DAMASK_EICMD/src/constitutive_plastic_phenop...

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!--------------------------------------------------------------------------------------------------
!> @author Franz Roters, Max-Planck-Institut für Eisenforschung GmbH
!> @author Philip Eisenlohr, Max-Planck-Institut für Eisenforschung GmbH
!> @author Martin Diehl, Max-Planck-Institut für Eisenforschung GmbH
!> @brief phenomenological crystal plasticity formulation using a powerlaw fitting
!--------------------------------------------------------------------------------------------------
submodule(constitutive) plastic_phenopowerlaw
type :: tParameters
real(pReal) :: &
gdot0_slip, & !< reference shear strain rate for slip
gdot0_twin, & !< reference shear strain rate for twin
n_slip, & !< stress exponent for slip
n_twin, & !< stress exponent for twin
spr, & !< push-up factor for slip saturation due to twinning
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c_1, &
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c_2, &
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c_3, &
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c_4, &
h0_SlipSlip, & !< reference hardening slip - slip
h0_TwinSlip, & !< reference hardening twin - slip
h0_TwinTwin, & !< reference hardening twin - twin
a_slip, &
aTolResistance, & !< absolute tolerance for integration of xi
aTolShear, & !< absolute tolerance for integration of gamma
aTolTwinfrac !< absolute tolerance for integration of f
real(pReal), allocatable, dimension(:) :: &
xi_slip_0, & !< initial critical shear stress for slip
xi_twin_0, & !< initial critical shear stress for twin
xi_slip_sat, & !< maximum critical shear stress for slip
nonSchmidCoeff, &
H_int, & !< per family hardening activity (optional)
gamma_twin_char !< characteristic shear for twins
real(pReal), allocatable, dimension(:,:) :: &
interaction_SlipSlip, & !< slip resistance from slip activity
interaction_SlipTwin, & !< slip resistance from twin activity
interaction_TwinSlip, & !< twin resistance from slip activity
interaction_TwinTwin !< twin resistance from twin activity
real(pReal), allocatable, dimension(:,:,:) :: &
Schmid_slip, &
Schmid_twin, &
nonSchmid_pos, &
nonSchmid_neg
integer :: &
totalNslip, & !< total number of active slip system
totalNtwin !< total number of active twin systems
integer, allocatable, dimension(:) :: &
Nslip, & !< number of active slip systems for each family
Ntwin !< number of active twin systems for each family
character(len=pStringLen), allocatable, dimension(:) :: &
output
end type tParameters
type :: tPhenopowerlawState
real(pReal), pointer, dimension(:,:) :: &
xi_slip, &
xi_twin, &
gamma_slip, &
gamma_twin
end type tPhenopowerlawState
!--------------------------------------------------------------------------------------------------
! containers for parameters and state
type(tParameters), allocatable, dimension(:) :: param
type(tPhenopowerlawState), allocatable, dimension(:) :: &
dotState, &
state
contains
!--------------------------------------------------------------------------------------------------
!> @brief Perform module initialization.
!> @details reads in material parameters, allocates arrays, and does sanity checks
!--------------------------------------------------------------------------------------------------
module subroutine plastic_phenopowerlaw_init
integer :: &
Ninstance, &
p, i, &
NipcMyPhase, &
sizeState, sizeDotState, &
startIndex, endIndex
character(len=pStringLen) :: &
extmsg = ''
write(6,'(/,a)') ' <<<+- plastic_'//PLASTICITY_PHENOPOWERLAW_label//' init -+>>>'; flush(6)
Ninstance = count(phase_plasticity == PLASTICITY_PHENOPOWERLAW_ID)
if (iand(debug_level(debug_constitutive),debug_levelBasic) /= 0) &
write(6,'(a16,1x,i5,/)') '# instances:',Ninstance
allocate(param(Ninstance))
allocate(state(Ninstance))
allocate(dotState(Ninstance))
do p = 1, size(phase_plasticity)
if (phase_plasticity(p) /= PLASTICITY_PHENOPOWERLAW_ID) cycle
associate(prm => param(phase_plasticityInstance(p)), &
dot => dotState(phase_plasticityInstance(p)), &
stt => state(phase_plasticityInstance(p)), &
config => config_phase(p))
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!--------------------------------------------------------------------------------------------------
! optional parameters that need to be defined
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prm%c_1 = config%getFloat('twin_c',defaultVal=0.0_pReal)
prm%c_2 = config%getFloat('twin_b',defaultVal=1.0_pReal)
prm%c_3 = config%getFloat('twin_e',defaultVal=0.0_pReal)
prm%c_4 = config%getFloat('twin_d',defaultVal=0.0_pReal)
prm%aTolResistance = config%getFloat('atol_resistance',defaultVal=1.0_pReal)
prm%aTolShear = config%getFloat('atol_shear', defaultVal=1.0e-6_pReal)
prm%aTolTwinfrac = config%getFloat('atol_twinfrac', defaultVal=1.0e-6_pReal)
! sanity checks
if (prm%aTolResistance <= 0.0_pReal) extmsg = trim(extmsg)//' aTolresistance'
if (prm%aTolShear <= 0.0_pReal) extmsg = trim(extmsg)//' aTolShear'
if (prm%aTolTwinfrac <= 0.0_pReal) extmsg = trim(extmsg)//' atoltwinfrac'
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!--------------------------------------------------------------------------------------------------
! slip related parameters
prm%Nslip = config%getInts('nslip',defaultVal=emptyIntArray)
prm%totalNslip = sum(prm%Nslip)
slipActive: if (prm%totalNslip > 0) then
prm%Schmid_slip = lattice_SchmidMatrix_slip(prm%Nslip,config%getString('lattice_structure'),&
config%getFloat('c/a',defaultVal=0.0_pReal))
if(trim(config%getString('lattice_structure')) == 'bcc') then
prm%nonSchmidCoeff = config%getFloats('nonschmid_coefficients',&
defaultVal = emptyRealArray)
prm%nonSchmid_pos = lattice_nonSchmidMatrix(prm%Nslip,prm%nonSchmidCoeff,+1)
prm%nonSchmid_neg = lattice_nonSchmidMatrix(prm%Nslip,prm%nonSchmidCoeff,-1)
else
allocate(prm%nonSchmidCoeff(0))
prm%nonSchmid_pos = prm%Schmid_slip
prm%nonSchmid_neg = prm%Schmid_slip
endif
prm%interaction_SlipSlip = lattice_interaction_SlipBySlip(prm%Nslip, &
config%getFloats('interaction_slipslip'), &
config%getString('lattice_structure'))
prm%xi_slip_0 = config%getFloats('tau0_slip', requiredSize=size(prm%Nslip))
prm%xi_slip_sat = config%getFloats('tausat_slip', requiredSize=size(prm%Nslip))
prm%H_int = config%getFloats('h_int', requiredSize=size(prm%Nslip), &
defaultVal=[(0.0_pReal,i=1,size(prm%Nslip))])
prm%gdot0_slip = config%getFloat('gdot0_slip')
prm%n_slip = config%getFloat('n_slip')
prm%a_slip = config%getFloat('a_slip')
prm%h0_SlipSlip = config%getFloat('h0_slipslip')
! expand: family => system
prm%xi_slip_0 = math_expand(prm%xi_slip_0, prm%Nslip)
prm%xi_slip_sat = math_expand(prm%xi_slip_sat,prm%Nslip)
prm%H_int = math_expand(prm%H_int, prm%Nslip)
! sanity checks
if ( prm%gdot0_slip <= 0.0_pReal) extmsg = trim(extmsg)//' gdot0_slip'
if ( prm%a_slip <= 0.0_pReal) extmsg = trim(extmsg)//' a_slip'
if ( prm%n_slip <= 0.0_pReal) extmsg = trim(extmsg)//' n_slip'
if (any(prm%xi_slip_0 <= 0.0_pReal)) extmsg = trim(extmsg)//' xi_slip_0'
if (any(prm%xi_slip_sat <= 0.0_pReal)) extmsg = trim(extmsg)//' xi_slip_sat'
else slipActive
allocate(prm%interaction_SlipSlip(0,0))
allocate(prm%xi_slip_0(0))
endif slipActive
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!--------------------------------------------------------------------------------------------------
! twin related parameters
prm%Ntwin = config%getInts('ntwin', defaultVal=emptyIntArray)
prm%totalNtwin = sum(prm%Ntwin)
twinActive: if (prm%totalNtwin > 0) then
prm%Schmid_twin = lattice_SchmidMatrix_twin(prm%Ntwin,config%getString('lattice_structure'),&
config%getFloat('c/a',defaultVal=0.0_pReal))
prm%interaction_TwinTwin = lattice_interaction_TwinByTwin(prm%Ntwin,&
config%getFloats('interaction_twintwin'), &
config%getString('lattice_structure'))
prm%gamma_twin_char = lattice_characteristicShear_twin(prm%Ntwin,config%getString('lattice_structure'),&
config%getFloat('c/a'))
prm%xi_twin_0 = config%getFloats('tau0_twin',requiredSize=size(prm%Ntwin))
prm%gdot0_twin = config%getFloat('gdot0_twin')
prm%n_twin = config%getFloat('n_twin')
prm%spr = config%getFloat('s_pr')
prm%h0_TwinTwin = config%getFloat('h0_twintwin')
! expand: family => system
prm%xi_twin_0 = math_expand(prm%xi_twin_0, prm%Ntwin)
! sanity checks
if (prm%gdot0_twin <= 0.0_pReal) extmsg = trim(extmsg)//' gdot0_twin'
if (prm%n_twin <= 0.0_pReal) extmsg = trim(extmsg)//' n_twin'
else twinActive
allocate(prm%interaction_TwinTwin(0,0))
allocate(prm%xi_twin_0(0))
allocate(prm%gamma_twin_char(0))
endif twinActive
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!--------------------------------------------------------------------------------------------------
! slip-twin related parameters
slipAndTwinActive: if (prm%totalNslip > 0 .and. prm%totalNtwin > 0) then
prm%h0_TwinSlip = config%getFloat('h0_twinslip')
prm%interaction_SlipTwin = lattice_interaction_SlipByTwin(prm%Nslip,prm%Ntwin,&
config%getFloats('interaction_sliptwin'), &
config%getString('lattice_structure'))
prm%interaction_TwinSlip = lattice_interaction_TwinBySlip(prm%Ntwin,prm%Nslip,&
config%getFloats('interaction_twinslip'), &
config%getString('lattice_structure'))
else slipAndTwinActive
allocate(prm%interaction_SlipTwin(prm%TotalNslip,prm%TotalNtwin)) ! at least one dimension is 0
allocate(prm%interaction_TwinSlip(prm%TotalNtwin,prm%TotalNslip)) ! at least one dimension is 0
prm%h0_TwinSlip = 0.0_pReal
endif slipAndTwinActive
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!--------------------------------------------------------------------------------------------------
! exit if any parameter is out of range
if (extmsg /= '') &
call IO_error(211,ext_msg=trim(extmsg)//'('//PLASTICITY_PHENOPOWERLAW_label//')')
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!--------------------------------------------------------------------------------------------------
! output pararameters
prm%output = config%getStrings('(output)',defaultVal=emptyStringArray)
!--------------------------------------------------------------------------------------------------
! allocate state arrays
NipcMyPhase = count(material_phaseAt == p) * discretization_nIP
sizeDotState = size(['tau_slip ','gamma_slip']) * prm%totalNslip &
+ size(['tau_twin ','gamma_twin']) * prm%totalNtwin
sizeState = sizeDotState
call material_allocatePlasticState(p,NipcMyPhase,sizeState,sizeDotState,0)
!--------------------------------------------------------------------------------------------------
! locally defined state aliases and initialization of state0 and aTolState
startIndex = 1
endIndex = prm%totalNslip
stt%xi_slip => plasticState(p)%state (startIndex:endIndex,:)
stt%xi_slip = spread(prm%xi_slip_0, 2, NipcMyPhase)
dot%xi_slip => plasticState(p)%dotState(startIndex:endIndex,:)
plasticState(p)%aTolState(startIndex:endIndex) = prm%aTolResistance
startIndex = endIndex + 1
endIndex = endIndex + prm%totalNtwin
stt%xi_twin => plasticState(p)%state (startIndex:endIndex,:)
stt%xi_twin = spread(prm%xi_twin_0, 2, NipcMyPhase)
dot%xi_twin => plasticState(p)%dotState(startIndex:endIndex,:)
plasticState(p)%aTolState(startIndex:endIndex) = prm%aTolResistance
startIndex = endIndex + 1
endIndex = endIndex + prm%totalNslip
stt%gamma_slip => plasticState(p)%state (startIndex:endIndex,:)
dot%gamma_slip => plasticState(p)%dotState(startIndex:endIndex,:)
plasticState(p)%aTolState(startIndex:endIndex) = prm%aTolShear
! global alias
plasticState(p)%slipRate => plasticState(p)%dotState(startIndex:endIndex,:)
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startIndex = endIndex + 1
endIndex = endIndex + prm%totalNtwin
stt%gamma_twin => plasticState(p)%state (startIndex:endIndex,:)
dot%gamma_twin => plasticState(p)%dotState(startIndex:endIndex,:)
plasticState(p)%aTolState(startIndex:endIndex) = prm%aTolShear
plasticState(p)%state0 = plasticState(p)%state ! ToDo: this could be done centrally
end associate
enddo
end subroutine plastic_phenopowerlaw_init
!--------------------------------------------------------------------------------------------------
!> @brief Calculate plastic velocity gradient and its tangent.
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!> @details asummes that deformation by dislocation glide affects twinned and untwinned volume
! equally (Taylor assumption). Twinning happens only in untwinned volume
!--------------------------------------------------------------------------------------------------
pure module subroutine plastic_phenopowerlaw_LpAndItsTangent(Lp,dLp_dMp,Mp,instance,of)
real(pReal), dimension(3,3), intent(out) :: &
Lp !< plastic velocity gradient
real(pReal), dimension(3,3,3,3), intent(out) :: &
dLp_dMp !< derivative of Lp with respect to the Mandel stress
real(pReal), dimension(3,3), intent(in) :: &
Mp !< Mandel stress
integer, intent(in) :: &
instance, &
of
integer :: &
i,k,l,m,n
real(pReal), dimension(param(instance)%totalNslip) :: &
gdot_slip_pos,gdot_slip_neg, &
dgdot_dtauslip_pos,dgdot_dtauslip_neg
real(pReal), dimension(param(instance)%totalNtwin) :: &
gdot_twin,dgdot_dtautwin
Lp = 0.0_pReal
dLp_dMp = 0.0_pReal
associate(prm => param(instance))
call kinetics_slip(Mp,instance,of,gdot_slip_pos,gdot_slip_neg,dgdot_dtauslip_pos,dgdot_dtauslip_neg)
slipSystems: do i = 1, prm%totalNslip
Lp = Lp + (gdot_slip_pos(i)+gdot_slip_neg(i))*prm%Schmid_slip(1:3,1:3,i)
forall (k=1:3,l=1:3,m=1:3,n=1:3) &
dLp_dMp(k,l,m,n) = dLp_dMp(k,l,m,n) &
+ dgdot_dtauslip_pos(i) * prm%Schmid_slip(k,l,i) * prm%nonSchmid_pos(m,n,i) &
+ dgdot_dtauslip_neg(i) * prm%Schmid_slip(k,l,i) * prm%nonSchmid_neg(m,n,i)
enddo slipSystems
call kinetics_twin(Mp,instance,of,gdot_twin,dgdot_dtautwin)
twinSystems: do i = 1, prm%totalNtwin
Lp = Lp + gdot_twin(i)*prm%Schmid_twin(1:3,1:3,i)
forall (k=1:3,l=1:3,m=1:3,n=1:3) &
dLp_dMp(k,l,m,n) = dLp_dMp(k,l,m,n) &
+ dgdot_dtautwin(i)*prm%Schmid_twin(k,l,i)*prm%Schmid_twin(m,n,i)
enddo twinSystems
end associate
end subroutine plastic_phenopowerlaw_LpAndItsTangent
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!--------------------------------------------------------------------------------------------------
!> @brief Calculate the rate of change of microstructure.
!--------------------------------------------------------------------------------------------------
module subroutine plastic_phenopowerlaw_dotState(Mp,instance,of)
real(pReal), dimension(3,3), intent(in) :: &
Mp !< Mandel stress
integer, intent(in) :: &
instance, &
of
real(pReal) :: &
c_SlipSlip,c_TwinSlip,c_TwinTwin, &
xi_slip_sat_offset,&
sumGamma,sumF
real(pReal), dimension(param(instance)%totalNslip) :: &
left_SlipSlip,right_SlipSlip, &
gdot_slip_pos,gdot_slip_neg
associate(prm => param(instance), stt => state(instance), dot => dotState(instance))
sumGamma = sum(stt%gamma_slip(:,of))
sumF = sum(stt%gamma_twin(:,of)/prm%gamma_twin_char)
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!--------------------------------------------------------------------------------------------------
! system-independent (nonlinear) prefactors to M_Xx (X influenced by x) matrices
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c_SlipSlip = prm%h0_slipslip * (1.0_pReal + prm%c_1*sumF** prm%c_2)
c_TwinSlip = prm%h0_TwinSlip * sumGamma**prm%c_3
c_TwinTwin = prm%h0_TwinTwin * sumF**prm%c_4
!--------------------------------------------------------------------------------------------------
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! calculate left and right vectors
left_SlipSlip = 1.0_pReal + prm%H_int
xi_slip_sat_offset = prm%spr*sqrt(sumF)
right_SlipSlip = abs(1.0_pReal-stt%xi_slip(:,of) / (prm%xi_slip_sat+xi_slip_sat_offset)) **prm%a_slip &
* sign(1.0_pReal,1.0_pReal-stt%xi_slip(:,of) / (prm%xi_slip_sat+xi_slip_sat_offset))
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!--------------------------------------------------------------------------------------------------
! shear rates
call kinetics_slip(Mp,instance,of,gdot_slip_pos,gdot_slip_neg)
dot%gamma_slip(:,of) = abs(gdot_slip_pos+gdot_slip_neg)
call kinetics_twin(Mp,instance,of,dot%gamma_twin(:,of))
!--------------------------------------------------------------------------------------------------
! hardening
dot%xi_slip(:,of) = c_SlipSlip * left_SlipSlip * &
matmul(prm%interaction_SlipSlip,dot%gamma_slip(:,of)*right_SlipSlip) &
+ matmul(prm%interaction_SlipTwin,dot%gamma_twin(:,of))
dot%xi_twin(:,of) = c_TwinSlip * matmul(prm%interaction_TwinSlip,dot%gamma_slip(:,of)) &
+ c_TwinTwin * matmul(prm%interaction_TwinTwin,dot%gamma_twin(:,of))
end associate
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end subroutine plastic_phenopowerlaw_dotState
!--------------------------------------------------------------------------------------------------
!> @brief Write results to HDF5 output file.
!--------------------------------------------------------------------------------------------------
module subroutine plastic_phenopowerlaw_results(instance,group)
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integer, intent(in) :: instance
character(len=*), intent(in) :: group
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integer :: o
associate(prm => param(instance), stt => state(instance))
outputsLoop: do o = 1,size(prm%output)
select case(trim(prm%output(o)))
case('resistance_slip')
if(prm%totalNslip>0) call results_writeDataset(group,stt%xi_slip, 'xi_sl', &
'resistance against plastic slip','Pa')
case('accumulatedshear_slip')
if(prm%totalNslip>0) call results_writeDataset(group,stt%gamma_slip,'gamma_sl', &
'plastic shear','1')
case('resistance_twin')
if(prm%totalNtwin>0) call results_writeDataset(group,stt%xi_twin, 'xi_tw', &
'resistance against twinning','Pa')
case('accumulatedshear_twin')
if(prm%totalNtwin>0) call results_writeDataset(group,stt%gamma_twin,'gamma_tw', &
'twinning shear','1')
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end select
enddo outputsLoop
end associate
end subroutine plastic_phenopowerlaw_results
!--------------------------------------------------------------------------------------------------
!> @brief Calculate shear rates on slip systems and their derivatives with respect to resolved
! stress.
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!> @details Derivatives are calculated only optionally.
! NOTE: Against the common convention, the result (i.e. intent(out)) variables are the last to
! have the optional arguments at the end.
!--------------------------------------------------------------------------------------------------
pure subroutine kinetics_slip(Mp,instance,of, &
gdot_slip_pos,gdot_slip_neg,dgdot_dtau_slip_pos,dgdot_dtau_slip_neg)
real(pReal), dimension(3,3), intent(in) :: &
Mp !< Mandel stress
integer, intent(in) :: &
instance, &
of
real(pReal), intent(out), dimension(param(instance)%totalNslip) :: &
gdot_slip_pos, &
gdot_slip_neg
real(pReal), intent(out), optional, dimension(param(instance)%totalNslip) :: &
dgdot_dtau_slip_pos, &
dgdot_dtau_slip_neg
real(pReal), dimension(param(instance)%totalNslip) :: &
tau_slip_pos, &
tau_slip_neg
integer :: i
logical :: nonSchmidActive
associate(prm => param(instance), stt => state(instance))
nonSchmidActive = size(prm%nonSchmidCoeff) > 0
do i = 1, prm%totalNslip
tau_slip_pos(i) = math_mul33xx33(Mp,prm%nonSchmid_pos(1:3,1:3,i))
tau_slip_neg(i) = merge(math_mul33xx33(Mp,prm%nonSchmid_neg(1:3,1:3,i)), &
0.0_pReal, nonSchmidActive)
enddo
where(dNeq0(tau_slip_pos))
gdot_slip_pos = prm%gdot0_slip * merge(0.5_pReal,1.0_pReal, nonSchmidActive) & ! 1/2 if non-Schmid active
* sign(abs(tau_slip_pos/stt%xi_slip(:,of))**prm%n_slip, tau_slip_pos)
else where
gdot_slip_pos = 0.0_pReal
end where
where(dNeq0(tau_slip_neg))
gdot_slip_neg = prm%gdot0_slip * 0.5_pReal & ! only used if non-Schmid active, always 1/2
* sign(abs(tau_slip_neg/stt%xi_slip(:,of))**prm%n_slip, tau_slip_neg)
else where
gdot_slip_neg = 0.0_pReal
end where
if (present(dgdot_dtau_slip_pos)) then
where(dNeq0(gdot_slip_pos))
dgdot_dtau_slip_pos = gdot_slip_pos*prm%n_slip/tau_slip_pos
else where
dgdot_dtau_slip_pos = 0.0_pReal
end where
endif
if (present(dgdot_dtau_slip_neg)) then
where(dNeq0(gdot_slip_neg))
dgdot_dtau_slip_neg = gdot_slip_neg*prm%n_slip/tau_slip_neg
else where
dgdot_dtau_slip_neg = 0.0_pReal
end where
endif
end associate
end subroutine kinetics_slip
!--------------------------------------------------------------------------------------------------
!> @brief Calculate shear rates on twin systems and their derivatives with respect to resolved
! stress. Twinning is assumed to take place only in untwinned volume.
!> @details Derivatives are calculated only optionally.
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! NOTE: Against the common convention, the result (i.e. intent(out)) variables are the last to
! have the optional arguments at the end.
!--------------------------------------------------------------------------------------------------
pure subroutine kinetics_twin(Mp,instance,of,&
gdot_twin,dgdot_dtau_twin)
real(pReal), dimension(3,3), intent(in) :: &
Mp !< Mandel stress
integer, intent(in) :: &
instance, &
of
real(pReal), dimension(param(instance)%totalNtwin), intent(out) :: &
gdot_twin
real(pReal), dimension(param(instance)%totalNtwin), intent(out), optional :: &
dgdot_dtau_twin
real(pReal), dimension(param(instance)%totalNtwin) :: &
tau_twin
integer :: i
associate(prm => param(instance), stt => state(instance))
do i = 1, prm%totalNtwin
tau_twin(i) = math_mul33xx33(Mp,prm%Schmid_twin(1:3,1:3,i))
enddo
where(tau_twin > 0.0_pReal)
gdot_twin = (1.0_pReal-sum(stt%gamma_twin(:,of)/prm%gamma_twin_char)) & ! only twin in untwinned volume fraction
* prm%gdot0_twin*(abs(tau_twin)/stt%xi_twin(:,of))**prm%n_twin
else where
gdot_twin = 0.0_pReal
end where
if (present(dgdot_dtau_twin)) then
where(dNeq0(gdot_twin))
dgdot_dtau_twin = gdot_twin*prm%n_twin/tau_twin
else where
dgdot_dtau_twin = 0.0_pReal
end where
endif
end associate
end subroutine kinetics_twin
end submodule plastic_phenopowerlaw