MATX27

Bulk Data Entry Defines additional material properties for elastic-plastic brittle material for geometric nonlinear analysis.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
MATX27 MID A B N EPSMAX SIGMAX C DEPS0  
  ICC                
  EPS1 EPS1MAX D1MAX EPSD1 EPS2 EPS2MAX D2MAX ESPD2  

Example

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
MAT1 127 60.4   0.33 2.70E-06        
MATX27 127 0.09026 0.22313 0.374618 100.0 0.175      

Definitions

Field Contents SI Unit Example
MID Material ID of the associated MAT1. 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 ε max .

Default = 1030 (Real > 0)

 
SIGMAX Maximum plastic stress σ max 0 .

Default = 1030 (Real > 0)

 
C Strain rate coefficient.

Default = 0.0 (Real)

 
DEPS0 Reference strain rate ε ˙ 0 .

Default = 0.0 (Real)

If DESPSDESPS0, no strain rate effect.

 
ICC Strain rate dependency of σ max flag. 4
OFF
ON (Default)
 
EPS1 Tensile failure strain in principal strain direction 1.

Default = 1.0*1030 (Real > 0)

 
EPS1MAX Maximum tensile failure strain in principal strain direction 1.

Default = 1.1*1030 (Real > 0)

 
DMAX1 Maximum tensile failure damage in principal strain direction 1.

Default = 0.999 (Real > 0)

 
EPSD1 Tensile strain for element deletion in principal strain direction 2.

Default = 1.2*1030 (Real > 0)

 
EPS2 Tensile failure strain in principal strain direction 2.

Default = 1.0*1030 (Real > 0)

 
EPS2MAX Maximum tensile failure strain in principal strain direction 2.

Default = 1.1*1030 (Real > 0)

 
DMAX2 Maximum tensile failure damage in principal strain direction 2.

Default = 0.999 (Real > 0)

 
EPSD2 Tensile strain for element deletion in principal strain direction 2.

Default = 1.2*1030 (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. MATX27 is only applied in geometric nonlinear analysis subcases which are defined by ANALYSIS=EXPDYN. It is ignored for all other subcases.
  3. This law is only applicable with shell elements. The isotropic elasto-plastic model is the same as with MATX02. However, MATX27 allows material damage and brittle failure to be modeled.
  4. ICC controls the strain rate effect.


    Figure 1.
    σ = σ y ( 1 + cIn ( ε ˙ ε ˙ 0 ) ) σ max = σ max 0 ( 1 + cIn ε ˙ ε ˙ 0 )
    σ = σ y ( 1 + cIn ( ε ˙ ε ˙ 0 ) ) σ max = σ max 0
  5. The failure plastic strain EPSMAX has no effect if the second continuation is defined.
  6. An element is removed if one layer reaches the tensile failure strain EPS1.


    Figure 2.
  7. This card is represented as an extension to a MAT1 material in HyperMesh.