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Hidroxid's picture

Assigning crystal plasticity material constants for one crystal with more than one element (default of Dr Huangs model)



I am just a beginner in Abaqus UMAT and I have started working with Dr Huang's crystal plasticity UMAT in Abaqus.

When I am assigning one material constants for one element crystal it works but when I try to assign it to more than one element for one crystal (for example group of elements with same grain orientation) it give me error code 144.

Can anybody explain me the reason?



Thanks in advance,

Kind regards,



CTE: coefficient of thermal expansion - Secant Method - Ansys

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I have to perform a thermo-mechanical simulation in Ansys WB and I have to provide the cte of a material.

I have few experience with thermo-mechanical simulation.

I have got a document with the material properties of this material; there I have the Tg (glass transition temperature)

and two coefficients: cte1 (below Tg) and cte2 (above Tg).


-->  How should I calculate the CTE for a temperature range (e.g. -50 < Tg < 300) ?   <---


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bitamendi's picture

Looking for a VUMAT programmer to share publication with

Dear researchers,


I’m Joseba Mendiguren, researcher at the Advanced Manufacturing Group of Mondragon Unibertsitatea. I’m currently working on advanced yielding/hardening models for metals.
I’m in the middle of a paper writing work but I cannot find time to sit down and program the VMAT that I need to run some simulations for the paper. I’m looking for a VUMAT programmer researcher willing to work on the topic and share the publication authorship on return.

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Dynamic response and localisation in strongly damaged waveguides

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The elastic rod assumes the form of a liquid drop at self-encapsulation!
Enjoy the dripping of an elastic rod at

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Link to the article published in Acta Materialia: (Free access for 50 days)

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The edge effect in open lipid bilayers


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The derivation is based on the interactions of the molecules comprising the edge.

The derived model can be employed to study pore growth in open lipid bilayers.

The model captures bending and torsional energies of the edge, in addition to the line tension.

The molecular origins of spontaneous curvatures and elastic moduli are investigated.

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With funding from the Haythornthwaite Foundation, the Executive Committee (EC) of the Applied Mechanics Division (AMD) of ASME is pleased to announce the establishment of the Haythornthwaite Research Initiation Grant Program, targeting university faculty engaged in research in theoretical and applied mechanics that are at the beginning of their academic careers. Applicants must hold a tenure-track appointment at the rank of Assistant Professor at a US university on October 1, 2015, and must not be more than 5 years beyond receipt of their doctoral degree at the time the award is made.

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Dear all,

I have recently using the subroutine FRIC in ABAQUS, and I found that there is a variable 'PRESS' which is specified as 'contact pressure at end of increment' in the ABAQUS documentations. However, I have extracted this PRESS in a text file through applying the subroutine FRIC in a two-block compression model, and I found that the PRESS is different from the contact pressure (CPRESS) which can be obtained from the field output and it seems that there are two values in each simulation increment.

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Could you please tell me how to create a *Beam General Section(abaqus) for triangular element with all sieds are equal.



ASME Applied Mechanics Division Seeks Nominations for Awards

The Applied Mechanics Division, of the American Society of Mechanical Engineers, seeks nominations for the awards listed below. All the awards are international. Neither the nominee nor the nominator need be a member of the ASME. However nominators must not be active members of the respective award committees. Further descriptions of the awards are given at A PDF version of this announcement can be found as an attachment at the end of this blog entry.

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Shu Yang1 and Jie Yin2

1Department of Materials Science and Engineering, University of Pennsylvania, E-mail:

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The Computational Mechanics group at The University of Iowa, led by Professor S. Rahman, is looking for new Ph.D. students, who are capable of and interested in performing high-quality research on engineering design. The research, supported by National Science Foundation and others, entails building a solid mathematical foundation, devising efficient numerical algorithms, and developing practical computational tools for stochastic design optimization. A substantial background in solid mechanics and structural optimization is a must; exposures to stochastics and probabilistic methods are highly desirable.

If you are interested in pursuing a Ph.D. degree at Iowa, please contact and send a resume to: Professor Sharif Rahman at Please note that we are interested in students who already have M.S. degrees in engineering or mathematics. The desired start date is Spring 2016 or sooner.


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