# research

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

Hi!

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?

Kind regards,

Omid

## CTE: coefficient of thermal expansion - Secant Method - Ansys

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Hello,

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) ?   <---

## 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.

## Fluid flow across a cylinder kept an angle with vertical

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Hello,

## Clarification on creep

Hello,

My work is related to creep in ceramics. Often I find the relation between the creep strain rate and stress as:

creep_strain_rate = constant x stress x other_factors                  (1)

"stress" is a general term here. Sometimes this relation (1) is applied along the principal stress direction; stress then refers to principal stress. In other cases stress is used to represent the effective stress which is expressed as following (not sure if this is complete/correct definition):

## Can an elastic rod attain self-encapsulation when loaded transversally at midspan?

Can an elastic rod attain self-encapsulation when loaded transversally at midspan?

The elastic rod assumes the form of a liquid drop at self-encapsulation!
Enjoy the dripping of an elastic rod at
http://www.ing.unitn.it/~bigoni/dripping.html

## Phase-field simulations of non-cooperative eutectoid transformation proceeding from polycrystalline austenite in Fe-C steels

Link to the article published in Acta Materialia: http://authors.elsevier.com/a/1RMRv_UwYsChmK (Free access for 50 days)

K. Ankit, R. Mukherjee, B. Nestler. Deviations from cooperative growth mode during eutectoid transformation: Mechanisms of polycrystalline eutectoid evolution in Fe–C steels. Acta Materialia 97 (2015) 316–324.

## Regarding the ABAQUS Subroutine 'FRIC'

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.

## Postdoc opening in design optimisation at the University of California, San Diego

The Multiscale and Multiphysics Design Optimization Group at the University of California, San Diego, is looking for a Postdoc. The research will develop numerical methods in coupled multiphysics and multiscale topology optimisation in aircraft in a modularized and parallel computing environment. It is expected that the applicants would have background in topology optimization or level set method, aeroelasticity, computer programming and computational mechanics.

## *BEAM GENERAL SECTION

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Hi

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

Ravi

## Opening for new Ph.D. students in the Computational Mechanics group, The University of Iowa.

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 sharif-rahman@uiowa.edu. 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.