RADIOSS loading&unloading

Marta Palenzona

Hi everyone,

I have to run a simulation of a tensile test specimen (dog bone) which is subjected to a load-unload condition.

The specimen is in TPO.

I've tried some different material law (i.e. M38, M65) but noone fit the experimental curve. 

Could someone help me?

Thanks in advance.

Marta

Adriano A. Koga

Can you provide more information about your issue?

Maybe some graphs for your experimental and numeric curves. I think this would make it easier for everyone to understand what are you facing.

 

What about using HyperStudy to fit your data? Are you familiar with it?

There are a few tutorials for material calibration.

 

 

Marta Palenzona

Hi Adriano, I answer the last question first: I'm not familiar with HyperStudy, I alwayse use Hypermesh and Radioss.

About the simulation: I have made the laboratory material characterization, both the standard tensile test and three ciclical tests with load and unload, at different %strains.  I'd like to run a simulation of a specimen, reproducing the lab test, to verify the rightness of card material. This because I'll need to simulate a real plastic part which is subjected to a load-unload condition.

To date I've try M38 and M65 but the fit is not adequate. How can I perform it?

I've attached also the HM model  

Thanks

Marta Palenzona

@Adriano A. Koga, could you help me?

Could someone help me?

Adriano A. Koga

Marta Palenzona said:

@Adriano A. Koga, could you help me?

Could someone help me?

i'm not expert in Radioss, so I'm not quite sure what is the best option for you. Is it metallic part??

For metallic parts you could use LAW2 Johnson Cook and fit your data using the A, B, n parameters.

Or you could provide the material curve as LAW36 (piecewise curve).

 

Both of them support strain rate inputs as well.

But it would be nice if you can share the curves of your test and FE model so that others can look and try to understand what kind of behavior you're trying to reproduce.

 

HyperStudy tutorials shared up here would be helpful as well to fit data.

Marta Palenzona

@Adriano A. Koga, no, it's a plastic material. All law support strain rate input but my curves are %strain depentent. Could you involve someone expert in Radioss?

I've provide curves and FE model (.hm) in the reply above.