*MAT_018 (POWER_LAW_PLASTICITY)

LS-DYNA Input Interface KeywordThis model expresses isotropic plasticity model with rate effects which uses a power law hardening.

Format

(1) (2) (3) (4) (5) (6) (7) (8)
*MAT_018 or *MAT_POWER_LAW_PLASTICITY
mat_ID ρ i E v K N c p
SIGY VP ε p m a x          

Definition

Field Contents SI Unit Example
mat_ID Material identifier.

(Integer)

ρ i Initial density.

(Real)

[ kg m 3 ]
E Young’s modulus.

(Real)

[ Pa ]
v Poisson’s ratio.

(Real)

K Yield stress.

(Real)

[ Pa ]
N Plasticity hardening exponent.

Default = 1.0 (Real)

[ Pa ]
c Strain rate coefficient.
= 0 (Default)
No strain rate effect.

(Real)

[ 1 s ]
p Strain rate exponent.

Default = 1.0 (Real)

SIGY Optional yield stress value.

(Real)

[ Pa ]
VP Formulation for rate effects:
= 0
Total strain rate.
= 1
Viscoplastic strain rate.

(Integer)

ε p m a x Plasticity maximum stress.

Default = 1030 (Real)

Comments

  1. This keyword maps to /MAT/LAW44 (COWPER) + /FAIL/JOHNSON.
  2. 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.