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Johnson Cook Model

User material subroutine for Johnson Cook Model in LS DYNA

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I need to edit user subroutine for existing Johnson Cook model (MAT_015) in LS DYNA. I have downloaded object files. However, I could not find any subroutine file for MAT_015. I need to edit the model and add 2 more parameters to increase its accuracy. Creating it from scratch is really a lengthy task. Can anyone help me in this regard? Thank you. 

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Can I use the Johnson-Cook method to capture and predict fiber failure of a composite material?

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Is it possible to use a Johnson-Cook method to predict the fiber damage in a composite lamina? I am presently using ABAQUS for it. I want to capture fiber failure.

Plotting the Johnson-Cook strength model

I'm trying to plot the stress-strain curve described by the Johnson-Cook strength (and eventually damage) models. The strength model is defined as:

σ=[A+Bεn][1+C ln(ε_dot*)][1-T*m]

where A, B, C, n, and m are material constants, ε_dot* is the non-dimensionalized strain rate, and T* is the homologous temperature where T*=(T-T0)/(Tmelt-T0)

To calculate the thermal softening (term in the last bracket of the J-C model), I need to determine the increase in temperature related to an increase in stress (and strain). I'm using the following equation:

AISI 4150 or DIN 50CrMo4 Steel Flow Stress Curve Data for Machining Simulation

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Hi All,

I am into machining simulation of 50CrMo4 Steel in DEFORM 3D and I need the flow stress curve data for various temperature and various strain rates. I have searched in as many journals as possible, but in vain. It would be of immense help if some one could share the material model data with me.

Thanking you in advance

With Best Regards

Ashwin Devotta 

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