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Electro-creasing instability in deformed polymers: experiment and theory

Submitted by Qiming Wang on Mon, 06/06/2011 - 19:03

research

electromechanical instability

dielectrics

electro-creasing instability

pattern formation

SAMs Lab research

Electro-creasing instability in deformed polymers: experiment and theory

Qiming Wang, Mukarram Tahir, Lin Zhang, and Xuanhe Zhao*

Soft Matter, In Press

The Results of The 1st Y.C. Fung Student Paper Competition on Biomechanics, Biophysics, and Biomatreriomics

Submitted by shaofanli on Mon, 06/06/2011 - 02:08

research

The final phase of The 1st Y.C. Fung Student Paper Competition on Biomechanics, Biophysics, and Biomatreriomics was held at Northeastern University, Boston, on June 3rd, 2011.

Seven finalists have participated the oral presentation, and they are:

Egor Dontsov from the University of Minnesota,

Combining UMAT with XFEM

Submitted by Panos Efthymiadis on Tue, 05/31/2011 - 10:12

Hi all,

I 'd like to ask whether anyone has applied XFEM for a user-material (UMAT). What is the process to do that? Could anyone provide some advice, documentation or guidelines?

All the best,

Panos

p.s. I 've heard that a UEL code is needed to couple XFEM with UMAT.

Universal Stability and Temperature Dependent Phase Transformation in Group VIIIB–IB Transition Metal FCC Nanowires.

Submitted by Vijay Kumar Sutrakar on Sun, 05/29/2011 - 12:21

research

I want to share our recent research work on FCC metallic nanowires, which is published in Journal of Physical Chemistry - C (ACS Publications). The abstract of the paper is given below. Further details can be found at " Sutrakar et al J. Phys. Chem. C, 2011, 115 (21), pp 10394–10398

DOI: 10.1021/jp2006815

HOW IS THE STRESS AND STRAIN DISTRIBUTION NEAR THE FATIGUE CRACK TIP ?

Submitted by Chen Long on Sat, 05/28/2011 - 01:40

research

Dear friend:

As known to all, the magnitude of the stress/strain at the crack tip is mathematically infinite,while it is physically finite. So,what i am concerned is how to caculate the value of the stress/strain at the tip.What's more, i doubt that whether the CTOD is constant during the propogation process.if yes.so can i take a constant range of the limited stress/strain near the crack tip? If there is any reply ,i will be appreciated!

Journal Club Theme of June 2011: Dynamic Mechanical Behavior of Advanced Structural Materials

Submitted by qwei on Fri, 05/27/2011 - 14:30

research

shock loading

high-strain rate loading

dynamic mechanical properties

ultrafine grained metals

nanocrystalline metals

Split Hopkinson Pressure bar (or Kolsky bar)

adiabatic shear band

The response of structural materials to external mechanical load may strongly depend on the rate at which the load is imposed. For example, a specimen may exhibit ductile fracture if loaded at quasi-static rate (strain rate below 1.0/s), but may show brittle fracture under impact (high-rate) loading. According to the classic monograph of Professor Marc Meyers, if the strain rate is above 100/s, it can be put into the high-strain rate regime. The mechanical behavior of structural materials under such loading conditions is dubbed dynamic.

Dynamic Auxiliary Fields for Interaction Integral

Submitted by Matin Parchei on Fri, 05/27/2011 - 12:49

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Fracture Mechanics Forum

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Dear friends,

I am writing an XFEM code for dynamic crack propagation and interested in using the Interaction Integral method (as in Rethore et al. (2005)) for computation of Stress Intensity Factors (SIFs). I wonder if anyone knows what kind of dynamic asymptotic crack tip auxiliary fields could be applied to the method for computation of SIFs for a dynamically propagating crack.

Regards

Matin

How to simulate compaction process of powder mettalurgy?

Submitted by gurumoorthy.s on Fri, 05/27/2011 - 10:24

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I am doing ph.d work related to powder mettalurgy

I want to simulate the compaction process ( in powder mettalurgy) by using ABAQUS.It is very essential to find a way to create a model which will behave as such as PM part.

After modeling it is next work to find the proper analysis method to do analysis by applying compressive load to study the deformation of the PM Part. In ABAQUS, Modified Drucker-Prager cap model is widely used for the compaction problems of different metals in many research papers.

I have 2 problems.

A homogenization analysis of the field theoretic approach to the quasi-continuum method

Submitted by Vikram Gavini on Thu, 05/26/2011 - 21:38

Dear Colleagues,

I wish to bring to your attention my recent work with Liping Liu on "A homogenization analysis of the field theoretic approach to the quasi-continuum method" to appear in the Journal of the Mechanics and Physics of Solids. Below is the abstract and attached is the preprint of the article. I will very much appreciate your comments and suggestions.

A Homogenization Analysis of the Field Theoretic Approach to the Quasi-Continuum Method