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EML Special Issue on Mechanics in Energy Materials

Now receiving new submissions for the special issue on mechanics in energy materials.

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Strengthening high-stacking-fault-energy metals via parallelogram nanotwins

A variety of questions remain open in the new form of nanotwins in Ni, welcome any comments! 

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Symposium on Mechanics in Energy Storage and Conversion at SES 2015 meeting

Dear Colleagues:

please consider to attend the symposium titled" Mechanics in Energy Storage and Conversion" as part of the society of engineering science 52nd annual technical meeting to be held at Texas A&M, Oct 26-28, 2015.

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Symposium on Mechanics of Materials in Energy Technologies at McMAT2015

Dear Colleagues,

Please consider to attend the symposium entitled  "Mechanics of Materials in Energy Technologies"  at the occasion of ASME 2015 Applied Mechanics and Materials Conference, 6.29-7.1, 2015, in Seattle.The conference occurs every four years and covers all aspects of mechanics and materials: theoretical, experimental, and computational.

The description of the symposium is below.

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Symposium on Li-ion batteries at the SES 50th annual meeting

Dear Colleagues,

Please consider to attend the symposium entitled  "Lithium ion batteries - when chemistry meets mechanics"  at the occasion of the Joint Society of Engineering Science (SES) 50th Annual Technical Meeting and ASME-AMD Annual Summer Meeting, July 28-31, 2013, at Brown University.

The description of the symposium is attached below.

The following speakers will contribute invited talks in the symposium: Yi Cui, William D. Nix, Martin Bazant, Brian Sheldon, Gleb Yushin, Scott Mao, Reiner Moenig, and Yue Qi

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Fracture and debonding in lithium-ion batteries with electrodes of hollow core-shell nanostructures

In a novel design of lithium-ion batteries, hollow electrode particles coated with stiff shells are used to mitigate mechanical and chemical degradation.  In particular, silicon anodes of such core-shell nanostructures have been cycled thousands of times with little capacity fading.  To reduce weight and to facilitate lithium diffusion, the shell should be thin.  However, to avert fracture and debonding from the core, the shell must be sufficiently thick.

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Lithium-assisted plastic deformation of silicon electrodes in lithium-ion batteries: a first-principles theoretical study

Silicon can host a large amount of lithium, making it a promising electrode for high-capacity lithium-ion batteries.  Recent experiments indicate that silicon experiences large plastic deformation upon Li absorption, which can significantly decrease the stresses induced by lithiation and thus mitigate fracture failure of electrodes. These issues become especially relevant in nanostructured electrodes with confined geometries.

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Inelastic hosts as electrodes for high-capacity lithium-ion batteries

Silicon can host a large amount of lithium, making it a promising electrode for high-capacity lithium-ion batteries.  Upon absorbing lithium, silicon swells several times its volume; the deformation often induces large stresses and pulverizes silicon.

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Fracture of electrodes in lithium-ion batteries caused by fast charging

During charging or discharging of a lithium-ion battery, lithium is extracted from one electrode and inserted into the other.  This extraction-insertion reaction causes the electrodes to deform.  An electrode is often composed of small active particles in a matrix.  If the battery is charged at a rate faster than lithium can homogenize in an active particle by diffusion, the inhomogeneous distribution of lithium results in stresses that may cause the particle to fracture.  The distributions of lithium and stress in a LiCoO2 particle

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ES247: Fracture Mechanics, Fundamentals and Applications. 3rd Edition

The book I recommend for reading is Fracture mechanics: fundamentals and applications, by T.L.Anderson, 3rd edition, 2005. I first saw this book on the top list of reading materials of Brown U. When I have it I found so pleasent to read through it. Here is the short-list of its content

Chapter 1: Introduction: History and overview

Chapter 2:Fundamental concepts: linear elastic fracture mechanics

Chapter 3: Elastic-plastic mechanics

Chapter 4: Dynamic and time-dependent fracture

Chapter 5: Material behavior: Fracture mechanics in metals

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ES241Presentation: General theory of finite deformation

Please see attachment for ES241 final presentation--general theory of finite deformation

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Kejie Zhao

Hi everyone, very glad to see you here. My name is Kejie Zhao, a first year phd student working in Prof.Zhigang Suo's group ( My concentration is solid mechanics with the same name of this course, it also signifies its importance to my future research. I graduate from Xi'an Jiaotong University in China before coming to Harvard. There I obtained my bachelor and master degree in Engineering Mechanics and Solid Mechanics respectively.

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Multiaxial behavior of nanoporous single crystal copper: a molecular dynamics study

The stress-strain behavior and incipient yield surface of nanoporous single crystal copper are studied by the molecular dynamics (MD) method. The problem is modeled by a periodic unit cell subject to multi-axial loading. The loading induced defect evolution is explored. The incipient yield surfaces are found to be tension-compression asymmetric. For given void volume fraction, apparent size effects in the yield surface are predicted: the smaller behaves stronger.

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Question: Is the local energy dictating dislocation emission constant for single crystal?

Hi everyone, in my size dependence study, I find the local energy dictating dislocation emission is almost constant for varied sized samples, in given directions of single crystal. I don't know this is an interesing finding, or just a common sense. Will you give me some suggestion, Thank you!



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