions. Ultrasonic agitation has been done to uniformly distribute the reinforcement, whereas squeeze casting is done to reduce the porosity of the cast. The cast composite has been cut to prepare specimens for hardness, tensile strength, and microstructure as per the ASTM standards. The mechanical properties of the composite were evaluated and compared to the conventional. The microstructure of the composites was studied using optical microscopy to investigate the proper distribution of reinforcement and microstructure in the AHMNCs. The result indicates a significant improvement in the hardness. Further, the microstructure studies reveal that the reinforcement was fairly uniformly distributed over the matrix material.
Aluminium hybrid metal matrix nano composite (AHMNC) material has all the advantages of conventio... more Aluminium hybrid metal matrix nano composite (AHMNC) material has all the advantages of conventional metal matrix nano composite with multifunctional properties because of the hybrid reinforcement. As a result, these materials offer a unique combination of properties that are not possible to achieve in conventional materials. The present study deals with the fabrication of aluminium hybrid nano composites by reinforcing Al2014 with nano sized B 4 C and graphite, processed through stir casting route followed by ultrasonic and squeeze casting. The addition of B 4 C improves the hardness, whereas Gr particles improve wear resistance in the composite. These combinations of the reinforcements are chosen for application under high abrasive conditions. Ultrasonic agitation has been done to uniformly distribute the reinforcement, whereas squeeze casting is done to reduce the porosity of the cast. The cast composite has been cut to prepare specimens for hardness, tensile strength, and microstructure as per the ASTM standards. The mechanical properties of the composite were evaluated and compared to the conventional. The microstructure of the composites was studied using optical microscopy to investigate the proper distribution of reinforcement and microstructure in the AHMNCs. The result indicates a significant improvement in the hardness. Further, the microstructure studies reveal that the reinforcement was fairly uniformly distributed over the matrix material.
The solid-liquid phase change processes are very sensitive to thermal boundary conditions. The ph... more The solid-liquid phase change processes are very sensitive to thermal boundary conditions. The phase change processes are also dominated by the shape of the cavity and thermo-physical properties of phase change materials. The transient experimental studies of unconstrained phase change processes are very difficult. Therefore, the numerical simulation is chosen to study the solidification phase change process in a rectangular and a spherical cavity. In this work, the solidification process of paraffin wax is simulated in a spherical cavity and a rectangular cavity for different thermal boundary conditions. The different sizes of cavities are taken to show the impact of shape on the solidification process. The simulations results are obtained using enthalpy-porosity model for free surface solidification process. The commercial software Ansys-fluent 16.2 is used to solve the numerical model. The model used for simulation is validated in previous work for melting in a spherical cavity [1] The result shows the solidification time is minimum for highest Stefan number. It also reveals that the solidification process is slow as the thickness of the solid zone increases. This is because of decreasing effect of natural convection and increasing effect of conductive resistance of solidified phase change material. The conduction dominated process makes the solidification slower as the thermal conductivity of paraffin wax is low. Different shapes of cavity, effects the solidification time. This research shows that though the size of spherical cavity is higher than that of rectangular cavity, the solidification time is much lower for spherical cavity.
Journal of The Institution of Engineers (India): Series C, 2012
The present research paper encompasses the systematic evaluation of a new type of aluminium alloy... more The present research paper encompasses the systematic evaluation of a new type of aluminium alloy metal matrix composite foam (Al-MMC) and its application as sound absorbing material for an assortment of industrial applications. The material was developed through melt foaming route using dual foaming agents i.e. TiH 2 and CaCO 3. Compressive behavioural analysis of the material, its elastic modulus and yield strength was determined which shows the material to have high-energy absorption capacity. The absorption behaviour of the material by impedance tube method reveals its good sound absorption properties, which is at par with other sound absorbing materials. Excellent sound absorption property coupled with good mechanical properties makes this material ideal for sound absorption under difficult situations.
Because of the increasing awareness of the environment and energy issues, as well as advances in ... more Because of the increasing awareness of the environment and energy issues, as well as advances in technology, the areas of application for annual plant fiber functional materials are expanding. In this work, two chemical treatments, alkalization (2 h agitation with 5% NaOH) and furfurylation (graft furfuryl alcohol followed by oxidation with (1N) NaClO 2 solution), were conducted on Luffa cylindrica fiber surfaces. The grafting of furfuryl alcohol followed by oxidation-generated quinines showed better results than alkaline treatment with respect to enhancement of surface area and hydrophobicity as well as wax, lignin, and hemicellulose extraction. The efficiency of chemical treatments was verified by elemental analysis and FTIR spectroscopy. Differential scanning calorimetry, thermo-gravimetric analysis, scanning electron microscopy, water absorption, and mechanical tests were performed to determine the thermal, mechanical, and morphological properties of untreated and chemically treated luffa fiber reinforced epoxy composites. Microstructures of the composites were examined to determine the mechanisms for the fiber-matrix interaction, which affects the thermal stability, water absorption, and mechanical behavior of the composites. The data from the water absorption process of composites at various temperatures were analyzed using a diffusion model based on Fick's law.
There is a long demand for light-weight, high-strength, and wear-resistance aluminium alloys, par... more There is a long demand for light-weight, high-strength, and wear-resistance aluminium alloys, particularly in automotive and aerospace industries. This demand is somewhat fulfilled by aluminium metal matrix composites. However, aluminium nano-metal matrix composite because of its superior properties is increasingly popular to replace aluminium metal matrix composites. The SiC (grit size is <90 nm) with purity 99.9% nanoparticle can enhance the properties of the base material in terms of tensile strength, hardness, microhardness, and mechanical strength. Pure Al (99.9%) matrix composites reinforced with SiC (purity 99.9%) nanoparticles are fabricated by liquid-state method with 1 wt% Mg, and their microstructure, mechanical properties (wear resistance, tensile behaviour, hardness), XRD, SEM were investigated. Here pure SiC purity 99.9% added into molten Al with 1 wt% Mg using squeeze die casting with furnace temperature 850 °C and pathway temperature 700 °C and for uniform mixing of SiC nanoparticles into matrix use stir method with 400 rpm for 2 min and pressure was 31.3 mpa. Pure Al and 1 wt% SiC nanocomposites with 1 wt% Mg were developed; the Al-SiC nanocomposites were characterised using scanning electron microscope (SEM) and X-ray diffraction (XRD). Due to used higher pressure during solidification, there is very low porosity. Stir is used before mixing the nano-SiC particle and pouring the metal into mould, which gives the uniform distribution of nanoparticles into matrix.
Advances in intelligent systems and computing, Nov 9, 2016
In continuous casting of steel, liquid steel is continuously solidified into a finished product. ... more In continuous casting of steel, liquid steel is continuously solidified into a finished product. Bokaro Steel Limited have slab caster and during continuous casting, one of the major operational irregularities encountered is breakout. A breakout is a hazard whereby the thin shell of the strand breaks, allowing the still-molten metal inside the strand to leak out from the mould, thus necessitating an expensive machine shutdown. Hence the breakout has a profound influence on the caster availability; affecting the productivity, cost of production, damage of machinery, safety hazards, etc. Breakouts occur due to the presence of a primary crack before solidification of liquid steel. Controlling the primary cracks lead to reduce chances of breakouts. Breakout prediction system of Bokaro Steel Limited uses only thermocouples temperature as an input of logic based algorithm controlled by strand PLC to predict breakout and generate alarm. This system sometimes generates lots of false alarm and sometimes even fails to generate an alarm before breakout. In this paper, two back-propagation neural networks are developed to predict the presence of primary crack that might lead to breakout of liquid steel. One is neural network1 train only with one input parameter (temperatures of thermocouples attached to the mould) and the other is neural network2 train with three input parameters (temperatures of thermocouples, casting speed and mould level). Both the neural network1 and network2 have only one output. Output of neural networks is either 0 for no alarm (no primary crack) or 1 for alarm (presence of primary crack) in breakout conditions. Comparison of the network1 with network2 showed that network2 has less output error, better performance and identifies primary crack more accurately. Performance of neural networks are done using Levenberg–Marquardt training algorithm, and also log sigmoid transfer function is used for both the hidden and output layer. The neural networks model training, validation and testing is done by simulating in Mat-Lab/Simulink.
Mold breakout is one of the significant problems in a continuous casting machine (caster). It rep... more Mold breakout is one of the significant problems in a continuous casting machine (caster). It represents one of the key areas within the steel production facilities of a steel plant. A breakout event on a caster will always cause safety hazards, high repair costs, loss of production, and shutdown of the caster for a short while. In this paper, a logic-judgment-based mold breakout prediction system has been developed for a continuous casting machine. This system developed new algorithms to detect the different sticker behaviors. With more algorithms running, each algorithm is more specialized in the other behaviors of stickers. This new logic-based breakout prediction system (BOPS) not only detects sticker breakouts but also detects breakouts that takes place due to variations in casting speed, mold level fluctuation, and taper/mold problems. This system also finds the exact location of the breakout in the mold and reduces the number of false alarms. The task of the system is to reco...
Metal foams are known to exhibit multifunctional behavior. It can offer a unique combination of s... more Metal foams are known to exhibit multifunctional behavior. It can offer a unique combination of several properties that cannot be achieved by one conventional material at the same time e.g. ultra-low density, high stiffness and capability to absorb crash energy, and excellent sound absorption properties. These unique combinations of properties indicate its various potential applications such as ultra light structures, in impact/blast absorption systems, and for sound absorption etc. Metal foam is a generic term for a class of material, which can be classified in terms of their structures, processing routes, and base metal. The main aim of this research work is to produce low cost, low-density aluminum foams by indigenously designed and fabricated equipment. This aluminum foam material possess all the positive attributes realized in current metal foam technology, such as high specific stiffness, low relative density, and high-energy absorption capacity. This material is designed to r...
Aluminium foams, which may replace all the energy absorbing materials in near future, are produce... more Aluminium foams, which may replace all the energy absorbing materials in near future, are produced by melting Aluminium alloy (LM6) containing blowing agent(s) and with continuous stirring of the melt. TiH2 is a known blowing agent for this. As TiH2 begins to decompose into Ti and gaseous H2 when heated above about 738K (465°C), large volumes of hydrogen gas are rapidly produced, creating bubbles that leads to manufacture of closed cell foam. Cellular materials like this produced foams has to be machined into pieces with desired shape for further investigation. In order to define the Compressive and impact properties of this material, LS-DYNA modeling and crashing simulation, which uniquely defines the mechanical behavior of this modified Al-MMC foam has been discussed in details.
Advances in Civil and Industrial Engineering, 2020
Additive manufacturing (AM) has developed and gained popularity across the globe into a multi-bil... more Additive manufacturing (AM) has developed and gained popularity across the globe into a multi-billion-dollar industry that involves many materials and techniques. AM has created itself as a technology for the manufacturing of metallic parts with enhanced mechanical characteristics that are scientifically sound and commercially feasible. However, there are various challenges, from business point of view, like high machine and material costs. Considering the complexities involved, sustainable manufacturing, optimization tools, and simulation models are necessary in order to save time and costly trial and errors. Topology optimization and simulation of AM processes are commercially available and are receiving attention from scientists and industry. Thus, this chapter is designed to provide readers with a brief introduction to AM technologies with typical applications. The main objective of this chapter is to provide the current trends and innovations in the field of design for additive...
Sustainable Engineering Products and Manufacturing Technologies, 2019
Abstract Semisolid metal processing (SSMP) is a novel metal forming technology which offers near ... more Abstract Semisolid metal processing (SSMP) is a novel metal forming technology which offers near net-shaped metal components of complex geometries. The present work aims to classify the currently available SSMP technologies and presents a comprehensive review of the potential mechanisms that lead to microstructural alterations during the production of feedstock material. Keeping in mind the current needs of the automobile and allied industries, the review of state-of-art research work was focused on thixoforming with an emphasis on aluminum-based alloys and composites. Focus was drawn on the two major SSMP routes: “rheo-casting” and “thixoforming.” The potential benefits and industrial applications were highlighted. Nondendritic microstructural evolution in the semisolid range and its beneficial effects is also emphasized. Considering the complexities involved in the areas of thixoforming for sustainable manufacturing, optimized solutions, are necessary. This chapter presents an overview of recent trends, and new challenges, for achieving sustainability at the product by taking Aluminum-based composites as the materials and thixoforming as the process focusing on the technology and system levels for achieving sustainability. Further, the mechanical properties of the thixoformed Al-based alloys and composites were presented and compared with gravity cast and rheo-cast conditions. Thus a critical assessment aimed at understanding the processing and structure–property relationships in the thixoformed alloys and composites in meeting the needs of the industry.
Aluminium hybrid metal matrix nano composite (AHMNC) material has all the advantages of conventio... more Aluminium hybrid metal matrix nano composite (AHMNC) material has all the advantages of conventional metal matrix nano composite with multifunctional properties because of the hybrid reinforcement. As a result, these materials offer a unique combination of properties that are not possible to achieve in conventional materials. The present study deals with the fabrication of aluminium hybrid nano composites by reinforcing Al2014 with nano sized B 4 C and graphite, processed through stir casting route followed by ultrasonic and squeeze casting. The addition of B 4 C improves the hardness, whereas Gr particles improve wear resistance in the composite. These combinations of the reinforcements are chosen for application under high abrasive conditions. Ultrasonic agitation has been done to uniformly distribute the reinforcement, whereas squeeze casting is done to reduce the porosity of the cast. The cast composite has been cut to prepare specimens for hardness, tensile strength, and microstructure as per the ASTM standards. The mechanical properties of the composite were evaluated and compared to the conventional. The microstructure of the composites was studied using optical microscopy to investigate the proper distribution of reinforcement and microstructure in the AHMNCs. The result indicates a significant improvement in the hardness. Further, the microstructure studies reveal that the reinforcement was fairly uniformly distributed over the matrix material.
Aluminium hybrid metal matrix nano composite (AHMNC) material has all the advantages of conventio... more Aluminium hybrid metal matrix nano composite (AHMNC) material has all the advantages of conventional metal matrix nano composite with multifunctional properties because of the hybrid reinforcement. As a result, these materials offer a unique combination of properties that are not possible to achieve in conventional materials. The present study deals with the fabrication of aluminium hybrid nano composites by reinforcing Al2014 with nano sized B 4 C and graphite, processed through stir casting route followed by ultrasonic and squeeze casting. The addition of B 4 C improves the hardness, whereas Gr particles improve wear resistance in the composite. These combinations of the reinforcements are chosen for application under high abrasive conditions. Ultrasonic agitation has been done to uniformly distribute the reinforcement, whereas squeeze casting is done to reduce the porosity of the cast. The cast composite has been cut to prepare specimens for hardness, tensile strength, and microstructure as per the ASTM standards. The mechanical properties of the composite were evaluated and compared to the conventional. The microstructure of the composites was studied using optical microscopy to investigate the proper distribution of reinforcement and microstructure in the AHMNCs. The result indicates a significant improvement in the hardness. Further, the microstructure studies reveal that the reinforcement was fairly uniformly distributed over the matrix material.
The solid-liquid phase change processes are very sensitive to thermal boundary conditions. The ph... more The solid-liquid phase change processes are very sensitive to thermal boundary conditions. The phase change processes are also dominated by the shape of the cavity and thermo-physical properties of phase change materials. The transient experimental studies of unconstrained phase change processes are very difficult. Therefore, the numerical simulation is chosen to study the solidification phase change process in a rectangular and a spherical cavity. In this work, the solidification process of paraffin wax is simulated in a spherical cavity and a rectangular cavity for different thermal boundary conditions. The different sizes of cavities are taken to show the impact of shape on the solidification process. The simulations results are obtained using enthalpy-porosity model for free surface solidification process. The commercial software Ansys-fluent 16.2 is used to solve the numerical model. The model used for simulation is validated in previous work for melting in a spherical cavity [1] The result shows the solidification time is minimum for highest Stefan number. It also reveals that the solidification process is slow as the thickness of the solid zone increases. This is because of decreasing effect of natural convection and increasing effect of conductive resistance of solidified phase change material. The conduction dominated process makes the solidification slower as the thermal conductivity of paraffin wax is low. Different shapes of cavity, effects the solidification time. This research shows that though the size of spherical cavity is higher than that of rectangular cavity, the solidification time is much lower for spherical cavity.
Journal of The Institution of Engineers (India): Series C, 2012
The present research paper encompasses the systematic evaluation of a new type of aluminium alloy... more The present research paper encompasses the systematic evaluation of a new type of aluminium alloy metal matrix composite foam (Al-MMC) and its application as sound absorbing material for an assortment of industrial applications. The material was developed through melt foaming route using dual foaming agents i.e. TiH 2 and CaCO 3. Compressive behavioural analysis of the material, its elastic modulus and yield strength was determined which shows the material to have high-energy absorption capacity. The absorption behaviour of the material by impedance tube method reveals its good sound absorption properties, which is at par with other sound absorbing materials. Excellent sound absorption property coupled with good mechanical properties makes this material ideal for sound absorption under difficult situations.
Additive manufacturing (AM) has developed and gained popularity across the globe into a multi-bil... more Additive manufacturing (AM) has developed and gained popularity across the globe into a multi-billion-dollar industry that involves many materials and techniques. AM has created itself as a technology for the manufacturing of metallic parts with enhanced mechanical characteristics that are scientifically sound and commercially feasible. However, there are various challenges, from business point of view, like high machine and material costs. Considering the complexities involved, sustainable manufacturing, optimization tools, and simulation models are necessary in order to save time and costly trial and errors. Topology optimization and simulation of AM processes are commercially available and are receiving attention from scientists and industry. Thus, this chapter is designed to provide readers with a brief introduction to AM technologies with typical applications. The main objective of this chapter is to provide the current trends and innovations in the field of design for additive manufacturing (DFAM), topology optimization, and simulation technologies.
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