Command manual

Command list

PROP_DAMAGE_JC

Material properties
*PROP_DAMAGE_JC
"Optional title"
did, erode, noic
$d_1$, $d_2$, $d_3$, $d_4$, $d_5$, $\epsilon_0$, $T_0$, $T_m$
$\epsilon_{min}$

Parameter definition

VariableDescription
did Unique damage identification number
erode Element erosion flag
options:
0 $\rightarrow$ failed element is not eroded
1 $\rightarrow$ failed element is eroded
2 $\rightarrow$ node splitting at failure (crack plane orthogonal to max principal strain)
3 $\rightarrow$ node splitting at failure (crack plane orthogonal max principal stress)
noic Flag to turn off cracking along interface between different materials
options:
0 $\rightarrow$ material interface cracks are allowed
1 $\rightarrow$ material interface cracks are not allowed
$d_1$, $d_2$, $d_3$, $d_4$, $d_5$ Damage parameters
$\epsilon_0$ Reference strain rate
default: 1
$T_0$, $T_m$ Reference and melting temperatures
$\epsilon_{min}$ Minimum failure strain
default: 0

Description

This is the Johnson-Cook failure criterion. The material will lose its shear strength pressure once the damage parameter, $D$, has evolved from 0 to 1. The damage growth rate is defined as:

$\displaystyle{\dot D = \frac{\dot\epsilon_{eff}^p}{\mathrm{max}(\epsilon_{min}, \epsilon_f)}}$

where:

$\displaystyle{ \epsilon_f = (d_1 + d_2 \cdot \mathrm{e}^{\frac{\vert d_3 \vert \, p}{\sigma_{eff}}}) \cdot (1 + d_4 \cdot \mathrm{ln}(\frac{\dot\epsilon_{eff}^p}{\epsilon_0})) \cdot (1 + d_5 \cdot (\frac{\mathrm{T}-\mathrm{T}_0}{\mathrm{T}_m - \mathrm{T}_0}))}$

and:

$p = -(\sigma_{xx} + \sigma_{yy} + \sigma_{zz})/3$