RD-V: 0200 Hardening Modulus

The plastic hardening modulus is evaluated in a Johnson-Cook material.

図 1.

The /MAT/LAW2 (PLAS_JOHNS) material model is used to study the plastic hardening modulus of a material.

Options and Keywords Used


Input Files

The following input file is used in this example:


Model Description

Problem #1 1 is simulated in Radioss.

A tensile loading is applied to a cube with side lengths 25.4 mm. The bottom of the cube is fixed in the z-direction and an imposed velocity of 508 mm/s in the z direction is applied to the top of the block. The simulation was run to a final time of 0.05 seconds. A two elements per side mesh was studied.

The plastic hardening modulus, H, is used as the problem metric. In Radioss, the plastic hardening parameter, b, in /MAT/LAW2 (PLAS_JOHNS) material law is the same as the plastic hardening modulus, H.

The following system is used: mm, s, Mg.


The plastic hardening modulus is the slope of the stress versus plastic strain curve.

図 2. Stress versus Plastic Strain with Hardening Modulus


As shown in 図 2, the hardening modulus from the simulation, H=794.225 Mpa, exactly matches the value input for “b” in /MAT/LAW2 (PLAS_JOHNS).

1 Buechler, Miles, Amanda McCarty, Derek Reding, and R. D. Maupin. "Explicit finite element code verification problems." In 22nd SEM International Modal Analysis Conference, Dearborn, MI. 2004.