*MAT_124 (PLASTICITY_COMPRESSION_TENSION)

LS-DYNA Input Interface KeywordDefines an isotropic elasto-plastic material with tension and compression yield stress curves as a function of plastic strain.

Rate effects are modeled by Cowper-Symonds models or by curves. Additional viscosity can be defined by Prony series Maxwell model.

Format

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)
MAT_124 or MAT_PLASTICITY_COMPRESSION_TENSION
`mat_ID`	$ρ_{i}$ $ρ_{i}$	`E`	$ν$ $ν$	`C`	`P`	`FAIL`
`fct_ID`_c	`fct_ID`_t	`Frate_ID`_c	`Frate_ID`_t	`VP`	`Fct_LCFAIL`	`Ec`	`RPCT`
`P_c`	`P_t`			`PCUTF`			`F_smooth`
`Kv`
`Gi`	`BETAi`

Definition

Field	Contents	SI Unit Example
`mat_ID`	Material identifier. (Integer)
$ρ_{i}$ $ρ_{i}$	Initial density. (Real)	$[\frac{kg}{m^{3}}]$ $[\frac{kg}{m^{3}}]$
`E`	Young’s modulus. (Real)	$[Pa]$ $[Pa]$
$ν$ $ν$	Poisson’s ratio. Default=0 (Real)
`C`	Cowper-Symonds strain rate coefficient. (Real)	$[Pa]$ $[Pa]$
`P`	Cowper-Symonds strain rate exponent. (Real)	$[Pa]$ $[Pa]$
`FAIL`	Plastic strain to failure. (Real)
`fct_ID`_c	Curve identifier for compression yield stress. (Integer)
`fct_ID`_t	Curve identifier for tension yield stress. (Integer)
`Frate_ID`_c	Curve identifier defining the scaling coefficient for compression yield stress. (Integer)
`Frate_ID`_t	Curve identifier defining the scaling coefficient for compression yield stress. (Integer)
`VP`	Strain rate formulation flag. = 1 (Default) Total strain rate. = 2 Plastic strain rate. (Integer)
`Fct_LCFAIL`	Curve identifier defining plastic strain at failure as a function of strain rate. (Integer)
`Ec`	(Optional) Compression Young’s modulus. (Real)
`RPCT`	Scale factor used on `P_c` and `P_t`. (Real)
`P_c`	Limit pressure in compression. (Real)	$[Pa]$ $[Pa]$
`P_t`	Limit pressure in tension. (Real)	$[Pa]$ $[Pa]$
`PCUTF`	Pressure limit activation flag. = 0 Not active = 1 Active No default (Integer)
`F_smooth`	Exponential moving average strain rate filtering value (defined between 0 and 1). (Real)
`Kv`	Viscous bulk modulus. (Real)	$[Pa \cdot s]$ $[Pa \cdot s]$
`Gi`	Shear relaxation modulus. (Real)	$[Pa]$ $[Pa]$
`BETAi`	Shear decay constant. (Real)	$[\frac{1}{s}]$ $[\frac{1}{s}]$

Comments

This keyword maps to /MAT/LAW66, /VISC/PRONY and failure model (/FAIL).
This material can be used for shell or solid elements.
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.