Learning Forum

[VictorKats]

I am a grad student using Explicit Dynamics to study the crashworthiness of certain structures. I am currently using the Johnson-Cook model to simulate the response of a SS304 structure which suffers an impact at 10m/s. Due to the relatively high strain rates, the material would heat up affecting the material properties locally, and the J-C equation should take into account the temperature. My question is, is Explicit Dynamics calculating the energy dissipation using the material density, specific heat and integrating flow stress over plastic strain to compute the temperature increment locally at each node and including this thermal softening within the simulation? Or is it neglecting the temperature increase?

Thank you for your help,

Victor Bautista 

[Akshay Maniyar]

Specific heat capacity must be defined to enable the calculation of temperature for thermal softening effects. You cab refer to the below link for more details about the Johnson cook strength model.
regards amaniyar

[VictorKats]

Thanks for your response! I have the specific heat capacity defined within the material properties. I didn't see any link in your comment. Could you reupload it? It would be very helpful. Thanks!

Best victor

[Tetescu]

Which J-C formulation are you asking about? If using 224, you need to define the thermal behavior. The guidelines for MAT_224 can be found on the LS-DYNA Aerospace Working Group.