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Have any one here worked on the effect of porosity and holes size on the mechanical properties, inclduing tear stregth of a film? I have a porous polyethylene film and I need to know what is the effect of holes size on the non-linear properties, such as tear strength, for a fixed porosuty of 40%. The filmthickness is about 10-20um. The hole size varies from 100 nm to 1 um to 10 um to 100um and higher.

Thanks,

FR 

As far as I am concerned ABAQUS considers viscosity effect on stress wave propagation in ABAQUS/Explicit by defining two parameters such as linear and quadratic bulk viscosity. By increasing viscosity, we get smooth stress propagation, but with energy dissipation. However, I am looking for a way to switch off viscosity effect and compare the results with analytical method in which pure elasticity is considered without any viscousity. Kindly let me know if you have any idea, Thanks in advance.

Good evening, how the potential energy 'PI' is formulated for CST and axisymmetric problems. i am much interested in the first part i.e. Pi= S.E. + W.P. How the triple integral is written in case of axisymmetric problems. How the work potential is formulated in case of both CST and Axisymmetric problems subjected to Traction force. ANY REFERENCE LINK OR VIDEOS ARE MUCH APPRECIATED. The derivation and obtaining stiffness matrix is not my importance.

When we only have mechanical loading, I understand that abaqus calculates the total deformation gradient using F = I + partial_U/partial_X and U = N_i*U_i where U_i is the displacement at the nodes  and N is the shape function .

If I use a thermal expansion in addition to mechanical loading , Does abaqus give the total deformation gradient incorporating both mechanical loading and  thermal expansion ?
F = I + partial_Utot/partial_X ; Utot = U_mechanical + U_thermal

In a CT fracture characterization test, Since we neglect data beyond a certain crack length (due to onset of considerable plasticity),

How can I delete a comment that was added wrongly?  Thank you!

Dear Friends,

I wrote a VUHARD for a dynamic explicit analysis. Something is going really very strange:

For a model with just a few elements it works,

But:

For the same model with finer mesh it is encountered to ''Element Excessive Distortion'' !!

Does anybody have any idea about that?

I would be happy to let me know.

Greetings,
Hassan

Does anyone have any helpful information (Organised governing equations & subroutine files) about Two & Three surface models which are developed by Shen & Goto respectively? 

I'm trying to run a material model (FORTRAN code) outside of ABAQUS, but it's a challenge, do you have any example or document may help?

Hello,