*MAT_252 (TOUGHENED_ADHESIVE_POLYMER)

LS-DYNA Input Interface KeywordThis is a non-associated elasto-plastic model for polymer adhesives.

The constitutive model is based on I1-J2 criterion that can be reduced to von Mises or Drucker-Prager type in compression.

Format

(1) (2) (3) (4) (5) (6) (7) (8)
*MAT_252 or *MAT_TOUGHENED_ADHESIVE_POLYMER
mat_ID ρ i E NU Iform Itrx Idam
Table_ID Tau_0 Q Beta H C Epsd_ref Epsd_max
AF1 AF2 AH1 AH2 AS Exp_n
D1C D2C D1F D2F DTRX DJC

Definition

Field Contents SI Unit Example
mat_ID Material identifier.

(Integer)
ρ i Initial density.

(Real)

 [ kg m 3 ]
E Elastic modulus.

(Real)

 [ Pa ]
NU Poisson’s ratio.

(Real)
Iform Yield criterion formulation.
= 0
Drucker-Prager model in compression.
= 1
von Mises model in compression.

(Integer)
Itrx Damage dependency on triaxiality in compression flag.
= 0
Damage depends upon triaxiality only in tension.
= 1
Damage depends upon triaxiality in both tension and compression.

(Integer)
Idam Strain rate definition in damage model flag.
= 0
Damaged plastic strain rate is used.
= 1
Undamaged plastic strain rate is used.

(Integer)
Table_ID Table identifier to define yield stress as a function of plastic strain, strain rate and temperature.

(Integer)
Tau_0 Initial yield stress.

(Real)

 [ Pa ]
Q Voce hardening modulus.

(Real)

 [ Pa ]
Beta Voce nonlinear hardening modulus.

(Real)
H Linear hardening exponent.

(Real)

 [ m ]
C Johnson-Cook strain rate coefficient for hardening .

(Real)
Epsd_ref Quasi-static threshold strain rate in Johnson-Cook term.

(Real)

 [Hz]
Epsd_max Maximum dynamic threshold strain rate in Johnson-Cook term.

(Real)

 [Hz]
AF1, AF2 Yield function parameter.

(Real)
AH1, AH2 Yield function distortional hardening parameter.

(Real)
AS Plastic flow function parameter for hydrostatic term.

(Real)
Exp_n Exponential coefficient for damage strain rate dependency.

(Real)
D1C, D2C Johnson-Cook parameter for damage initiation.

(Real)
D1F, D2F Johnson-Cook parameter for failure strain.

(Real)
DTRX Johnson-Cook damage parameter for triaxiality term.

(Real)
DJC Johnson-Cook strain rate parameter for damage.

(Real)

Comments

  1. This keyword maps to /MAT/LAW120 (TAPO).
  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.