477 lines
20 KiB
Fortran
477 lines
20 KiB
Fortran
!--------------------------------------------------------------------------------------------------
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!> @author Philip Eisenlohr, Michigan State University
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!> @author Zhuowen Zhao, Michigan State University
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!> @author Martin Diehl, Max-Planck-Institut für Eisenforschung GmbH
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!> @brief Phenomenological crystal plasticity using a power law formulation for the shear rates
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!! and a Voce-type kinematic hardening rule
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!--------------------------------------------------------------------------------------------------
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submodule(phase:plastic) kinehardening
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type :: tParameters
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real(pReal) :: &
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n = 1.0_pReal, & !< stress exponent for slip
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dot_gamma_0 = 1.0_pReal !< reference shear strain rate for slip
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real(pReal), allocatable, dimension(:) :: &
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h_0_f, & !< initial hardening rate of forward stress for each slip
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h_inf_f, & !< asymptotic hardening rate of forward stress for each slip
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h_0_b, & !< initial hardening rate of back stress for each slip
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h_inf_b, & !< asymptotic hardening rate of back stress for each slip
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xi_inf_f, &
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xi_inf_b
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real(pReal), allocatable, dimension(:,:) :: &
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h_sl_sl !< slip resistance from slip activity
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real(pReal), allocatable, dimension(:,:,:) :: &
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P, &
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P_nS_pos, &
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P_nS_neg
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integer :: &
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sum_N_sl
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logical :: &
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nonSchmidActive = .false.
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character(len=pStringLen), allocatable, dimension(:) :: &
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output
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character(len=:), allocatable, dimension(:) :: &
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systems_sl
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end type tParameters
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type :: tIndexDotState
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integer, dimension(2) :: &
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xi, &
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chi, &
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gamma
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end type tIndexDotState
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type :: tKinehardeningState
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real(pReal), pointer, dimension(:,:) :: &
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xi, & !< resistance against plastic slip
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chi, & !< back stress
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chi_0, & !< back stress at last switch of stress sense
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gamma, & !< accumulated (absolute) shear
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gamma_0, & !< accumulated shear at last switch of stress sense
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sgn_gamma !< sense of acting shear stress (-1 or +1)
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end type tKinehardeningState
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!--------------------------------------------------------------------------------------------------
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! containers for parameters and state
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type(tParameters), allocatable, dimension(:) :: param
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type(tIndexDotState), allocatable, dimension(:) :: indexDotState
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type(tKinehardeningState), allocatable, dimension(:) :: state, deltaState
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contains
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!--------------------------------------------------------------------------------------------------
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!> @brief Perform module initialization.
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!> @details reads in material parameters, allocates arrays, and does sanity checks
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!--------------------------------------------------------------------------------------------------
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module function plastic_kinehardening_init() result(myPlasticity)
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logical, dimension(:), allocatable :: myPlasticity
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integer :: &
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ph, o, &
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Nmembers, &
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sizeState, sizeDeltaState, sizeDotState, &
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startIndex, endIndex
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integer, dimension(:), allocatable :: &
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N_sl
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real(pReal), dimension(:), allocatable :: &
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xi_0, & !< initial resistance against plastic flow
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a !< non-Schmid coefficients
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character(len=pStringLen) :: &
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extmsg = ''
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class(tNode), pointer :: &
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phases, &
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phase, &
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mech, &
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pl
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myPlasticity = plastic_active('kinehardening')
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if(count(myPlasticity) == 0) return
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print'(/,1x,a)', '<<<+- phase:mechanical:plastic:kinehardening init -+>>>'
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print'(/,a,i0)', ' # phases: ',count(myPlasticity); flush(IO_STDOUT)
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print'(/,1x,a)', 'J.A. Wollmershauser et al., International Journal of Fatigue 36:181–193, 2012'
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print'( 1x,a)', 'https://doi.org/10.1016/j.ijfatigue.2011.07.008'
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phases => config_material%get('phase')
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allocate(param(phases%length))
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allocate(indexDotState(phases%length))
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allocate(state(phases%length))
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allocate(deltaState(phases%length))
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do ph = 1, phases%length
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if (.not. myPlasticity(ph)) cycle
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associate(prm => param(ph), stt => state(ph), dlt => deltaState(ph), &
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idx_dot => indexDotState(ph))
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phase => phases%get(ph)
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mech => phase%get('mechanical')
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pl => mech%get('plastic')
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#if defined (__GFORTRAN__)
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prm%output = output_as1dString(pl)
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#else
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prm%output = pl%get_as1dString('output',defaultVal=emptyStringArray)
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#endif
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!--------------------------------------------------------------------------------------------------
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! slip related parameters
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N_sl = pl%get_as1dInt('N_sl',defaultVal=emptyIntArray)
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prm%sum_N_sl = sum(abs(N_sl))
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slipActive: if (prm%sum_N_sl > 0) then
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prm%systems_sl = lattice_labels_slip(N_sl,phase_lattice(ph))
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prm%P = lattice_SchmidMatrix_slip(N_sl,phase_lattice(ph),phase_cOverA(ph))
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if (phase_lattice(ph) == 'cI') then
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a = pl%get_as1dFloat('a_nonSchmid',defaultVal = emptyRealArray)
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if(size(a) > 0) prm%nonSchmidActive = .true.
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prm%P_nS_pos = lattice_nonSchmidMatrix(N_sl,a,+1)
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prm%P_nS_neg = lattice_nonSchmidMatrix(N_sl,a,-1)
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else
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prm%P_nS_pos = prm%P
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prm%P_nS_neg = prm%P
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end if
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prm%h_sl_sl = lattice_interaction_SlipBySlip(N_sl,pl%get_as1dFloat('h_sl-sl'), &
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phase_lattice(ph))
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xi_0 = pl%get_as1dFloat('xi_0', requiredSize=size(N_sl))
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prm%xi_inf_f = pl%get_as1dFloat('xi_inf_f', requiredSize=size(N_sl))
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prm%xi_inf_b = pl%get_as1dFloat('xi_inf_b', requiredSize=size(N_sl))
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prm%h_0_f = pl%get_as1dFloat('h_0_f', requiredSize=size(N_sl))
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prm%h_inf_f = pl%get_as1dFloat('h_inf_f', requiredSize=size(N_sl))
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prm%h_0_b = pl%get_as1dFloat('h_0_b', requiredSize=size(N_sl))
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prm%h_inf_b = pl%get_as1dFloat('h_inf_b', requiredSize=size(N_sl))
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prm%dot_gamma_0 = pl%get_asFloat('dot_gamma_0')
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prm%n = pl%get_asFloat('n')
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! expand: family => system
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xi_0 = math_expand(xi_0, N_sl)
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prm%xi_inf_f = math_expand(prm%xi_inf_f, N_sl)
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prm%xi_inf_b = math_expand(prm%xi_inf_b, N_sl)
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prm%h_0_f = math_expand(prm%h_0_f, N_sl)
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prm%h_inf_f = math_expand(prm%h_inf_f, N_sl)
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prm%h_0_b = math_expand(prm%h_0_b, N_sl)
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prm%h_inf_b = math_expand(prm%h_inf_b, N_sl)
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!--------------------------------------------------------------------------------------------------
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! sanity checks
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if ( prm%dot_gamma_0 <= 0.0_pReal) extmsg = trim(extmsg)//' dot_gamma_0'
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if ( prm%n <= 0.0_pReal) extmsg = trim(extmsg)//' n'
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if (any(xi_0 <= 0.0_pReal)) extmsg = trim(extmsg)//' xi_0'
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if (any(prm%xi_inf_f <= 0.0_pReal)) extmsg = trim(extmsg)//' xi_inf_f'
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if (any(prm%xi_inf_b <= 0.0_pReal)) extmsg = trim(extmsg)//' xi_inf_b'
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else slipActive
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xi_0 = emptyRealArray
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allocate(prm%xi_inf_f,prm%xi_inf_b,prm%h_0_f,prm%h_inf_f,prm%h_0_b,prm%h_inf_b,source=emptyRealArray)
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allocate(prm%h_sl_sl(0,0))
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end if slipActive
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!--------------------------------------------------------------------------------------------------
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! allocate state arrays
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Nmembers = count(material_phaseID == ph)
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sizeDotState = size(['xi ','chi ', 'gamma']) * prm%sum_N_sl
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sizeDeltaState = size(['sgn_gamma', 'chi_0 ', 'gamma_0 ']) * prm%sum_N_sl
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sizeState = sizeDotState + sizeDeltaState
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call phase_allocateState(plasticState(ph),Nmembers,sizeState,sizeDotState,sizeDeltaState)
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deallocate(plasticState(ph)%dotState) ! ToDo: remove dotState completely
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!--------------------------------------------------------------------------------------------------
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! state aliases and initialization
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startIndex = 1
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endIndex = prm%sum_N_sl
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idx_dot%xi = [startIndex,endIndex]
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stt%xi => plasticState(ph)%state(startIndex:endIndex,:)
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stt%xi = spread(xi_0, 2, Nmembers)
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plasticState(ph)%atol(startIndex:endIndex) = pl%get_asFloat('atol_xi',defaultVal=1.0_pReal)
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if(any(plasticState(ph)%atol(startIndex:endIndex) < 0.0_pReal)) extmsg = trim(extmsg)//' atol_xi'
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startIndex = endIndex + 1
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endIndex = endIndex + prm%sum_N_sl
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idx_dot%chi = [startIndex,endIndex]
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stt%chi => plasticState(ph)%state(startIndex:endIndex,:)
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plasticState(ph)%atol(startIndex:endIndex) = pl%get_asFloat('atol_xi',defaultVal=1.0_pReal)
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startIndex = endIndex + 1
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endIndex = endIndex + prm%sum_N_sl
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idx_dot%gamma = [startIndex,endIndex]
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stt%gamma => plasticState(ph)%state(startIndex:endIndex,:)
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plasticState(ph)%atol(startIndex:endIndex) = pl%get_asFloat('atol_gamma',defaultVal=1.0e-6_pReal)
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if(any(plasticState(ph)%atol(startIndex:endIndex) < 0.0_pReal)) extmsg = trim(extmsg)//' atol_gamma'
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o = plasticState(ph)%offsetDeltaState
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startIndex = endIndex + 1
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endIndex = endIndex + prm%sum_N_sl
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stt%sgn_gamma => plasticState(ph)%state (startIndex :endIndex ,:)
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dlt%sgn_gamma => plasticState(ph)%deltaState(startIndex-o:endIndex-o,:)
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startIndex = endIndex + 1
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endIndex = endIndex + prm%sum_N_sl
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stt%chi_0 => plasticState(ph)%state (startIndex :endIndex ,:)
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dlt%chi_0 => plasticState(ph)%deltaState(startIndex-o:endIndex-o,:)
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startIndex = endIndex + 1
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endIndex = endIndex + prm%sum_N_sl
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stt%gamma_0 => plasticState(ph)%state (startIndex :endIndex ,:)
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dlt%gamma_0 => plasticState(ph)%deltaState(startIndex-o:endIndex-o,:)
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end associate
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!--------------------------------------------------------------------------------------------------
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! exit if any parameter is out of range
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if (extmsg /= '') call IO_error(211,ext_msg=trim(extmsg))
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end do
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end function plastic_kinehardening_init
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!--------------------------------------------------------------------------------------------------
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!> @brief Calculate plastic velocity gradient and its tangent.
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!--------------------------------------------------------------------------------------------------
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pure module subroutine kinehardening_LpAndItsTangent(Lp,dLp_dMp,Mp,ph,en)
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real(pReal), dimension(3,3), intent(out) :: &
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Lp !< plastic velocity gradient
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real(pReal), dimension(3,3,3,3), intent(out) :: &
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dLp_dMp !< derivative of Lp with respect to the Mandel stress
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real(pReal), dimension(3,3), intent(in) :: &
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Mp !< Mandel stress
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integer, intent(in) :: &
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ph, &
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en
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integer :: &
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i,k,l,m,n
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real(pReal), dimension(param(ph)%sum_N_sl) :: &
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dot_gamma_pos,dot_gamma_neg, &
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ddot_gamma_dtau_pos,ddot_gamma_dtau_neg
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Lp = 0.0_pReal
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dLp_dMp = 0.0_pReal
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associate(prm => param(ph))
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call kinetics(Mp,ph,en,dot_gamma_pos,dot_gamma_neg,ddot_gamma_dtau_pos,ddot_gamma_dtau_neg)
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do i = 1, prm%sum_N_sl
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Lp = Lp + (dot_gamma_pos(i)+dot_gamma_neg(i))*prm%P(1:3,1:3,i)
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forall (k=1:3,l=1:3,m=1:3,n=1:3) &
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dLp_dMp(k,l,m,n) = dLp_dMp(k,l,m,n) &
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+ ddot_gamma_dtau_pos(i) * prm%P(k,l,i) * prm%P_nS_pos(m,n,i) &
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+ ddot_gamma_dtau_neg(i) * prm%P(k,l,i) * prm%P_nS_neg(m,n,i)
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end do
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end associate
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end subroutine kinehardening_LpAndItsTangent
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!--------------------------------------------------------------------------------------------------
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!> @brief Calculate the rate of change of microstructure.
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!--------------------------------------------------------------------------------------------------
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module function plastic_kinehardening_dotState(Mp,ph,en) result(dotState)
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real(pReal), dimension(3,3), intent(in) :: &
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Mp !< Mandel stress
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integer, intent(in) :: &
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ph, &
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en
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real(pReal), dimension(plasticState(ph)%sizeDotState) :: &
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dotState
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real(pReal) :: &
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sumGamma
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real(pReal), dimension(param(ph)%sum_N_sl) :: &
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dot_gamma_pos,dot_gamma_neg
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associate(prm => param(ph), stt => state(ph), &
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dot_xi => dotState(IndexDotState(ph)%xi(1):IndexDotState(ph)%xi(2)),&
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dot_chi => dotState(IndexDotState(ph)%chi(1):IndexDotState(ph)%chi(2)),&
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dot_gamma => dotState(IndexDotState(ph)%gamma(1):IndexDotState(ph)%gamma(2)))
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call kinetics(Mp,ph,en,dot_gamma_pos,dot_gamma_neg)
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dot_gamma = abs(dot_gamma_pos+dot_gamma_neg)
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sumGamma = sum(stt%gamma(:,en))
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dot_xi = matmul(prm%h_sl_sl,dot_gamma) &
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* ( prm%h_inf_f &
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+ (prm%h_0_f - prm%h_inf_f + prm%h_0_f*prm%h_inf_f*sumGamma/prm%xi_inf_f) &
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* exp(-sumGamma*prm%h_0_f/prm%xi_inf_f) &
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)
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dot_chi = stt%sgn_gamma(:,en)*dot_gamma &
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* ( prm%h_inf_b &
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+ (prm%h_0_b - prm%h_inf_b &
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+ prm%h_0_b*prm%h_inf_b/(prm%xi_inf_b+stt%chi_0(:,en))*(stt%gamma(:,en)-stt%gamma_0(:,en))&
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) *exp(-(stt%gamma(:,en)-stt%gamma_0(:,en)) *prm%h_0_b/(prm%xi_inf_b+stt%chi_0(:,en))) &
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)
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end associate
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end function plastic_kinehardening_dotState
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!--------------------------------------------------------------------------------------------------
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!> @brief Calculate (instantaneous) incremental change of microstructure.
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!--------------------------------------------------------------------------------------------------
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module subroutine plastic_kinehardening_deltaState(Mp,ph,en)
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real(pReal), dimension(3,3), intent(in) :: &
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Mp !< Mandel stress
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integer, intent(in) :: &
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ph, &
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en
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real(pReal), dimension(param(ph)%sum_N_sl) :: &
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dot_gamma_pos,dot_gamma_neg, &
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sgn_gamma
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associate(prm => param(ph), stt => state(ph), dlt => deltaState(ph))
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call kinetics(Mp,ph,en,dot_gamma_pos,dot_gamma_neg)
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sgn_gamma = merge(state(ph)%sgn_gamma(:,en), &
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sign(1.0_pReal,dot_gamma_pos+dot_gamma_neg), &
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dEq0(dot_gamma_pos+dot_gamma_neg,1e-10_pReal))
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where(dNeq(sgn_gamma,stt%sgn_gamma(:,en),0.1_pReal)) ! ToDo sgn_gamma*stt%sgn_gamma(:,en)<0
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dlt%sgn_gamma (:,en) = sgn_gamma - stt%sgn_gamma(:,en)
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dlt%chi_0 (:,en) = abs(stt%chi(:,en)) - stt%chi_0(:,en)
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dlt%gamma_0(:,en) = stt%gamma(:,en) - stt%gamma_0(:,en)
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else where
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dlt%sgn_gamma (:,en) = 0.0_pReal
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dlt%chi_0 (:,en) = 0.0_pReal
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dlt%gamma_0(:,en) = 0.0_pReal
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end where
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end associate
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end subroutine plastic_kinehardening_deltaState
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!--------------------------------------------------------------------------------------------------
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!> @brief Write results to HDF5 output file.
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!--------------------------------------------------------------------------------------------------
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module subroutine plastic_kinehardening_results(ph,group)
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integer, intent(in) :: ph
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character(len=*), intent(in) :: group
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integer :: ou
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associate(prm => param(ph), stt => state(ph))
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do ou = 1,size(prm%output)
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select case(trim(prm%output(ou)))
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case ('xi')
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call results_writeDataset(stt%xi,group,trim(prm%output(ou)), &
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'resistance against plastic slip','Pa',prm%systems_sl)
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case ('chi')
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call results_writeDataset(stt%chi,group,trim(prm%output(ou)), &
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'back stress','Pa',prm%systems_sl)
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case ('sgn(gamma)')
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call results_writeDataset(int(stt%sgn_gamma),group,trim(prm%output(ou)), &
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'sense of shear','1',prm%systems_sl)
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case ('chi_0')
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call results_writeDataset(stt%chi_0,group,trim(prm%output(ou)), &
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'back stress at last switch of stress sense','Pa',prm%systems_sl)
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case ('gamma_0')
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call results_writeDataset(stt%gamma_0,group,trim(prm%output(ou)), &
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'plastic shear at last switch of stress sense','1',prm%systems_sl)
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case ('gamma')
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call results_writeDataset(stt%gamma,group,trim(prm%output(ou)), &
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'plastic shear','1',prm%systems_sl)
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end select
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end do
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end associate
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end subroutine plastic_kinehardening_results
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!--------------------------------------------------------------------------------------------------
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!> @brief Calculate shear rates on slip systems and their derivatives with respect to resolved
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! stress.
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!> @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
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! have the optional arguments at the end.
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!--------------------------------------------------------------------------------------------------
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pure subroutine kinetics(Mp,ph,en, &
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dot_gamma_pos,dot_gamma_neg,ddot_gamma_dtau_pos,ddot_gamma_dtau_neg)
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real(pReal), dimension(3,3), intent(in) :: &
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Mp !< Mandel stress
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integer, intent(in) :: &
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ph, &
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en
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real(pReal), intent(out), dimension(param(ph)%sum_N_sl) :: &
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dot_gamma_pos, &
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dot_gamma_neg
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real(pReal), intent(out), dimension(param(ph)%sum_N_sl), optional :: &
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ddot_gamma_dtau_pos, &
|
||
ddot_gamma_dtau_neg
|
||
|
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real(pReal), dimension(param(ph)%sum_N_sl) :: &
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||
tau_pos, &
|
||
tau_neg
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||
integer :: i
|
||
|
||
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associate(prm => param(ph), stt => state(ph))
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||
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do i = 1, prm%sum_N_sl
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tau_pos(i) = math_tensordot(Mp,prm%P_nS_pos(1:3,1:3,i)) - stt%chi(i,en)
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tau_neg(i) = merge(math_tensordot(Mp,prm%P_nS_neg(1:3,1:3,i)) - stt%chi(i,en), &
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0.0_pReal, prm%nonSchmidActive)
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||
end do
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||
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where(dNeq0(tau_pos))
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dot_gamma_pos = prm%dot_gamma_0 * merge(0.5_pReal,1.0_pReal, prm%nonSchmidActive) & ! 1/2 if non-Schmid active
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* sign(abs(tau_pos/stt%xi(:,en))**prm%n, tau_pos)
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||
else where
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||
dot_gamma_pos = 0.0_pReal
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||
end where
|
||
|
||
where(dNeq0(tau_neg))
|
||
dot_gamma_neg = prm%dot_gamma_0 * 0.5_pReal & ! only used if non-Schmid active, always 1/2
|
||
* sign(abs(tau_neg/stt%xi(:,en))**prm%n, tau_neg)
|
||
else where
|
||
dot_gamma_neg = 0.0_pReal
|
||
end where
|
||
|
||
if (present(ddot_gamma_dtau_pos)) then
|
||
where(dNeq0(dot_gamma_pos))
|
||
ddot_gamma_dtau_pos = dot_gamma_pos*prm%n/tau_pos
|
||
else where
|
||
ddot_gamma_dtau_pos = 0.0_pReal
|
||
end where
|
||
end if
|
||
if (present(ddot_gamma_dtau_neg)) then
|
||
where(dNeq0(dot_gamma_neg))
|
||
ddot_gamma_dtau_neg = dot_gamma_neg*prm%n/tau_neg
|
||
else where
|
||
ddot_gamma_dtau_neg = 0.0_pReal
|
||
end where
|
||
end if
|
||
|
||
end associate
|
||
|
||
end subroutine kinetics
|
||
|
||
end submodule kinehardening
|