1. Reference problem#

1.1. Geometry#

The geometry of the C modeling is that of a 10-grain aggregate generated by a Python procedure based on Voronoi cells. Edge cutting planes are defined to impose boundary conditions.

_images/10000000000004F90000027712DF9B4A647D3410.png

The other models are carried out on hardware points (SIMU_POINT_MAT).

1.2. Material properties#

1.2.1. Modeling B: single crystal#

This modeling makes it possible to validate the single-crystal elasto-visco-plastic model with implicit integration, by comparison with model MONOCRISTAL on a hardware point.

The material coefficients are:

E

208000

NAKED

0.3

G

80000

N

10

K

25

C

14363

R_0

66,62

Q

11,43

B

2,1

D

494

The Mfront files defining the behavior are:

MonoCrystal_ CFC .mfront

1.2.2. C modeling: single crystal on an aggregate of 10 grains#

This modeling makes it possible to validate the single-crystal elasto-visco-plastic model with implicit integration, and complete definition of the family of sliding systems and the interaction matrix, compared to model MONOCRISTAL on a 10-grain aggregate.

The material coefficients are:

E

210000

NAKED

0.3

G

80769.23

N

12

K

5

C

0

R_0

250

Q

55

B

12

D

0

The Mfront files defining the behavior are:

MonoCrystal_ CFC .mfront

1.2.3. Modeling D: polycrystal homogenized on 30 grains#

This modeling makes it possible to validate the polycrystalline elasto-visco-plastic model with explicit integration, by comparison with model POLYCRISTAL on a hardware point with 30 grains. The material coefficients are:

E

145200

NAKED

0.3

G

55846.15

N

10

K

40

C

0

R_0

75.5

Q

9.77

B

19.34

D

0

The Mfront files defining the behavior are:

Polycrystal_mc.mfront

Polycrystal_Orientation.mfront

The « Polycrystal_Orientation.mfront » file defines 30 Euler angle triplets in degrees.

1.2.4. E modeling: single crystal DD_CFC#

This modeling makes it possible to validate the monocrystalline model DD_CFC on a hardware point, in comparison with MONO_DD_CFC. The material coefficients are:

E

208000

NAKED

0.3

G

80000

TAU_F

105

Y

2.5E-7

N

5

GAMMA_0

1.E-3

A

0.13

B

0.005

RHOREF

1.E6

ALPHA

0.35

BETA

2,54E-7

G

80000

The initial dislocation density is 1.E6. The analytical solution is contained in the file mfron03e.30. The Mfront files defining the behavior are:

MonoCrystal DDCFC .mfront

MonoCrystal_ DD_CFC_InteractionMatrix .mfront

1.2.5. F modeling: homogenized polycrystal of type DD_CFC on 30 grains#

This modeling makes it possible to validate the homogenized polycrystalline model DD_CFC on a hardware point with 30 grains, in comparison with POLYCRISTAL. The material coefficients are:

E

208000

NAKED

0.3

G

80000

TAU_F

80

Y

2.5E-7

N

20

GAMMA_0

1.E-3

A

0.13

B

0.005

RHOREF

1.E6

ALPHA

0.35

BETA

2,54E-7

G

80000

The initial dislocation density is 1.E5. The Mfront files defining the behavior are:

PolyCrystal DDCFC .mfront

MonoCrystal_ DD_CFC_InteractionMatrix .mfront

The « Polycrystal_Orientation.mfront » file defines 30 Euler angle triplets in degrees.

1.2.6. G modeling: single crystal DD_CFC_IRRA#

This modeling makes it possible to validate the model DD_CFC_IRRA on a hardware point, in comparison with the behavior MONO_DD_CFC_IRRA. The material coefficients are:

E

208000

NAKED

0.3

G

80000

TAU_F

80

Y

2.5E-7

N

20

GAMMA_0

1.E-3

A

0.13

B

0.005

RHOREF

1.E6

ALPHA

0.35

BETA

2,54E-7

G

80000

ome_void

1000,

PHI_LOOP

5,9E-6

ALP_VOID

0

ALP_LOOP

0,1

ome_sat

0

PHI_SAT

4, E-2

XI_IRRA

10

DZ_IRRA

1, E7

The initial internal variables are:

RHO_0 =1, E5

RHO_LOOPS =7, 4E13

PHI_VOIDS =1.e-3

The Mfront files defining the behavior are:

Mono DDCFC_Irra .mfront

MonoCrystal_ DD_CFC_InteractionMatrix .mfront

1.2.7. H modeling: single crystal DD_CC#

This modeling makes it possible to validate the DD_CCsur model at a hardware point, by comparison with the MONO_DD_CC behavior of the ssnd110b test. The material coefficients are:

E (GPa)

236-0.0459* TEMP

NAKED

0.35

G

80000

B

2,48e-7

GH

1.e11

DeltaG0

0.84

TAU_0 (MPa)

363

TAU_F

0

gamma0

1, e-6

n

50

rho_ini

1, E5*b**2

D

1.e-5

d_lat

y_at

2.e-6

K_f

30,

K_self

100

k_boltz

8.62E-5

epsi_1

3e-4

G

80000

a_self

0.1024

a_coli

0.7

a_ncol

0,1

The simulation temperature is 50 K.

The initial dislocation density is 1.E5 (multiplied by BETA **2).

The Mfront files defining the behavior are:

MonoCrystal DDCC .mfront

MonoCrystal_ DD_CC_InteractionMatrix .mfront

MonoCrystal_ DD_CC_SlidingSystems .mfront

The monocrystal is defined according to the -1,4,9 orientation. It is subject to an imposed deformation \({\epsilon }_{\mathit{zz}}\).

1.2.8. Modeling I: single crystal DD_CC_IRRA#

This modeling makes it possible to validate model DD_CC_IRRA on a hardware point, by comparison with the MONO_DD_CC_IRRA behavior of the ssnd110d test. The material coefficients are:

E (GPa)

236-0.0459* TEMP

NAKED

0.35

G

80000

B

2,48e-7

GH

1.e11

DeltaG0

0.84

TAU_0 (MPa)

363

TAU_F

20

gamma0

1, e-3

n

20

rho_ini

1, E5*b**2

D

1.e-5

d_lat

y_at

1.e-6

K_f

30,

K_self

100

k_boltz

8.62E-5

epsi_1

1e-5

G

80000

a_irr

0.3

xi_irr

4

a_self

0.1024

a_coli

0.7

a_ncol

0,1

The simulation temperature is 250 K.

The monocrystal is subjected to a tensile force imposed according to the orientation 1,5,9

The initial dislocation density is 1.E5 (multiplied by BETA **2). The Mfront files defining the behavior are:

Mono DDCC_Irra .mfront

MonoCrystal_ DD_CC_InteractionMatrix .mfront

MonoCrystal_ DD_CC_SlidingSystems .mfront

1.2.9. K modeling: homogenized polycrystal DD_CC#

This modeling makes it possible to validate the homogenized polycrystalline model DD_CCsur a hardware point with 30 grains, by comparison with the POLYCRISTALdu ssnv194D test behavior. The material coefficients are:

E (GPa)

236-0.0459* TEMP

NAKED

0.35

G

80000

B

2,48e-7

GH

1.e11

DeltaG0

0.84

TAU_0 (MPa)

363

TAU_F

0

gamma0

1, e-6

n

50

rho_ini

1, E5*b**2

D

1.e-5

d_lat

y_at

2.e-6

K_f

30,

K_self

100

k_boltz

8.62E-5

epsi_1

3e-4

G

80000

a_self

0.1024

a_coli

0.7

a_ncol

0,1

The Mfront files defining the behavior are:

PolyCrystal DDCC .mfront

PolyCrystal_ DD_CC_SlidingSystems .mfront

MonoCrystal_ DD_CC_InteractionMatrix .mfront