scholarly journals IMAGE SYNTHESIS OF METAL FOAM MICRO-STRUCTURE WITH THE USE OF WANG TILES

2018 ◽  
Vol 15 ◽  
pp. 142-147
Author(s):  
Lukáš Zrůbek ◽  
Martin Doškář ◽  
Anna Kučerová ◽  
Marcela Meneses-Guzmán ◽  
Francisco Rodríguez-Méndez ◽  
...  
Keyword(s):  
Recent Work ◽  
Metal Foam ◽  
Design Method ◽  
Image Synthesis ◽  
Cellular Materials ◽  
Planar Domain ◽  
Micro Structure ◽  
Wang Tiles ◽  
Additional Step ◽  
Respective Number

<p>In this paper we present our recent work focused on the analysis of the abilities of Wang Tiles method and Automatic tile design method to synthesize the micro-structure of cellular materials, especially particular type of metal foam.</p><p>Wang Tiles method stores and compress the micro-structure in a set of Wang Tiles and by the means of stochastic tiling algorithms the planar domain is reconstructed. The used tiles are created by the Automatic tile design method from respective number of small specimens extracted from the original micro-structure image. As an additional step the central areas of automatically designed tiles are patched to suppress the influence of repeating tile edges (and relevant tile quarters) on inducing artifacts. In the presented analysis the performance of raw and patched tiles of different sizes in conjunction of various tile sets is investigated.</p>

Robust Design of Cellular Materials With Topological and Dimensional Imperfections

2006 ◽  
Vol 128 (6) ◽  
pp. 1285-1297 ◽  
Author(s):  
Carolyn Conner Seepersad ◽  
Janet K. Allen ◽  
David L. McDowell ◽  
Farrokh Mistree
Keyword(s):  
Large Scale ◽  
Design Method ◽  
Spatial Arrangement ◽  
Cellular Materials ◽  
Topology Design ◽  
Material Structure ◽  
Length Scales ◽  
Performance Requirements ◽  
Key Aspects ◽  
The Impact

A paradigm shift is underway in which the classical materials selection approach in engineering design is being replaced by the design of material structure and processing paths on a hierarchy of length scales for multifunctional performance requirements. In this paper, the focus is on designing mesoscopic material topology—the spatial arrangement of solid phases and voids on length scales larger than microstructures but smaller than the characteristic dimensions of an overall product. A robust topology design method is presented for designing materials on mesoscopic scales by topologically and parametrically tailoring them to achieve properties that are superior to those of standard or heuristic designs, customized for large-scale applications, and less sensitive to imperfections in the material. Imperfections are observed regularly in cellular material mesostructure and other classes of materials because of the stochastic influence of feasible processing paths. The robust topology design method allows us to consider these imperfections explicitly in a materials design process. As part of the method, guidelines are established for modeling dimensional and topological imperfections, such as tolerances and cracked cell walls, as deviations from intended material structure. Also, as part of the method, robust topology design problems are formulated as compromise Decision Support Problems, and local Taylor-series approximations and strategic experimentation techniques are established for evaluating the impact of dimensional and topological imperfections, respectively, on material properties. Key aspects of the approach are demonstrated by designing ordered, prismatic cellular materials with customized elastic properties that are robust to dimensional tolerances and topological imperfections.

3101 A design method for micro-structure of poroelastic sound-absorbing media by the homogenization method

2010 ◽  
Vol 2010.20 (0) ◽  
pp. _3101-1_-_3101-6_
Author(s):  
Takashi YAMAMOTO ◽  
Shinichi MARUYAMA ◽  
Kenjiro TERADA ◽  
Kazuhiro IZUI ◽  
Shinji NISHIWAKI
Keyword(s):  
Design Method ◽  
Homogenization Method ◽  
Micro Structure ◽  
Absorbing Media

Mechanical Properties of Closed Cellular Materials Containing Polymer

2009 ◽  
Author(s):  
Satoshi Kishimoto ◽  
Kimiyoshi Naito ◽  
Toru Shimizu ◽  
Fuxing Yin
Keyword(s):  
Internal Friction ◽  
Metal Foam ◽  
Pure Aluminum ◽  
High Energy ◽  
Cellular Materials ◽  
Acoustic Damping ◽  
High Energy Absorption ◽  
Damping Materials ◽  
Energy Absorbing ◽  
Compressive Tests

Cellular materials have unique thermal, acoustic, damping and energy absorbing properties that can be combined with their structural efficiency. Therefore, many kinds of cellular materials have been developed and tested as energy absorbing and damping materials. Particularly, closed cellular materials are thought to have many favorable properties and applications. In this study, a metallic closed cellular materials containing polymer was fabricated by the penetrating polymer into metal foam. The aluminum and stainless steel foams were selected for the metal foam and epoxy resin and polyurethane resin were selected for the penetrated polymer. The mechanical and damping properties of this material were measured. The results of the compressive tests show that this material has different stress-strain curves among the specimens that include different materials in the cells. Also, These results show that this material has high-energy absorption. The internal friction of this material was measured and the result shows that the internal friction of this material is larger than that of pure aluminum closed cellular material without any polymer and change with increasing of temperature.

Robust Topological Design of Cellular Materials

2003 ◽  
Author(s):  
Carolyn Conner Seepersad ◽  
Janet K. Allen ◽  
David L. McDowell ◽  
Farrokh Mistree
Keyword(s):  
Robust Design ◽  
Design Method ◽  
Cellular Materials ◽  
Design Methods ◽  
Topology Design ◽  
Research Areas ◽  
Topological Design ◽  
Capability Indices ◽  
Active Research ◽  
Design Techniques

A robust topology exploration method is under development in which robust design techniques are extended to the early stages of a design process when a product’s layout or topology is determined. The performance of many designs is strongly influenced by both topology, or the geometric arrangement and connectivity of a design, and potential variations in factors such as the operating environment, the manufacturing process, and specifications of the design itself. While topology design and robust design are active research areas, little attention has been devoted to integrating the two categories of design methods. In this paper, we move toward a comprehensive robust topology exploration method by coupling robust design methods, namely, design capability indices with topology design techniques. The resulting design method facilitates efficient, effective realization of robust designs with complex topologies. The method is employed to design extruded cellular materials with robust, desirable elastic properties. For this class of materials, 2D cellular topologies are customizable and largely govern multifunctional performance. By employing robust, topological design methods, we obtain cellular material designs that are characterized by ranged sets of design specifications with topologies that reliably meet a set of design requirements and are relatively simple and robust to anticipated variability.

Mechanical Properties of Metallic Closed Cellular Materials Containing Polymer Fabricated by Polymer Penetration

2010 ◽  
Vol 654-656 ◽  
pp. 2628-2631 ◽  
Author(s):  
Satoshi Kishimoto ◽  
Toru Shimizu ◽  
Fu Xing Yin ◽  
Kimiyoshi Naito ◽  
Yoshihisa Tanaka
Keyword(s):  
Mechanical Properties ◽  
Stainless Steel ◽  
Compressive Strength ◽  
Internal Friction ◽  
Epoxy Resin ◽  
Metal Foam ◽  
Cellular Materials ◽  
Polyurethane Resin ◽  
The Many ◽  
Compressive Tests

Metallic closed cellular materials containing polymer were fabricated by the penetrating polymer into metal foam. The aluminum and stainless steel foams were selected for the metal foam and epoxy resin and polyurethane resin were selected for the penetrated polymer. The many kinds of mechanical properties of this material were measured. The results of the compressive tests show that these materials have different stress-strain curves among the specimens that containing different materials in the cells. Also, this metallic closed cellular materials containing polymer have higher compressive strength, higher Young’s modules, higher energy absorption and higher internal friction than that of metallic closed cellular material without any polymer.

Robust Design of Cellular Materials With Topological and Dimensional Imperfections

2005 ◽  
Author(s):  
Carolyn Conner Seepersad ◽  
Janet K. Allen ◽  
David L. McDowell ◽  
Farrokh Mistree
Keyword(s):  
Large Scale ◽  
Design Method ◽  
Spatial Arrangement ◽  
Cellular Materials ◽  
Topology Design ◽  
Material Structure ◽  
Structure Property ◽  
Length Scales ◽  
Key Aspects ◽  
The Impact

A paradigm shift is underway in which the classical materials selection approach in engineering design is being replaced by the design of material structure and processing paths on a hierarchy of length scales for multifunctional performance requirements. In this paper, the focus is on designing mesoscopic material topology—the spatial arrangement of solid phases and voids on length scales larger than microstructures but smaller than the characteristic dimensions of an overall product. A robust topology design method is presented for designing materials on mesoscopic scales by topologically and parametrically tailoring them to achieve properties that are superior to those of standard or heuristic designs, customized for large-scale applications, and less sensitive to imperfections in the material. Imperfections are observed regularly in cellular material mesostructure and other classes of materials because of the stochastic nature of process-structure-property relationships. The robust topology design method allows us to consider imperfections explicitly in a materials design process. As part of the method, guidelines are established for modeling dimensional and topological imperfections, such as tolerances and cracked cell walls, as deviations from intended material structure. Also, as part of the method, robust topology design problems are formulated as compromise Decision Support Problems, and local Taylor-series approximations and strategic experimentation techniques are established for evaluating the impact of dimensional and topological imperfections, respectively, on material properties. Key aspects of the approach are demonstrated by designing ordered, prismatic cellular materials with customized elastic properties that are robust to dimensional tolerances and topological imperfections.

Mechanical Properties of Metallic Cellular Materials With Polymer

2010 ◽  
Author(s):  
Satoshi Kishimoto ◽  
Kimiyoshi Naito ◽  
Toru Shimizu ◽  
Fuxing Yin
Keyword(s):  
Mechanical Properties ◽  
Internal Friction ◽  
Metal Foam ◽  
Pure Aluminum ◽  
High Energy ◽  
Cellular Materials ◽  
Cellular Material ◽  
Polyurethane Resin ◽  
High Energy Absorption ◽  
Compressive Tests

A metallic cellular materials containing polymer was fabricated by the penetrating polymer into metal foam. The aluminum and stainless steel foams were selected for the metal foam and epoxy resin and polyurethane resin were selected for the penetrated polymer. The mechanical, damping shock absorbing properties of this material were measured. The results of the compressive tests show that this material has different stress-strain curves among the specimens that include different materials in the cells. Also, these results show that this material has high-energy absorption. The internal friction of this material was measured and the result shows that the internal friction of this material is larger than that of pure aluminum closed cellular material without any polymer and change with increasing of temperature. The shock absorbability of this material is larger than that of polymer and smaller than that of metallic cellular material.

The Sound Absorption Properties Comparison of Metal Foams and Flexible Cellular Materials

2018 ◽  
Vol 933 ◽  
pp. 357-366 ◽  
Author(s):  
Li Si Liang ◽  
Xiao Lei Wu ◽  
Na Ni Ma ◽  
Jin Jing Du ◽  
Man Bo Liu
Keyword(s):  
Absorption Coefficient ◽  
Sound Absorption ◽  
Metal Foam ◽  
Metal Foams ◽  
Cellular Materials ◽  
Glass Wool ◽  
Sound Absorption Coefficient ◽  
Absorption Properties ◽  
Average Value ◽  
Peak Value

The third octave sound absorption coefficient testing is conducted to compare the sound absorption properties metal foam and flexible cellular materials, by using sound absorption tester with the method of trasfer function sound absorption tester with the method of trasfer function. The sound absorption mechanisms are discussed by changing the parameters of sound absorption structure, such as the thickness of matrix materials and the thickness of cavity. The results show that pearl wool and glass wool exhibited excellent sound absorption properties. The peak value of sound absorption coefficient for pearl wool reaches to 0.991, and for glass wool, 0.985. The average sound absorption coefficient for pearl wool is 0.729, and for glass wool, 0.679. Among of three metal foams, the foamed aluminum material exhibited optimum sound absorption properties, and is superior to flexible sound absorption materials. The peak value of sound absorption coefficient reaches to 0.993, and the average value reaches to 0.781. This can be attributed to the flow resistance, porosity, thickness, cavity and structure factor, which influence the sound absorption of open cell materials.

What sentimentalists should say about emotion

2019 ◽  
Vol 42 ◽  
Author(s):  
Charlie Kurth
Keyword(s):  
Moral Judgment ◽  
Recent Work ◽  
Relevant Information ◽  
Moral Cognition ◽  
Multilevel Structure

Abstract Recent work by emotion researchers indicates that emotions have a multilevel structure. Sophisticated sentimentalists should take note of this work – for it better enables them to defend a substantive role for emotion in moral cognition. Contra May's rationalist criticisms, emotions are not only able to carry morally relevant information, but can also substantially influence moral judgment and reasoning.

The Sun as a Magnetic Star

1976 ◽  
Vol 32 ◽  
pp. 457-463
Author(s):  
John M. Wilcox ◽  
Leif Svalgaard
Keyword(s):  
Recent Work ◽  
Rotation Axis ◽  
Polar Field ◽  
Magnetic Star ◽  
Rotational Axis ◽  
Field Variation ◽  
The Sun ◽  
Arbitrary Angle ◽  
Solar Magnetism ◽  
Oblique Rotator

SummaryThe sun as a magnetic star is described on the basis of recent work on solar magnetism. Observations at an arbitrary angle to the rotation axis would show a 22-year polar field variation and a 25-day equatorial sector variation. The sector variation would be similar to an oblique rotator with an angle of 90° between the magnetic and rotational axis.

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