Learning Forum

[Adisa]

Hi, I have read this:

 https://www.researchgate.net/post/What_is_the_difference_between_static_and_dynamic_impact_strength

And know, I am interested in how to calculate dynamic factor and get dynamic stress which will be the ultimate stress. The dynamic stress I need  because I am doing shpere test in transient structural, So far I did not use dynamic stress for this type of the analysis. I am using the total strain as criteria break. how I need to use dynamic stress or maybe dynamic strain in this type of analysis, drop test.

[Ashish Khemka]

Hi Adisa,

 

I did not see any guideline in our documentation for this.

 

Regards,

Ashish Khemka

[peteroznewman]

Hi Adisa,

The title of your post asks a question. In the context of ANSYS, there is no such thing as dynamic impact strength.

The body of your post says you are doing a ball drop test in Transient Structural and you will compare the Total Strain with Elongation at Break to decide when failure has occurred. This is a good start. The question is what material properties are you using?

Some materials exhibit a significant sensitivity to strain rate. That means the material may have a low stiffness and a large Elongation at Break for low strain rates, and a high stiffness and a small Elongation at Break for high strain rates.

You can explicitly model strain rate in the Anand Viscoplasticity material model, which I added to a Nylon 6/6 material. I don't know how to use this material model, I just show it as an example of how strain rate can be included in the model.

Regards,

Peter