MATX25

Bulk Data Entry Defines an elasto-plastic orthotropic material with Tsai-Wu and CRASURVT yield criteria for composite shell materials.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
MATX25 MID EPSF1 EPSF2 EPST1 EPSM1 EPST2 EPSM2 DTENDS  
  WPMAX WPREF IOFF GAMINI GAMMAX DMAX RATIO    
  FSMOOTH FCUT IFORM            
Continuation line for IFORM = TSAI
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
  B N FMAX            
  SY1T SY2T SY1C SY2C ALFA        
  SY12C SY12T C12 EPSR0 ICC        
Continuation line for IFORM = CRAS
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
  C EPSR0 ALFA ICCG          
  SY1T B1T N1T SMAX1T C1T        
  EPS1T1 EPS2T1 SRST1 WMPT1          
  SY2T B2T N2T SMAX2T C2T        
  EPS1T2 EPS2T2 SRST2 WMPT2          
  SY1C B1C N1C SMAX1C C1C        
  EPS1C1 EPS2C1 SRSC1 WMPC1          
  SY2C B2C N2C SMAX2C C2C        
  EPS1C2 EPS2C2 SRSC2 WMPC2          
  SY12T B12T N12T SMAX12T C12T        
  EPS1T12 EPS2T12 SRST12 WMPT12          

Example

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
MAT8 102 70000 70000 0.3 26923.1 26923.1 26923.1    
MATX25 102     0.15 0.2     0.95  
      2            
                   
  0.2 1.0 2.0            
  1E10 1E10 1E10 1E10          
  1E10 1E10              

Definitions

Field Contents SI Unit Example
MID Material ID of the associated MAT8. 1

No default (Integer > 0)

 
EPSF1 Total tensile failure in direction 1.

Default = 1E30 (Real)

 
EPSF2 Total tensile failure in direction 2.

Default = 1E30 (Real)

 
EPST1 Tensile failure strain in direction 1.

(Real)

 
EPSM1 Maximum strain in direction 1.

(Real)

 
EPST2 Tensile failure strain in direction 2.

(Real)

 
EPSM2 Maximum strain in direction 2.

(Real)

 
DTENDS Maximum damage of composite tensile strength.

Default = 0.999 (Real < 1.0)

 
WPMAX Maximum plastic work.

Default = 1E30 (Real)

 
WPREF Reference plastic work.

Default = 1.0 (Real)

 
IOFF Total element failure criteria.
=0
Shell is deleted if Wp* > Wp*max for 1 layer
=1
Shell is deleted if Wp* > Wp*max for all layers
=2
If for each layer, Wp* > Wp*max or tensile failure in direction 1(t1)
=3
If for each layer, Wp* > Wp*max or tensile failure in direction 2(t2)
=4
If for each layer, Wp* > Wp*max or tensile failure in directions 1(t1) and 2(t2)
=5
If for all layers: Wp* > Wp*max or tensile failure in direction 1(t1) or if for all layers: Wp* > Wp*max or tensile failure in direction 2(t2)
=6
If for each layer, Wp* > Wp*max or tensile failure in direction 1(t1) or 2(t2)

Default = 0 (Integer)

 
GAMINI Delamination shear strain. 11

Default = 1E30 (Real)

 
GAMMAX Maximum shear strain.

Default = 1.1E30 (Real)

 
DMAX Maximum damage.

Default = 1.0 (Real)

 
RATIO Ratio parameter control to delete shell elements.
< 0.0
The element will be deleted if all of the layers but one fail (the number of layers that did not fail is equal to 1).
> 0.0
The element will be deleted if: number of failed layers number of total layers ratio

Default = 1.0 (Real)

 
FSMOOTH Strain rate smoothing flag.
OFF (Default)
ON
 
FCUT Cutoff frequency for strain rate filtering.

Default = 1E30 (Real)

 
IFORM Formulation flag.
TSAI (Default)
CRAS
 
IFORM=TSAI
B Hardening parameter.

(Real)

 
N Hardening exponent.

Default = 1.0 (Real)

 
FMAX Maximum value of yield function.

Default = 1E30 (Real)

 
SY1T Tension in direction 1.

(Real > 0)

 
SY2T Tension in direction 2.

(Real > 0)

 
SY1C Compression yield stress in direction 1.

(Real > 0)

 
SY2C Compression yield stress in direction 2.

(Real > 0)

 
ALFA F12 reduction factor.

Default = 1.0 (Real)

 
SY12C Compression yield stress in direction 12.

(Real > 0)

 
SY12T Tension yield stress in direction 12.

(Real > 0)

 
C12 Strain rate coefficient.
=0.0
No strain rate dependency.

(Real)

 
EPSR0 Reference strain rate.

(Real)

 
ICC Yield stress in shear and strain rate flag. 9
=0
Default, set to 1
=1
Strain rate effect on FMAX no effect on WPMAX
=2
No strain rate effect on FMAX and WPMAX
=3
Strain rate effect on FMAX and WPMAX
=4
No strain rate effect on FMAX effect on WPMAX

(Integer)

 
IFORM=CRAS
C Global strain rate coefficient for plastic work criteria.

(Real)

 
EPSR0 Reference strain rate.

(Real)

 
ALFA F12 reduction factor.

Default= 1.0 (Real)

 
ICCG Global composite plasticity parameters flag for strain rate computation: 9
=1 (Default)
Strain rate effect on SMAX1T, SMAX2T, SMAX1C, SMAX2C, SMAX12T; no strain rate effect on WPMAX.
=2
No strain rate effect on SMAX1T, SMAX2T, SMAX1C, SMAX2C, SMAX12T; no strain rate effect on WPMAX.
=3
Strain rate effect on SMAX1T, SMAX2T, SMAX1C, SMAX2C, SMAX12T and strain rate effect on WPMAX.
=4
No strain rate effect on SMAX1T, SMAX2T, SMAX1C, SMAX2C, SMAX12T and strain rate effect on WPMAX.

(Integer)

 
SY1T Tension yield stress in direction 1.

(Real > 0)

 
B1T Hardening parameter in direction 1.

(Real)

 
N1T Hardening exponent in direction 1.

Default = 1.0 (Real)

 
SMAX1T Maximum stress in direction 1.

Default = 1E30 (Real)

 
C1T Strain rate coefficient in direction 1.
=0
No strain rate dependency.

Default = C (Real)

 
EPS1T1 Initial softening strain in direction 1.

Default = 1E30 (Real)

 
EPS2T1 Maximum softening strain in direction 1.

Default = 1.2 * EPS1T1 (Real)

 
SRST1 Residual stress in direction 1.

Default = 10E-3*SY1T (Real)

 
WMPT1 Maximum plastic work in tension direction 1.

Default = 1E30 (Real)

 
SY2T Tension yield stress in direction 2.

(Real > 0)

 
B2T Hardening parameter in direction 2.

Default = B1T (Real)

 
N2T Hardening exponent in direction 2.

Default = N1T (Real)

 
SMAX2T Maximum stress in direction 2.

Default = 1E30 (Real)

 
C2T Strain rate coefficient in direction 2.
=0
No strain rate dependency.

Default = C (Real)

 
EPS1T2 Initial softening strain in direction 2.

Default = 1E30 (Real)

 
EPS2T2 Maximum softening strain in direction 2.

Default = 1.2*EPS1T1 (Real)

 
SRST2 Residual stress in direction 2.

Default = 10E-3 * SY2T (Real)

 
WMPT2 Maximum plastic work in tension direction 2.

Default = 1E30 (Real)

 
SY1C Compression yield stress in direction 1.

(Real > 0)

 
B1C Hardening parameter in direction 1.

Default = B2T (Real)

 
N1C Hardening exponent in direction 1.

Default = N2T (Real)

 
SMAX1C Maximum stress in direction 1.

Default = 1E30 (Real)

 
C1C Strain rate coefficient in direction 1.
=0.0
No strain rate dependency.

Default = C (Real)

 
EPS1C1 Initial softening strain in direction 1.

Default = 1E30 (Real)

 
ESP2C1 Maximum softening strain in direction 1.

Default = 1.2*EPS1C1 (Real)

 
SRSC1 Residual stress in direction 1.

Default = 10E-3*S1YC (Real)

 
WMPC1 Maximum plastic work in compression direction 1.

Default = 1E30 (Real)

 
SY2C Compression yield stress in direction 2.

(Real > 0)

 
B2C Hardening parameter in direction 2.

Default = B1C (Real)

 
N2C Hardening exponent in direction 2

Default = N1C (Real)

 
SMAX2C Maximum stress in direction 2.

Default = 1E30 (Real)

 
C2C Strain rate coefficient in direction 2.
=0.0
No strain rate dependency.

Default = C (Real)

 
EPS1C2 Initial softening strain in direction 2.

Default = 1E30 (Real)

 
EPS2C2 Maximum softening strain in direction 2.

Default = 1.2*EPS1C2 (Real)

 
SRSC2 Residual stress in direction 2.

Default = 10E-3*S2YC (Real)

 
WMPC2 Maximum plastic work in compression direction 2.

Default = 1E30 (Real)

 
SY12T Tension yield stress in direction 12.

(Real > 0)

 
B12T Hardening parameter in direction 12.

Default = B2C (Real)

 
N12T Hardening exponent in direction 12.

Default = 1.0 (Real)

 
SMAX12T Maximum stress in direction 12.

Default = 1E30 (Real)

 
C12T Strain rate coefficient in direction 12.
=0.0
No strain rate dependency.

Default = C (Real)

 
EPS1T12 Initial softening strain in direction 12.

Default = 1E30 (Real)

 
EPS2T12 Maximum softening strain in direction 12.

Default = 1.2*EPS1T12 (Real)

 
SRST12 Residual stress in direction 12.

Default = 10E-3*SY12T (Real)

 
WMPT12 Maximum plastic work in shear.

Default = 1E30 (Real)

 

Comments

  1. The material identification number must be that of an existing MAT8 Bulk Data Entry. Only one MATXi material extension can be associated with a particular MAT8.
  2. MATX25 is only applied in geometric nonlinear analysis subcases which are defined by ANALYSIS=EXPDYN. It is ignored for all other subcases.
  3. Tsai-Wu formula (IFORM=TSAI) is not available with QEPH (ISHELL=24 on PCOMPX) shell elements, it is only available with Q4 (ISHELL=1, 2, 3, 4 on PCOMPX) and QBAT(ISHELL=12 on PCOMPX) shell elements.
  4. The Lamina yield surface for Tsai-Wu criteria (IFORM=TSAI) is:(1)
    F = F 1 σ 1 + F 2 σ 2 + F 11 σ 1 2 + F 22 σ 2 2 + F 44 σ 12 2 + 2 F 12 σ 1 σ 2 F ( W p W ref p )
    Where,
    Wp
    Plastic work
    W ref p
    Reference plastic work
    F ( W p W ref p )
    Yield envelope evolution
    Where,
    b
    hardening parameter for plastic work
    n
    hardening exponent
    F 1 = 1 σ 1 y c + 1 σ 1 y t ; F 2 = 1 σ 2 y c + 1 σ 2 y t F 11 = 1 σ 1 y c σ 1 y t ; F 22 = 1 σ 2 y c σ 2 y t F 44 = 1 σ 12 y 2 σ 12 y t ; F 12 = α 2 F 11 F 22
  5. The CRASURV model is an improved version of the former law based on the standard Tsai-Wu criteria. The main changes concern the expression of the yield surface before plastification and during work hardening. First, in a CRASURV model, the coefficient F 44 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8srps0lbbf9q8WrFfeuY=Hhbbf9v8 qqaqFr0xc9pk0xbba9q8WqFfea0=yr0RYxir=Jbba9q8aq0=yq=He9 q8qqQ8frFve9Fve9Ff0dmeaacaGacmGadaWaaiqacaabaiaafaaake aacaWGgbWaaSbaaSqaaiaaisdacaaI0aaabeaaaaa@3B4A@ depends only on one input parameter:(2)
    F 44 = 1 ( σ 12 y ) 2
    Another modification concerns the parameters Fij which are expressed now in function of plastic work and plastic work rate:(3)
    F 1 ( W p ) σ 1 + F 2 ( W p ) σ 2 + F 11 ( W p ) σ 1 2 + F 22 ( W p ) σ 2 2 + F 44 ( W p ) σ 12 2 + 2 F 12 ( W p ) σ 1 σ 2 ( 1 + b W p n ) ( 1 + c ln ε ˙ ε ˙ 0 ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVCI8FfYJH8YrFfeuY=Hhbbf9v8qqaqFr0xc9pk0xbb a9q8WqFfeaY=biLkVcLq=JHqpepeea0=as0Fb9pgeaYRXxe9vr0=vr 0=vqpWqaaeaabiGaciaacaqabeaadaqaaqaaaOabaeqabaaeaaaaaa aaa8qacaWGgbWdamaaBaaaleaapeGaaGymaaWdaeqaaOWdbiaacIca caWGxbWdamaaBaaaleaapeGaamiCaaWdaeqaaOWdbiaacMcacqaHdp WCpaWaaSbaaSqaa8qacaaIXaaapaqabaGcpeGaey4kaSIaamOra8aa daWgaaWcbaWdbiaaikdaa8aabeaak8qacaGGOaGaam4va8aadaWgaa WcbaWdbiaadchaa8aabeaak8qacaGGPaGaeq4Wdm3damaaBaaaleaa peGaaGOmaaWdaeqaaOWdbiabgUcaRiaadAeapaWaaSbaaSqaa8qaca aIXaGaaGymaaWdaeqaaOWdbiaacIcacaWGxbWdamaaBaaaleaapeGa amiCaaWdaeqaaOWdbiaacMcacqaHdpWCpaWaa0baaSqaa8qacaaIXa aapaqaa8qacaaIYaaaaOGaey4kaSIaamOra8aadaWgaaWcbaWdbiaa ikdacaaIYaaapaqabaGcpeGaaiikaiaadEfapaWaaSbaaSqaa8qaca WGWbaapaqabaGcpeGaaiykaiabeo8aZ9aadaqhaaWcbaWdbiaaikda a8aabaWdbiaaikdaaaaak8aabaGaaGzbV=qacqGHRaWkcaWGgbWdam aaBaaaleaapeGaaGinaiaaisdaa8aabeaak8qacaGGOaGaam4va8aa daWgaaWcbaWdbiaadchaa8aabeaak8qacaGGPaGaeq4Wdm3damaaDa aaleaapeGaaGymaiaaikdaa8aabaWdbiaaikdaaaGccqGHRaWkcaaI YaGaamOra8aadaWgaaWcbaWdbiaaigdacaaIYaaapaqabaGcpeGaai ikaiaadEfapaWaaSbaaSqaa8qacaWGWbaapaqabaGcpeGaaiykaiab eo8aZ9aadaWgaaWcbaWdbiaaigdaa8aabeaak8qacqaHdpWCpaWaaS baaSqaa8qacaaIYaaapaqabaGcpeGaeyizIm6aaeWaa8aabaWdbiaa igdacqGHRaWkcaWGIbGaam4va8aadaqhaaWcbaWdbiaadchaa8aaba Wdbiaad6gaaaaakiaawIcacaGLPaaadaqadaWdaeaapeGaaGymaiab gUcaRiaadogacaqGSbGaaeOBamaalaaapaqaa8qacuaH1oqzpaGbai aaaeaapeGafqyTdu2dayaacaWaaSbaaSqaa8qacaaIWaaapaqabaaa aaGcpeGaayjkaiaawMcaaaaaaa@8D02@
    (4)
    σ 1 y c ( W p ) = σ 1 y c ( 1 + b 1 c ( W p 1 c ) n ) ( 1 + c 1 c ln ε ˙ ε ˙ 0 )
    (5)
    σ 2 y c ( W p ) = σ 2 y c ( 1 + b 2 c ( W p 2 c ) n ) ( 1 + c 1 c ln ε ˙ ε ˙ 0 )
    (6)
    σ 1 y t ( W p ) = σ 1 y t ( 1 + b 1 t ( W p 1 t ) n ) ( 1 + c 1 t ln ε ˙ ε ˙ 0 )
    (7)
    σ 2 y t ( W p ) = σ 2 y t ( 1 + b 2 t ( W p 2 t ) n ) ( 1 + c 1 t ln ε ˙ ε ˙ 0 )
    σ 12 y ( W p ) = σ 12 y ( 1 + b 12 ( W p 12 ) n ) ( 1 + c 12 ln ε ˙ ε ˙ 0 )
  6. If the total tensile failure value EPSF1 is reached in the direction 1 and respectively ε EPSF2 in the direction 2, the stresses tensor in the layer is permanently reset to 0.
  7. If a shell has several layers with one material per layer (different materials, different IOFF), the IOFF used is the one that is associated to the shell in the shell element definition.
  8. Both Wp* and Wp*max are defined as:(8)
    W p * = W p W ref p and W p * max = W p max W ref p
  9. The plastic work criteria is:(9)
    W p W ref p > W max p W ref p ( 1 + c ln ε ˙ ε ˙ 0 )

    When ICC=2, 3, or 4 for Tsai-Wu formula, when ICCG=3 or 4 for CRASURV formula.

  10. Delamination is a global model:(10)
    σ 31 = G 31 ( 1 d ) γ 31
    (11)
    σ 23 = G 23 ( 1 d ) γ 23
    with d = γ γ ini γ max γ ini γ max γ applies to the all shell and not independently per each layer.
  11. Thereby, the coefficients GAMINI, GAMMAX, and DMAX considered, are the coefficients which are defined in the global material associated to the shell equivalent out-of-plane shear strain.
  12. The IOFF and RATIO field values are utilized only if they are defined in the material assigned to a part, these fields are not considered if they are only defined in material used for a layer in the property entry. This option is not available for solid elements.
  13. This card is represented as extension to a MAT8 material in HyperMesh.