research

An efficient computational technique for modeling dislocation–precipitate interactions within dislocation dynamics

Submitted by keyhani on Sun, 06/12/2016 - 01:07

A new computational technique for modeling dislocation interactions with shearable and non-shearable precipitates within the line dislocation dynamics framework is presented. While shearable precipitates are modeled by defining a resistance function, non-shearable ones are modeled by drawing a comparison between the two well-known Orowan and Frank–Read mechanisms. The precipitates are modeled directly within the dislocation dynamics analysis without the need for any additional numerical methods.

Electrical properties and piezoresistive evaluation of polyurethane-based composites with carbon nano-materials

Submitted by Hamid Souri on Thu, 06/09/2016 - 05:26

research

Expanded graphite; Graphite nanoplatelet; Three-roll milling process; Electrical characteristics; Piezoresistivity; Polyurethane; Composite

The present study assesses the applicability of carbon materials-embedded polyurethane (PU) composites characterized by high piezoresistive capability, as a traffic loading sensor. PU composites incorporating multi-wall carbon nanotubes (MWNTs), expanded graphite (EG), and a hybrid of MWNTs and graphite nanoplatelets (GNPs) were fabricated and their electrical conductivities were measured in an effort to determine the most suitable filler type for the piezoresistive sensor and its optimum content ratio.

A facile method for transparent carbon nanosheets heater based on polyimide

Submitted by Hamid Souri on Thu, 06/09/2016 - 05:23

research

Thin film heater; Polyimide; Transparent

In this work, a novel film heater in nanometer-scale thickness based on catalyst-free and transfer-free carbon nanosheets (CNSs) with properties similar to graphene is fabricated. Here, poly(amic acid) (PAA), which is composed of several aromatic hydrocarbon rings, is used as the carbon precursor of CNS films. Altering the polymer concentration easily controls the morphological, optical, and electrical properties of the CNS films obtained by carbonization of PAA thin films.

Search engine for postdoc or faculty posiotn in USA

Submitted by r_n_s_s on Tue, 06/07/2016 - 09:36

research

What is best way to seach for postdoctoral position or faculty position in USA?

I am aware that in iMechanica some positions are posted but the number of positions is limitted. I would appriciate any advice from people in the US. Thanks!

Regards,

A critical thickness condition for graphene and other 2D materials

Submitted by Harley T. Johnson on Mon, 06/06/2016 - 20:14

B. C. McGuigan, P. Pochet, and H. T. Johnson, Critical thickness for interface misfit dislocation formation in two-dimensional materials, Phys. Rev. B 93, 214103, 2016.

URL: http://link.aps.org/doi/10.1103/PhysRevB.93.214103

draw the mass gain curve over time

Submitted by vanos1989 on Fri, 06/03/2016 - 11:04

research

Hello

I want to draw the mass gain curve over time, it follows the Fick law but the results I obtained are either instantaneous or ramp.

how to draw?

thank you

Square to parallelogram

Submitted by addlona on Thu, 06/02/2016 - 17:44

research

I am trying to model a rigid box which deforms into a parallelogram on application of

displacement/velocity. I have made a box using 4 rigid plates ,but when I apply

the shear force the plates lose contact. I have used no seperation technique

it didn't help .kindly give a solution asap.

Fillet Weld in ABAQUS

Submitted by ACSU on Thu, 06/02/2016 - 01:21

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Hello everyone,

I want to model a connection between two steel plates which form a T-section. The welds are fillet weld. Do you have any recommendation how to model the weld? One way I think of is to connect the two plates with two solid elements weld through tie constraint. You think that's a right way of doing that?

Excessive rotation of Nodes/ ABAQUS explicit

Submitted by soheil.tahmasbi on Thu, 06/02/2016 - 00:37

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I am simulating dynamic impact using B31 element type and general contact in ABAQUS Explicit and the job is aborted showing the error of "Excessive rotation of nodes". I, also, used mass scaling to control the run time.
Does anyone know how to control this problem?

I really appreciate your replies.