/MAT/LAW22 (DAMA)

Block Format Keyword

/MAT/LAW22 - Elastic Plastic with Damage Material

Description

This law is identical to Johnson-Cook material (/MAT/LAW2), except that the material undergoes damage if plastic strains reach a user-defined value (). This law can be applied to both shell and solid elements (see Comment 4 for note on solids).

Format

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
/MAT/LAW22/mat_ID/unit_ID or /MAT/DAMA/mat_ID/unit_ID
mat_title

E
a		b		n
c				ICC
		Et

Field	Contents	SI Unit Example
mat_ID	Material identifier (Integer, maximum 10 digits)
unit_ID	Optional unit identifier (Integer, maximum 10 digits)
mat_title	Material title (Character, maximum 100 characters)
	Initial density (Real)
E	Young’s modulus (Real)
	Poisson’s ratio (Real)
a	Yield stress - should be strictly positive. (Real)
b	Hardening parameter (Real)
n	Hardening exponent (Real)
	Failure plastic strain Default = 1030 (Real)
	Maximum stress Default = 1030 (Real)
c	Strain rate coefficient Default = 0.00 (Real) = 0: no strain rate effect
	Reference strain rate If , no strain rate effect (Real)
ICC	Strain rate computation flag (Comment 2) (Integer) = 0: default set to 1 = 1: strain rate effect on = 2: no strain rate effect on
	Damage model starts at Default = 0.15 (Real)
Et	Softening damage slope () Default = 0.00 (Real)

#RADIOSS STARTER

#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|

/UNIT/1

unit for mat

g mm ms

#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|

#- 2. MATERIALS:

#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|

/MAT/DAMA/1/1

Aluminum

# RHO_I

.0027

# E NU

70000 .3

# a b n EPS_max SIGMA_max0

100 0 1 .2 100

# c EPS_dot_0 ICC

0 0 0

# EPS_dam E_t

.1 -2000

#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|

#ENDDATA

/END

#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|

1.	Damage is isotropic, its effect are the same in tension and compression.

Where, is the plastic strain and is the strain rate.

2.	ICC is a flag of the strain rate effect on material maximum stress .

mat_law27

3.	The damage appears in the material when the strain is larger than a maximum value :

If , Law 22 is identical to law /MAT/LAW2.

clip0053

4.	For solid elements, the damage law can only be applied to the deviatoric stress tensor sij and .

5.	When reaches in one integration point, then based on the element type:

•	Shell elements: The corresponding shell element is deleted.

•	Solid elements: The deviatoric stress of the corresponding integral point is permanently set to 0, however, the solid element is not deleted.

/MAT/LAW22 (DAMA)

/MAT/LAW22 (DAMA)

/MAT/LAW22 (DAMA)

See Also: