Comptes Rendus Mecanique最新文献_第3页

Physico-chemical approach of polymer chemical ageing: a short review 高分子化学老化的物理化学方法综述

IF 0.8 4区工程技术

Comptes Rendus Mecanique Pub Date : 2020-12-09 DOI: 10.5802/crmeca.64

E. Richaud

引用次数: 0

Identification methodology of a rate-sensitive constitutive law with mean field and full field modeling approaches for polycrystalline materials 基于平均场和全场建模方法的多晶材料速率敏感本构识别方法

IF 0.8 4区工程技术

Comptes Rendus Mecanique Pub Date : 2020-12-09 DOI: 10.5802/crmeca.56

Y. Charles, Chun-Lei Zhang, M. Gaspérini, B. Bacroix

{"title":"Identification methodology of a rate-sensitive constitutive law with mean field and full field modeling approaches for polycrystalline materials","authors":"Y. Charles, Chun-Lei Zhang, M. Gaspérini, B. Bacroix","doi":"10.5802/crmeca.56","DOIUrl":"https://doi.org/10.5802/crmeca.56","url":null,"abstract":"The present paper deals with the consideration of the rate-sensitivity mechanical behavior of metallic materials, in the framework of mean field and full field homogenization approaches. We re-examine the possibility of describing properly this rate sensitivity with a simple and widely used power law expressed at the level of the slip system, and we propose a methodology to accelerate the identification of the global material constitutive law for Finite Element (FE) simulations. For such an aim, simulations of a tensile test are conducted, using a simple homogenization model (the Taylor one, used in a relaxed constraint form) and an FE code (Abaqus), both using the same single-crystal rate-dependent constitutive law. It is shown that, provided that the identification of this law is performed with care and well adapted to the examined case (rate-sensitive or insensitive materials, static and/or dynamic ranges), the simple power law can be used to simulate the macroscopic behavior of polycrystalline aggregates in a wide range of strain rate (including both static and dynamic regimes) and strain-rate sensitivity values (up the rate-insensitive limit).","PeriodicalId":50997,"journal":{"name":"Comptes Rendus Mecanique","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2020-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72837147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Polycrystal thermo-elasticity revisited: theory and applications 再论多晶热弹性:理论与应用

IF 0.8 4区工程技术

Comptes Rendus Mecanique Pub Date : 2020-11-18 DOI: 10.5802/crmeca.18

C. Tomé, R. Lebensohn

{"title":"Polycrystal thermo-elasticity revisited: theory and applications","authors":"C. Tomé, R. Lebensohn","doi":"10.5802/crmeca.18","DOIUrl":"https://doi.org/10.5802/crmeca.18","url":null,"abstract":"The self-consistent (SC) theory is the most commonly used mean-field homogenization method to estimate the mechanical response behavior of polycrystals based on the knowledge of the properties and orientation distribution of constituent single-crystal grains. The original elastic SC method can be extended to thermo-elasticity by adding a stress-free strain to an elastic constitutive relation that expresses stress as a linear function of strain. With the addition of this independent term, the problem remains linear. Although the thermo-elastic self-consistent (TESC) model has important theoretical implications for the development of self-consistent homogenization of non-linear polycrystals, in this paper, we focus on TESC applications to actual thermo-elastic problems involving non-cubic (i.e. thermally anisotropic) materials. To achieve this aim, we provide a thorough description of the TESC theory, which is followed by illustrative examples involving cooling of polycrystalline non-cubic metals. The TESC model allows studying the effect of crystallographic texture and single-crystal elastic and thermal anisotropy on the effective thermo-elastic response of the aggregate and on the internal stresses that develop at the local level.","PeriodicalId":50997,"journal":{"name":"Comptes Rendus Mecanique","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2020-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84718259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Efficient simulation of single and poly-crystal plasticity based on the pencil glide mechanism 基于铅笔滑动机制的单晶和多晶塑性高效仿真

IF 0.8 4区工程技术

Comptes Rendus Mecanique Pub Date : 2020-11-18 DOI: 10.5802/crmeca.44

L. T. Le, K. Ammar, S. Forest

{"title":"Efficient simulation of single and poly-crystal plasticity based on the pencil glide mechanism","authors":"L. T. Le, K. Ammar, S. Forest","doi":"10.5802/crmeca.44","DOIUrl":"https://doi.org/10.5802/crmeca.44","url":null,"abstract":"The present work demonstrates that the pencil glide mechanism is a physically reliable and a computationally efficient model to simulate the nonlinear behaviour of b.c.c. single and polycrystals. For that purpose, the pencil glide extension of Schmid’s criterion used by Gilormini [1] is incorporated in a single crystal model and in a homogenized polycrystal model accounting for large elastoviscoplastic deformations. The response of the pencil glide model in terms of stress-strain curves and lattice rotation is compared to the prediction based on the consideration of all ({110}〈111〉+ {112}〈111〉) slip systems. In the case of α-iron single crystals both approaches are shown to accurately reproduce recent experimental results [2, 3]. The comparison is extended to α-iron polycrystals behaviour under tension, compression, rolling and simple shear loading conditions. The evolution of crystallographic textures obtained either based on pencil glide or using the 24 slip systems is analyzed and compared to classical experimental results from the literature. Limitations of the approach, especially in the case of simple shear textures, are also pointed out. The pencil glide approach can be viewed as a reduced order model enhancing computational efficiency of crystal plasticity simulations involving many slip mechanisms.","PeriodicalId":50997,"journal":{"name":"Comptes Rendus Mecanique","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2020-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84129049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Morphogenetic processes: from leaves to embryos 形态发生过程:从叶片到胚胎

IF 0.8 4区工程技术

Comptes Rendus Mecanique Pub Date : 2020-11-16 DOI: 10.5802/crmeca.33

L. Pauchard

引用次数: 0

Morphogenesis through elastic phase separation in a pneumatic surface 气动表面通过弹性相分离形成形态

IF 0.8 4区工程技术

Comptes Rendus Mecanique Pub Date : 2020-11-16 DOI: 10.5802/crmeca.43

Emmanuel Si'efert, B. Roman

引用次数: 2

Yves Couder: Putting mechanics back into the shoot apical meristem 伊夫·库德:将机制重新引入茎尖分生组织

IF 0.8 4区工程技术

Comptes Rendus Mecanique Pub Date : 2020-11-16 DOI: 10.5802/crmeca.19

J. Traas, O. Hamant

引用次数: 1

Exploring the relation between apical growth, organ formation and cell wall mechanics across land plant species 探讨陆地植物的顶端生长、器官形成和细胞壁力学之间的关系

IF 0.8 4区工程技术

Comptes Rendus Mecanique Pub Date : 2020-11-16 DOI: 10.5802/crmeca.28

A. Peaucelle

引用次数: 0

Shape dynamics of rotating polygons on the surface of liquid nitrogen in a Leidenfrost state Leidenfrost状态下液氮表面旋转多边形的形状动力学

IF 0.8 4区工程技术

Comptes Rendus Mecanique Pub Date : 2020-11-16 DOI: 10.5802/crmeca.24

Jacob Bach, A. Duchesne, T. Bohr

{"title":"Shape dynamics of rotating polygons on the surface of liquid nitrogen in a Leidenfrost state","authors":"Jacob Bach, A. Duchesne, T. Bohr","doi":"10.5802/crmeca.24","DOIUrl":"https://doi.org/10.5802/crmeca.24","url":null,"abstract":"When liquid nitrogen is set into rotation in a warm pot, the surface, initially forming an axissymmetrical, toroidal shape, spontaneously re-structures into a series of rotating polygons with a diminishing number of corners, while slowing down. This spontaneous “ordering” occurs despite the violently turbulent and boiling state of the fluid. We show experimentally that these shapes are well-described as a sum of a few Fourier modes, and we present experimental results for the development of the frequencies and amplitudes of these wave-modes during the transient process. We compare our results with the theoretical results for the instabilities of a potential vortex flow and argue that the first polygon formed in the transient process should be described by this theory. The paper is dedicated to the memory of Yves Couder, colleague, friend and a life-long source of inspiration. Résumé. Dans cet article nous nous intéressons au cas d’un volume d’azote liquide en état de caléfaction mis en rotation dans un récipient cylindrique chauffé. La surface libre du liquide, initialement sous forme d’un tore axisymétrique, va se déstabiliser et se restructurer en une série de polygones tournants dont le nombre de côtés diminue à mesure que le liquide ralentit. Ce facettage apparaît spontanément alors même que le liquide connait une violente ébullition et un écoulement extrêmement turbulent. Nous démontrons expérimentalement que les formes observées peuvent être décrites par la combinaison d’un petit nombre de modes de Fourier et nous étudions l’évolution de ces modes en termes d’amplitude et de fréquence depuis le premier polygone visible jusqu’à la fin de la rotation du liquide. Nous comparons nos résultats expérimentaux avec un modèle théorique décrivant la perte de stabilité des écoulements de type vortex potentiel et nous soutenons que le premier polygone observable suite à la déstabilisation de la forme axisymétrique peut être décrit par ce modèle. Cet article est dédié à la mémoire d’Yves Couder qui fut pour nous un collègue, un ami et une intarissable source d’inspiration.","PeriodicalId":50997,"journal":{"name":"Comptes Rendus Mecanique","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87480046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Walkers in a wave field with memory 波场中有记忆的行尸

IF 0.8 4区工程技术

Comptes Rendus Mecanique Pub Date : 2020-11-16 DOI: 10.5802/crmeca.29

O. Devauchelle, E. Lajeunesse, F. James, C. Josserand, P. Lagrée

引用次数: 3