MATX02

Bulk Data Entry

MATX02 – Material Property Extension for Johnson-Cooke Elastic-plastic Material for Geometric Nonlinear Analysis

Description

Defines additional material properties for Johnson-Cooke elastic-plastic material for geometric nonlinear analysis. This is an elasto-plastic law with strain rate and temperature effects.

Format

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
MATX02	MID	A	B	N	EPSMAX	SIGMAX	C	DEPS0
	ICC	FSMOOTH	FCUT	M	TMELT	RCP

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
MAT1	102	60.4		0.33	2.70E-06
MATX02	102	0.09026	0.22313	0.374618	100.0	0.175

Field	Contents
MID	Material ID of the associated MAT1. See comment 1. No default (Integer > 0)
A	Plasticity yield stress. (Real > 0)
B	Plasticity hardening parameter. (Real > 0)
N	Plasticity hardening exponent. Default = 1.0 (Real < 1.0)
EPSMAX	Failure plastic strain εmax Default = 1030 (Real > 0)
SIGMAX	Maximum plastic stress σmax0 Default = 1030 (Real > 0)
C	Strain rate coefficient. If zero, there is no strain rate effect. Default = 0.0 (Real)
DEPS0	Reference strain rate . Default = 0.0 (Real) If DESPS < DESPS0, no strain rate effect.
ICC	Strain rate dependency of σmax flag. See comment 5. Default = ON (ON or OFF)
FSMOOTH	Strain rate smoothing flag. Default = OFF (ON or OFF)
FCUT	Cutoff frequency for strain rate filtering. Only for shell and solid elements. Default = 1030 (Real > 0)
M	Temperature exponent. Default = 0.0 (Real)
TMELT	Melting temperature. Default = 1030 (Real > 0)
RCP	Specific heat per unit of volume. Default = 0.0 (Real > 0)

Comments

1.	The material identification number must be that of an existing MAT1 bulk data entry. Only one MATXi material extension can be associated with a particular MAT1.

2.	MATX02 is only applied in geometric nonlinear analysis subcases which are defined by ANALYSIS = EXPDYN. It is ignored for all other subcases.

3.	This is an elastic-plastic law with strain rate and thermal effects. It follows:

matx02_eq1

Where,

matx02_eq2

Where, is the plastic strain, is the strain rate, and T is the temperature (in Kelvin).

4.	If the plastic strain reaches EPSMAX, shell elements are deleted. Solid elements are not deleted, but the deviatoric stress is set to zero.

5.	ICC controls the strain rate effect.

matx02

matx02_eq3

6.	No strain rate effects are considered in rod elements.

7.	Strain rate filtering is used to smooth strain rates. The input FCUT is available only for shell and solid elements.

8.	To take into account the temperature effect, strain rate dependence must be activated. If the temperature exponent M = 0; there is no temperature effect. No temperature effect is considered on rod, bar, and beam elements.

9.	The temperature is computed assuming adiabatic conditions:

matx02_eq4

where, Eint is the internal energy.

If ρCp = 0, the temperature is constant: T = Ti

10.	This card is represented as an extension to a MAT1 material in HyperMesh.