research

For more than 15 years, carbon nanotubes (CNTs) have been the flagship material of nanotechnology. Researchers have conceived applications for nanotubes ranging from microelectronic devices to cancer therapy. Their atomic structure should, in theory, give them mechanical and electrical properties far superior to most common materials.  

Hi,

Iam a new user of abaqus. I have a subroutine written in *.for format. I also have an input file *.inp . Both these programs are in the same folder. When I try to execute the *.inp file using the command

abaqus job=jobname datacheck interactive

I get a  message saying  "Abaqus/Standard Analysis exited with an error. please see the message file for possible error messages". I looked in the message file and it says ***ERROR: USER SUBROUTINE UMAT IS MISSING.

Then I used the command

abaqus job=jobname user=umat.for

This is suneel donthamsetty working on metal matrix nanocomposites.i want to analyse aluminium matrix (Sic reinforced)nanocomposites using Ansys software.which type of element is suitable for nanoparticles.can any body answer please.

I need help to determine or contruct the crack reistance (R-curve) of a material that show crack bridging. I have the experimental data of applied load and crack lengths due to these applied loads. the SENB specimen was used and loading was 4-pt-bending. The plot of Kapp versus crack size did not give the usual rising curve which plateaus, but rather increases exponentially. How do I get the Kb (i,e K due to bridging) or the normal R-curve. I am not a mechanical engineer but into applied mechanics.

We have read some papers of stroh formalism and the textbook of Tom Ting, and found that the stroh formalism and the hamilton system proposed by prof.zhong wanxie had some relation. We want to know whether the stroh formalism is enough for the analysis of the anisotropic elastic? Thus's to say, for some problems could not  give the satisfied answer which we may try the hamilton framework. I briefly compare the two methods as follows:

This paper revisits continua with microstructure from a geometric point of view. We model a structured continuum as a triplet of Riemannian manifolds: a material manifold, the ambient space manifold of material particles and a director field manifold. Green-Naghdi-Rivlin theorem and its extensions for structured continua are critically reviewed.