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Micro-lattice structures with variable strut diameter
Brulík, Karel ; Jaroš, Jan (referee) ; Červinek, Ondřej (advisor)
Due to their specific properties, micro-lattice structures have a great potential for use in energy absorption applications. It turns out that conventional micro-lattice structures with constant volume fraction can be designed for a known amount of absorbed energy. In real applications, however, we often do not know it in advance. Therefore, the use of functionally graded micro-lattice structures, which can be designed for a wider range of applied energies, appears to be more promising. The aim of this work is to compare micro-lattice structures with variable strut diameter made from 316L stainless steel by Selective Laser Melting technology in terms of energy absorption capability. For this purpose, two types of structures, F2BCC and F2BCC_45, were fabricated, both in configuration with constant, continuously variable and stepwise variable strut diameter. The structures were subsequently dynamically loaded using a drop-weight test, the results of which were described by the time history of deformation and forces. The greater amount of absorbed energy was measured for structures of type F2BCC_45, up to 73 % depending on the configuration of the structures. The results revealed that the variable strut diameter does not have a large effect on the amount of absorbed energy, but it significantly reduces the shock generated, up to 54 % depending on the type and configuration of the structure. This thesis provides a comprehensive view of the deformation and stress characteristics of both types of structures, and in particular a comparison of the effect of variable strut diameter.
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Effect of layer thickness on critical angle of additively manufactured lattice structures
Nosek, Jakub ; Vrána, Radek (referee) ; Vaverka, Ondřej (advisor)
Aim of this work is to describe the effect of a layer thickness on critical angel of a lattice structures manufactured by SLM technology. The effect of layer thickness was investigated on single struts and on lattice structures made from stainless steel 316L. Better geometrical accuracy could be obtained, if the smaller layer thickness is used. Less attached powder particles on downskins was also observed on lattice structures. Thanks to this thesis, it is possible to determine, if it is meaningful to decrease the layer thickness in order to improve manufacturability of lattice structures even with higher manufacturing time.
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Comparison of micro-lattice structures for energy absorption
Koban, Tomáš ; Vrána, Radek (referee) ; Červinek, Ondřej (advisor)
Additively manufactured metal micro-structures have great potential in energy absorption applications. The recent research in this field led to a much better understanding of failure behaviour of these micro-structures. This thesis focuses on comparison of energy absorption ability of strut-based micro-lattice structures manufactured by selective laser melting depending on their topology and basic material. Energy absorption of three types of lattice structures (BCC, BCCZ, GBCC) made from stainless steel 316L and aluminium alloy AlSi10Mg was examined. Specific energy absorption was used to compare the two materials. The results show that micro-lattice structures made from stainless steel outperform the aluminium ones in energy absorption ability. The highest amount of absorbed energy was measured for BCCZ structure. This thesis describes the failure mechanism of micro-lattice structures and offers a complex evaluation of energy absorption for both materials.
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The study of the effect of additive manufacturing technology parameters Selective Laser Melting properties of the produced object
Žabka, Marek ; Koukal, Ondřej (referee) ; Vrána, Radek (advisor)
Metal additive technology currently finds use in a large number of industrial sectors. Mainly in domains such as aviation, medicine and astronautics, the emphasis is laid on mechanical and material properties of materials. This bachelor thesis deals with the research study of process parameters of technology Selective Laser Melting for material AlSi10Mg and stainless steel 316L. In thesis the impact analysis of main process parameters: laser power, scanning speed, hatch distance, layer thickness, especially on the porosity of the samples was carried out. Recommended settings for both materials were found based on the research of the current state. It was further found out the influence of parameters such as powder humidity or laser scan strategy.
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Micro-lattice structures with variable strut diameter
Brulík, Karel ; Jaroš, Jan (referee) ; Červinek, Ondřej (advisor)
Due to their specific properties, micro-lattice structures have a great potential for use in energy absorption applications. It turns out that conventional micro-lattice structures with constant volume fraction can be designed for a known amount of absorbed energy. In real applications, however, we often do not know it in advance. Therefore, the use of functionally graded micro-lattice structures, which can be designed for a wider range of applied energies, appears to be more promising. The aim of this work is to compare micro-lattice structures with variable strut diameter made from 316L stainless steel by Selective Laser Melting technology in terms of energy absorption capability. For this purpose, two types of structures, F2BCC and F2BCC_45, were fabricated, both in configuration with constant, continuously variable and stepwise variable strut diameter. The structures were subsequently dynamically loaded using a drop-weight test, the results of which were described by the time history of deformation and forces. The greater amount of absorbed energy was measured for structures of type F2BCC_45, up to 73 % depending on the configuration of the structures. The results revealed that the variable strut diameter does not have a large effect on the amount of absorbed energy, but it significantly reduces the shock generated, up to 54 % depending on the type and configuration of the structure. This thesis provides a comprehensive view of the deformation and stress characteristics of both types of structures, and in particular a comparison of the effect of variable strut diameter.
|
|
|
Comparison of micro-lattice structures for energy absorption
Koban, Tomáš ; Vrána, Radek (referee) ; Červinek, Ondřej (advisor)
Additively manufactured metal micro-structures have great potential in energy absorption applications. The recent research in this field led to a much better understanding of failure behaviour of these micro-structures. This thesis focuses on comparison of energy absorption ability of strut-based micro-lattice structures manufactured by selective laser melting depending on their topology and basic material. Energy absorption of three types of lattice structures (BCC, BCCZ, GBCC) made from stainless steel 316L and aluminium alloy AlSi10Mg was examined. Specific energy absorption was used to compare the two materials. The results show that micro-lattice structures made from stainless steel outperform the aluminium ones in energy absorption ability. The highest amount of absorbed energy was measured for BCCZ structure. This thesis describes the failure mechanism of micro-lattice structures and offers a complex evaluation of energy absorption for both materials.
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|
|
Effect of layer thickness on critical angle of additively manufactured lattice structures
Nosek, Jakub ; Vrána, Radek (referee) ; Vaverka, Ondřej (advisor)
Aim of this work is to describe the effect of a layer thickness on critical angel of a lattice structures manufactured by SLM technology. The effect of layer thickness was investigated on single struts and on lattice structures made from stainless steel 316L. Better geometrical accuracy could be obtained, if the smaller layer thickness is used. Less attached powder particles on downskins was also observed on lattice structures. Thanks to this thesis, it is possible to determine, if it is meaningful to decrease the layer thickness in order to improve manufacturability of lattice structures even with higher manufacturing time.
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The study of the effect of additive manufacturing technology parameters Selective Laser Melting properties of the produced object
Žabka, Marek ; Koukal, Ondřej (referee) ; Vrána, Radek (advisor)
Metal additive technology currently finds use in a large number of industrial sectors. Mainly in domains such as aviation, medicine and astronautics, the emphasis is laid on mechanical and material properties of materials. This bachelor thesis deals with the research study of process parameters of technology Selective Laser Melting for material AlSi10Mg and stainless steel 316L. In thesis the impact analysis of main process parameters: laser power, scanning speed, hatch distance, layer thickness, especially on the porosity of the samples was carried out. Recommended settings for both materials were found based on the research of the current state. It was further found out the influence of parameters such as powder humidity or laser scan strategy.
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