2023.1

2023.1

*MAT_099 (SIMPLIFIED_JOHNSON_COOK_ORTHOTROPIC_DAMAGE)

LS-DYNA Input Interface KeywordDefines an an isotropic elasto-plastic material using the Johnson-Cook material model.

Format

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)
MAT_098 or MAT_SIMPLIFIED_JOHNSON_COOK_ORTHOTROPIC_DAMAGE
`mat_ID`	$ρ_{i}$	`E`	`ν`		$ε_{p}^{m a x}$
`a`	`b`	`n`	`c`	`FAIL`	$σ_{\max 0}$		${\dot{ε}}_{0}$

Definition

Field	Contents	SI Unit Example
`mat_ID`	Material identifier. (Integer)
$ρ_{i}$	Initial density. (Real)	$[\frac{kg}{m^{3}}]$
`E`	Young’s modulus. (Real)	$[Pa]$
`v`	Poisson’s ratio. Default = 0 (Real)
$ε_{p}^{m a x}$	Failure plastic strain. Default = 10³⁰ (Real)
`a`	Yield stress. (Real)	$[Pa]$
`b`	Hardening coefficient. (Real)	$[Pa]$
`n`	Hardening exponent. (Real)
`c`	Strain rate coefficient. (Real)
`FAIL`	Principal plastic strain to failure. (Real)
$σ_{\max 0}$	Maximum stress limit. (Real)	$[Pa]$
${\dot{ε}}_{0}$	Reference strain rate. (Real)	$[\frac{1}{s}]$

Comments

This keyword maps to /MAT/LAW2 (PLAS_JOHNS) and /FAIL/FLD.
The option “_TITLE” can be added to the end of this keyword. When “_TITLE” is included, an extra 80 characters long line is added after the keyword input line which allows an entity title to be defined.