def example3():
# T is in hours, strain in percent, stress in MPa
A = 1.85e-10
n = 2.5
smodel = creep.PowerLawCreep(A, n)
cmodel = creep.J2CreepModel(smodel)
E = 150000.0
nu = 0.3
sY = 200.0
H = E / 50.0
elastic = elasticity.IsotropicLinearElasticModel(E, "youngs", nu,
"poissons")
surface = surfaces.IsoJ2()
iso = hardening.LinearIsotropicHardeningRule(sY, H)
flow = ri_flow.RateIndependentAssociativeFlow(surface, iso)
pmodel = models.SmallStrainRateIndependentPlasticity(elastic, flow)
smax = 250.0
R = -0.5
srate = 1.0 * 3600.0
ncycles = 25
hold = 25
res1 = drivers.stress_cyclic(pmodel, smax, R, srate, ncycles,
hold_time = [0,hold])
model = models.SmallStrainCreepPlasticity(elastic, pmodel, cmodel, verbose = False)
res2 = drivers.stress_cyclic(model, smax, R, srate, ncycles,
hold_time = [0,hold], verbose = False)
plt.plot(res1['strain'], res1['stress'], 'k-')
plt.plot(res2['strain'], res2['stress'], 'r-')
plt.show()
plt.figure()
plt.plot(res['strain'], res['stress'], 'k-')
plt.xlabel("Strain (mm/mm)")
plt.ylabel("Stress (MPa)")
plt.title("Strain-controlled cyclic with follow up")
plt.show()
# Stress controlled-cyclic
smax = 200.0
R = -0.75
erate = 1.0e-4
ncycles = 5
hold_time = [10 * 3600.0, 0]
res = drivers.stress_cyclic(model,
smax,
R,
erate,
ncycles,
hold_time=hold_time)
plt.figure()
plt.plot(res['strain'], res['stress'], 'k-')
plt.xlabel("Strain (mm/mm)")
plt.ylabel("Stress (MPa)")
plt.title("Stress-controlled cyclic")
plt.show()
# Stress relaxation
emax = 0.05
erate = 1.0e-4
hold = 1000.0 * 3600.0
res = drivers.stress_relaxation(model, emax, erate, hold)
plt.figure()
# A strain-controlled cyclic test
res = drivers.strain_cyclic(model, 0.01, -0.25, 1.0e-4, 50)
plt.plot(res['strain'], res['stress'], 'k-')
plt.xlabel("Strain (-/-)")
plt.ylabel("Stress (MPa)")
plt.show()
plt.plot(res['cycles'], res['max'], 'k-')
plt.plot(res['cycles'], res['min'], 'k-')
plt.plot(res['cycles'], res['mean'], 'k-')
plt.xlabel("Cycle")
plt.ylabel("Stress (MPa)")
plt.show()
# A stress-controlled cyclic test
res = drivers.stress_cyclic(model, 525.0, -1.0, 5.0, 50, hold_time=100)
plt.plot(res['strain'], res['stress'], 'k-')
plt.xlabel("Strain (-/-)")
plt.ylabel("Stress (MPa)")
plt.show()
plt.plot(res['cycles'], res['max'], 'k-')
plt.plot(res['cycles'], res['min'], 'k-')
plt.plot(res['cycles'], res['mean'], 'k-')
plt.xlabel("Cycle")
plt.ylabel("Strain (-/-)")
plt.show()
# Stress relaxation test
res = drivers.stress_relaxation(model, 0.02, 1.0e-4, 2000.0)
plt.plot(res['time'], res['stress'], 'k-')
n_interp)
rd_flow = general_flow.TVPFlowRule(elastic_m, visco_flow_m)
rd_model = models.GeneralIntegrator(elastic_m, rd_flow)
ri_flow_m = ri_flow.RateIndependentNonAssociativeHardening(
surface_m, hmodel_ri)
ri_model = models.SmallStrainRateIndependentPlasticity(
elastic_m, ri_flow_m)
model = models.KMRegimeModel(elastic_m, [ri_model, rd_model], [g0], kboltz,
b, eps0)
smax = 400.0
Rs = [-1.0, -0.75, -0.5, -0.25, 0.0]
srate = 1.0e-3
ncycles = 50
for R in Rs:
res = drivers.stress_cyclic(model,
smax,
R,
srate,
ncycles,
T=550 + 273.15)
plt.plot(res['cycles'], res['max'])
#plt.plot(res['strain'], res['stress'])
#plt.show()
plt.legend(map(str, Rs))
plt.show()
K = E / 50.0
emodel = elasticity.IsotropicLinearElasticModel(E, "youngs", nu,
"poissons")
surface = surfaces.IsoKinJ2I1(h, l)
hiso = hardening.LinearIsotropicHardeningRule(sY, -K / 10)
hmodel = hardening.Chaboche(hiso, [K * 3.0 / 2.0],
[hardening.ConstantGamma(0.0)], [0.0], [1.0])
flow = ri_flow.RateIndependentNonAssociativeHardening(surface, hmodel)
#hkin = hardening.LinearKinematicHardeningRule(K)
#hmodel = hardening.CombinedHardeningRule(hiso, hkin)
#flow = ri_flow.RateIndependentAssociativeFlow(surface, hmodel)
model = models.SmallStrainRateIndependentPlasticity(emodel, flow)
smax = 200.0
Rs = [-1.0, -0.75, -0.5, -0.25, 0.0]
srate = 1.0
ncycles = 50
for R in Rs:
res = drivers.stress_cyclic(model, smax, R, srate, ncycles)
plt.plot(res['cycles'], res['max'])
plt.legend(map(str, Rs))
plt.show()
res = drivers.strain_cyclic(model, 0.001, -0.25, 1.0e-4, 50,
verbose = False)
plt.plot(res['strain'], res['stress'], 'k-')
plt.xlabel("Strain (-/-)")
plt.ylabel("Stress (MPa)")
plt.show()
plt.plot(res['cycles'], res['max'], 'k-')
plt.plot(res['cycles'], res['min'], 'k-')
plt.plot(res['cycles'], res['mean'], 'k-')
plt.xlabel("Cycle")
plt.ylabel("Stress (MPa)")
plt.show()
# A stress-controlled cyclic test
res = drivers.stress_cyclic(model, 100.0, -1.0, 5.0, 50,
hold_time = 10, verbose = False)
plt.plot(res['strain'], res['stress'], 'k-')
plt.xlabel("Strain (-/-)")
plt.ylabel("Stress (MPa)")
plt.show()
plt.plot(res['cycles'], res['max'], 'k-')
plt.plot(res['cycles'], res['min'], 'k-')
plt.plot(res['cycles'], res['mean'], 'k-')
plt.xlabel("Cycle")
plt.ylabel("Strain (-/-)")
plt.show()
# Stress relaxation test
res = drivers.stress_relaxation(model, 0.02, 1.0e-4, 2000.0, verbose = False)
