*MAT_006 (VISCOELASTIC)

LS-DYNA Input Interface KeywordThis keyword defines an isotropic, visco-elastic material. It is generally used to model incompressible rubbers, polymers, foams, and elastomers.

Format

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)
*MAT_006 or *MAT_VISCOELASTIC
mat_ID	${\rho }_i$	K	G0	G_INF	BETA

Definition

Field	Contents	SI Unit Example
mat_ID	Material identifier. (Integer)
${\rho }_i$	Initial density. (Real)	$\left[\frac{\text{kg}}{{\text{m}}^{\text{3}}}\right]$
K	Bulk coefficient. (Real)	$\left[\text{Pa}\right]$
G0	Short time shear modulus. (Real)	$\left[\text{Pa}\right]$
G_INF	Long time shear modulus. (Real)	$\left[\text{Pa}\right]$
BETA	Decay coefficient. (Real)	$\left[\frac{\text{1}}{\text{s}}\right]$

Comments

1. This keyword maps to /MAT/LAW34 (BOLTZMAN). It is compatible with truss, beam shell and solid elements.
2. Parameters K, G0, and G_INF are required.
3. Input of material parameters as a function of temperature is not supported.
4. 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.