Compression of Heterogeneous Material Systems Based on Wang Tilings

The present study is on the concept of modeling of heterogeneous materials by means of Wang tilings. The central idea is to store a microstructural information within a finite set of Wang Tiles, which allow for reconstructing heterogeneity patterns of random media in planar domains of arbitrary sizes. The particular objective of presented work is our automatic tile set designer in conjunction with stochastic tiling synthesis algorithm. The proposed methodology is demonstrated on different examples. The proximity of synthesized microstructures to reference media is explored by statistical descriptors and discussed in terms of parasitic spatial orientation orders that may occur.

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Adaptive Boundaries of Wang Tiles for Heterogeneous Material Modelling

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1144.159 ◽

2017 ◽

Vol 1144 ◽

pp. 159-166

Author(s):

David Šedlbauer

Keyword(s):

Molecular Dynamics ◽

Heterogeneous Materials ◽

Heterogeneous Material ◽

Unit Cell ◽

Material Modelling ◽

Wang Tiles ◽

Materials Modelling ◽

Small Set ◽

Wang Tile ◽

Periodic Unit Cell

This contribution deals with algorithms for the generation of modified Wang tiles as a tool for the heterogeneous materials modelling. The proposed approach considers material domains only with 2D hard discs of both equal and different radii distributed within a matrix. Previous works showed potential of the Wang tile principles for reconstruction of heterogeneous materials. The main advantage of the tiling theory for material modelling is to stack large/infinite areas with relative small set of tiles with emphasis on a periodicity reduction in comparison with the traditional Periodic Unit Cell (PUC) concept. The basic units of the Wang Tiling are tiles with codes (colors) on edges. The algorithm for distribution of hard discs is based on the molecular dynamics to avoid particles overlapping. Unfortunately the nature of the Wang tiling together with molecular dynamics algorithms cause periodicity artefacts especially in tile corners of a composed material domain. In this paper a new algorithm with adaptive tile boundaries is presented in order to avoid edge and corner periodicity.

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STRUCTURE OF SHOCKWAVES IN LAYERED HETEROGENEOUS MATERIAL SYSTEMS: EXPERIMENTAL RESULTS

Structural Stability and Dynamics ◽

10.1142/9789812776228_0154 ◽

2002 ◽

Author(s):

L. Tsai ◽

V. Prakash

Keyword(s):

Heterogeneous Material ◽

Experimental Results ◽

Material Systems

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Mass partitioning effects in diffusion transport

Physical Chemistry Chemical Physics ◽

10.1039/c5cp02720a ◽

2015 ◽

Vol 17 (32) ◽

pp. 20630-20635 ◽

Cited By ~ 13

Author(s):

Milos Kojic ◽

Miljan Milosevic ◽

Suhong Wu ◽

Elvin Blanco ◽

Mauro Ferrari ◽

...

Keyword(s):

Heterogeneous Material ◽

Diffusive Transport ◽

Diffusion Transport ◽

Material Systems ◽

Substantial Control

Mass partitioning may have a substantial control over diffusive transport in heterogeneous material systems.

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SYNTHESIZING THE LÜ ATTRACTOR BY PARAMETER-SWITCHING

International Journal of Bifurcation and Chaos ◽

10.1142/s0218127411028441 ◽

2011 ◽

Vol 21 (01) ◽

pp. 323-331 ◽

Cited By ~ 3

Author(s):

MARIUS-F. DANCA

Keyword(s):

Finite Time ◽

Present Author ◽

Control Parameter ◽

Initial Value ◽

Step Size ◽

Time Intervals ◽

Synthesis Algorithm ◽

Finite Set ◽

Parameter Values ◽

Parameter Switching

In this letter we synthesize numerically the Lü attractor starting from the generalized Lorenz and Chen systems, by switching the control parameter inside a chosen finite set of values on every successive adjacent finite time intervals. A numerical method with fixed step size for ODEs is used to integrate the underlying initial value problem. As numerically and computationally proved in this work, the utilized attractors synthesis algorithm introduced by the present author before, allows to synthesize the Lü attractor starting from any finite set of parameter values.

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Microstructure Representation and Reconstruction of Heterogeneous Materials Via Deep Belief Network for Computational Material Design

Journal of Mechanical Design ◽

10.1115/1.4036649 ◽

2017 ◽

Vol 139 (7) ◽

Cited By ~ 47

Author(s):

Ruijin Cang ◽

Yaopengxiao Xu ◽

Shaohua Chen ◽

Yongming Liu ◽

Yang Jiao ◽

...

Keyword(s):

Wide Spectrum ◽

Heterogeneous Material ◽

Feature Space ◽

Material Design ◽

Deep Belief Network ◽

Synthesis Methods ◽

Reconstruction Process ◽

Complex Material ◽

Belief Network ◽

Material Systems

Integrated Computational Materials Engineering (ICME) aims to accelerate optimal design of complex material systems by integrating material science and design automation. For tractable ICME, it is required that (1) a structural feature space be identified to allow reconstruction of new designs, and (2) the reconstruction process be property-preserving. The majority of existing structural presentation schemes relies on the designer's understanding of specific material systems to identify geometric and statistical features, which could be biased and insufficient for reconstructing physically meaningful microstructures of complex material systems. In this paper, we develop a feature learning mechanism based on convolutional deep belief network (CDBN) to automate a two-way conversion between microstructures and their lower-dimensional feature representations, and to achieve a 1000-fold dimension reduction from the microstructure space. The proposed model is applied to a wide spectrum of heterogeneous material systems with distinct microstructural features including Ti–6Al–4V alloy, Pb63–Sn37 alloy, Fontainebleau sandstone, and spherical colloids, to produce material reconstructions that are close to the original samples with respect to two-point correlation functions and mean critical fracture strength. This capability is not achieved by existing synthesis methods that rely on the Markovian assumption of material microstructures.

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A Study on Strengthening Mechanical Properties of a Punch Mold for Cutting by Using an HWS Powder Material and a DED Semi-AM Method of Metal 3D Printing

Journal of Manufacturing and Materials Processing ◽

10.3390/jmmp4040098 ◽

2020 ◽

Vol 4 (4) ◽

pp. 98 ◽

Cited By ~ 2

Author(s):

Seong-Woong Choi ◽

Yong-Seok Kim ◽

Young-Jin Yum ◽

Soon-Yong Yang

Keyword(s):

Mechanical Properties ◽

Wear Resistance ◽

Powder Material ◽

Hot Stamping ◽

Heterogeneous Materials ◽

Heterogeneous Material ◽

High Strength ◽

High Wear Resistance ◽

Metal 3D Printing ◽

Directed Energy

The post-processing (punching or trimming) of high-strength parts reinforced by hot stamping requires punch molds with improved mechanical properties in hardness, resistance to wear, and toughness. In this study, a semi-additive manufacturing (semi-AM) method of heterogeneous materials was proposed to strengthen these properties using high wear resistance steel (HWS) powder and directed energy deposition (DED) technology. To verify these mechanical properties as a material for the punch mold for cutting, specimens were prepared and tested by a semi-AM method of heterogeneous material. The test results of the HWS additive material by the semi-AM method proposed in this study are as follows: the hardness was 60.59–62.0 HRc, which was like the Bulk D2 specimen. The wear resistance was about 4.2 times compared to that of the D2 specimen; the toughness was about 4.0 times that of the bulk D2 specimen; the compressive strength was about 1.45 times that of the bulk D2 specimen; the true density showed 100% with no porosity. Moreover, the absorption energy was 59.0 J in a multi-semi-AM specimen of heterogeneous materials having an intermediate buffer layer (P21 powder material). The semi-AM method of heterogeneous materials presented in this study could be applied as a method to strengthen the punch mold for cutting. In addition, the multi-semi-AM method of heterogeneous materials will be able to control the mechanical properties of the additive material.

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Gradient-Based Wang Tiles Texture Synthesis Algorithm with Adaptive Block Size

Laser & Optoelectronics Progress ◽

10.3788/lop54.051001 ◽

2017 ◽

Vol 54 (5) ◽

pp. 051001 ◽

Cited By ~ 1

Author(s):

谭永前 Tan Yongqian ◽

曾凡菊 Zeng Fanju

Keyword(s):

Texture Synthesis ◽

Block Size ◽

Synthesis Algorithm ◽

Wang Tiles ◽

Gradient Based

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Modeling the Behavior of Heterogeneous Materials with Non Linear Couplings using “Translated Fields”

MRS Proceedings ◽

10.1557/proc-881-cc1.9 ◽

2005 ◽

Vol 881 ◽

Cited By ~ 2

Author(s):

S. Berbenni ◽

V. Favier ◽

M. Berveiller

Keyword(s):

Strain Rate ◽

Effective Properties ◽

Consistency Condition ◽

Heterogeneous Materials ◽

Heterogeneous Material ◽

Projection Operators ◽

Unknown Boundary ◽

Inhomogeneous Materials ◽

Macro Scale ◽

Non Linear

AbstractThe determination of the behavior of heterogeneous materials with complex physical and mechanical couplings constitutes a challenge in the design of new materials and the modeling of their effective properties. In real inhomogeneous materials, the simultaneous presence of elastic mechanisms and non linear inelastic ones (viscoplastic, magnetic, ferroelectric, shape memory effect etc.) leads to a complex non linear coupling between the mechanical fields which is tricky to represent in a simple and efficient way. Hence, for many situations the effective global behavior does not follow the same structure than the local constitutive one. Regarding space-time couplings for instance, a heterogeneous material composed of phases described by Maxwell elements can not be considered as a Maxwellian solid at the macro scale.In this paper, we introduce a new micro-macro approach based on translated fields in its generalized form to be applied to different coupled phenomena. The local total strain (rate) is composed additively of an elastic strain (rate) and an inelastic one which is no more limited to be “stress free” as considered originally by Kröner. An extended (non conventional) self-consistent model is then proposed starting from the integral equation for a translated strain (rate) field and using the projection operators algebra introduced by Kunin. The chosen translated field is the compatible inelastic strain (rate) of the fictitious inelastic heterogeneous medium submitted to a uniform unknown boundary condition. The self-consistency condition amounts to define analytically these boundary conditions so that a relative simple and compact strain (rate) concentration equation is obtained.In order to illustrate the method, the case of a non linear elastic-viscoplastic coupling is developed and applied to different classes of composites and polycrystals.

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