metal

Bridge failures underscore the importance of rigorous material testing. The collapse of the incomplete pedestrian bridge at Florida International University on March 2018 is an example where design errors led to growing cracks as described by OSHA.

Although material failure is not the sole reason for bridge failures, it is a crucial step for selecting the right materials, bridge design analysis, and construction testing.

The PIMM lab is looking for a postdoctoral researcher to work in a joint project with CNES (French space agency), on the design of architectured materials through additive manufacturing.

Although in French, the link hereafter is available for application, even for non-French speaking candidate.

https://cnes.fr/fr/les-ressources-humaines-du-cnes/conception-et-optimisation-de-materiaux-architectures-pour

A colleague of mine wants to find a visiting position on research of fracture mechanics of metals.  His visit is supported by a grant from his institution and he is interested in working with someone on fracture mechanics of metal materials.  Please drop me a line and I shall help you connected.  

Dear all,

I would like to run a tensile test under ls-dyna of a mild steel  and
apply a 7000 N load to the dog bone specimen on a explicite scheme.

Unfortunately, I
have wild deformations ( and an error) on the nodes on edges where the
load is applied, so can you please tell me what are the importants
constants (like time termination, mass scale,...) and how to perform a
perfect run?

Have a good day,

Thank you

M.

Hi,

I am searching on multiscale simulation of polymer/metal ( mechanical propertices).

Cohesive zone model is used for this porpose.

Is there another models that can use for this issue and using MD data as input?

Best regards,

Hamed

Determination of Strain Gradient Elasticity Constants for Various Metals, Semiconductors, Silica, Polymers and the (Ir) relevance for Nanotechnologies

Strain gradient elasticity is often considered to be a suitable alternative to size-independent classical elasticity to, at least partially, capture elastic size-effects at the nanoscale. In the attached pre-print, borrowing methods from statistical mechanics, we present mathematical derivations that relate the strain-gradient material constants to atomic displacement correlations in a molecular dynamics computational ensemble. Using the developed relations and numerical atomistic calculations, the dynamic strain gradient constants have been explicitly determined for some representative semiconductor, metallic, amorphous and polymeric materials. This method has the distinct advantage that amorphous materials can be tackled in a straightforward manner. For crystalline materials we also employ and compare results from both empirical and ab-initio based lattice dynamics. Apart from carrying out a systematic tabulation of the relevant material parameters for various materials, we also discuss certain subtleties of strain gradient elasticity, including: the paradox associated with the sign of the strain-gradient constants, physical reasons for low or high characteristic lengths scales associated with the strain-gradient constants, and finally the relevance (or the lack thereof) of strain-gradient elasticity for nanotechnologies.