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Job opening for FEM developer - Principal Research Scientist

Scientific Forming Technologies Corporation (SFTC) is currently looking for several self-motivated and talented individuals to further develop its Finite Element based software product DEFORM™.  Please visit for more details.  Ph.D in Engineering with strong background in mechanics, and/or manufacturing processes, and programming experience (FORTRAN under Windows or UNIX environment), and excellent problem solving skills are highly desirable.

Tony Evans passed away

evans Tony Evans passed away on Wednesday after a long and valiant fight against cancer.  He was Alcoa Professor of Materials, Professor of Mechanical Engineering and Director of the Center for Multifunctional Materials and Structures at the University of California at Santa Barbara.

v.tagarielli's picture

PhD studentship @ University of Oxford

A fully funded PhD research studentship is available at the University of Oxford, in the Solid Mechanics Group.

A Different Kind of a Book Involving Electromagnetism and Potential Theory

Unlike other blog-posts of mine, I am not going "own" this particular thread. By that, I mean to say: I am going to only begin this thread and immediately turn it over to you completely. I am not going to watch over whether the discussion here continues to stick to its main theme or not, whether it slides into some minor side issues, whether it deserts the main theme altogether, etc., the way I usually do.

- - - - -

how can i measure local stress and strain in fatigue crack tip?

It seems that the measurment of local stress and strain in fatigue crack tip will be difficult. some researcher use F.E analysis method,in contrary using of numerical solution. however analytical method also has investigated. what method you can imagine? i need a brain storm in this issue.


Thank you


Haimin Yao's picture

Science Channel Tonight at 9:00pm

Dear Colleagues,

May I have your attention please? It's air time for the second episode of "Popular Science's Future of...Combat".  The show will air on The Science Channel ( at 9pm ET/PT on 9/07/09. The research on biological armors by Christine Ortiz's group from MIT will be reported.



lagrangian and eulerian coordinates

What is the difference between Eulerian and Lagrangian coordinates?

I have read that, Eulerian coordinates correspond to spatial points and Lagrangian correspond to material points.

A material point corresponds to a spatial coordinate in initial configuration?

I'm , however, not able to get the diference between the two.Can anyone explain?

In conventional linear finite element analysis, what do we use?Lagrangian or Eulerian mesh?

Nanshu Lu's picture

The effect of film thickness on the failure strain of polymersupported metal films

We perform uniaxial tensile tests on polyimide-supported copper films with a strong (111) fiber texture and with thicknesses varying from 50 nm to 1 μm. Films with thicknesses below 200 nm fail by intergranular fracture at elongations of only a few percent. Thicker films rupture by ductile transgranular fracture and local debonding from the substrate. The failure strain for transgranular fracture exhibits a maximum for film thicknesses around 500 nm.

Zhijun Zheng's picture

Two positions for guest researchers(post-doc) at NIST on biomechanics


Two positions for guest researchers(post-doc) at NIST on biomechanics

Research area: Biomechanics

Practical and graphical remarks about Moving Least Squares

I have had some time to write down an informal introduction to Moving Least Squares, from my coding perspective. It is supposed to be a condensation of experiences after some years of using it, although it does not contain any new theoretical aspect.

a fracture problem

  Dear everyone

Head loss in the laminar layer

Free Tags: 


I have a question which dealing with head loss in laminar flow. 

Is there another head loss formula except the Δh = f (l / dh) (v2 / g 2).

which the formula association of viscosity, length, wall shear stress, and diameter.

Any1 here can list out the head loss formula for me??

Thanks for the concern!

Understanding continuity

Worth reading

in case you need to explain the epsilon-delta  definition of continuity to an engineering student.

-- Biswajit 

fhuera's picture


The Department of Mechanical Engineering at the Universitat Rovira i Virgili (URV) ( in Tarragona (Spain), is looking for several enthusiastic research students with a strong interest in fluid dynamics. Successful candidates will join a small but very active multidisciplinary team, working in fluid-structure interaction problems. The research will be mainly experimental and focused in the area of fluid structure interaction with application to several engineering problems.

Mario Juha's picture


I would like to know why ABAQUS is the dominant FEM program (in terms of comments) in this forum? Why do you consider ABAQUS over ANSYS?

I have been using ANSYS for at least 8 years and I am very please with the capabilities of it. But I have not seen ABAQUS or used it. Beside, reading all the comments that are posted in imechanica, I feel like I am using the wrong FEM program. 

Which are the advantage of ABAQUS over ANSYS?


Thank you,

 Mario J . Juha

Modeling Nitinol


I'm new in this forum and I've a problem that i can't resolve.

I need to model nitinol in Abaqus: I've red the documentation and many topic in Internet but I don't understand if I must use a VUMAT subrutine or it is sufficent the tool of user defined material in Abaqus/CAE. I need something simple like an elastoplatic behaviour with hysteresis given by the different states of austenite and martensite.

Thanks in advance,


Open Call for Journal Club Themes and Discussion Leaders

Attention all iMechanicians!  If you have a theme you would like to see in the Journal Club next year, please feel free to:

  1. post it here for discussion
  2. send it to me via email
  3. reccommend discussion leaders

Thanks in advance!

Konstantin Volokh's picture

Journal Club Theme of September 2009: Elasticity and Failure

Let us consider interaction of two atoms/molecules/particles. The reference distance between them corresponds to zero interaction force and zero stored energy. The interaction passes three stages with the increase of the distance. At the first stage the force increases proportionally to the increasing distance: the linear stage. At the second stage the force-distance relationship deviates from the linear proportionality: the nonlinear stage. At the third stage the force drops with the increasing distance: the separation or failure stage.

16th US National Congress on Theoretical and Applied Mechanics

The Congress will be held on 27 June – 2 July 2010, at the Pennsylvania State University.  The deadline for submitting abstract is 15 October 2009.

Pradeep Sharma's picture

Revisiting Quantum Notions of Stress

I plan to submit the attached paper on quantum mechanical definition of stress in the next few weeks. Comments and feedback are welcome. Fair amount of work has been done on stress definition in the context of classical molecular dynamics (also attracting some controversies). In contrast, there appear to be several open issues in the quantum case. Hopefully, the attached paper provides a starting point.

tadmor's picture

Multiscale Postdocs at Minnesota

Several postdoc positions are available immediately at the University of Minnesota to work on the development of a variety of cutting edge multiscale methods and atomistic simulation techniques.  The work will be done in close collaboration with a group of leaders in the field including Prof. Ellad Tadmor, Prof. Richard James, Prof. Mitchell Luskin and Prof. Ryan Elliott.  For more information, visit or check out the attached announcement.

Jean H. Prevost's picture

Postdoctoral position at Princeton University

Postdoctoral position available at Princeton University to participate in a multi-disciplinary research project sponsored by the US Army Research Office (ARO/MURI) at Princeton and Harvard Universities on: Innovative Design of Multi-Functional Adaptive Structural Materials. The candidate will be involved in the Modeling of Hierarchically Porous Material Structures Optimized for Strength and Transport. The candidate must have a strong background in Finite Element Analysis (both solid and fluid), and in Topology Optimization.

3rd International Conference on Mechanics of Biomaterials & Tissues - program now available!

Program for the 3rd International Conference on Mechanics of Biomaterials & Tissues now available at

Plenary and keynote speakers include:

Professor Julian Vincent, Professor of Biomimetics, Bath University, UK
-Stiffness and toughness of biological materials


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