fe-safe/TURBOlife™ capabilites

calculations are performed for a single assessment point on a component or for the whole model

for a range of temperatures: Young’s modulus, Poisson’s ratio, monotonic stress-strain curve and cyclic stress-strain curve
the damage required to progress fully from the monotonic stress-strain curve to the cyclic stress-strain curve is specified as a percentage of damage
for a range of temperatures: creep deformation behaviour in terms of creep strain, time and temperature
for a range of temperatures: the fatigue endurance in terms of strain-life
for a range of temperatures: creep rupture ductility versus creep strain rate including the two values of the upper and lower creep ductility plateaus
the creep-fatigue damage envelope in terms of the creep damage: fatigue damage coordinates which define the onset of cracking

Young’s modulus, Poisson’s ratio, monotonic stress-strain curve, cyclic stress-strain curve and creep ductility are linearly interpolated between data sets supplied at different temperatures to obtain the data for the assessment temperature
creep data is enhanced to cover the problem range using the Larson-Miller parameter for interpolation and logarithmic extrapolation

the monotonic and cyclic stress-plastic strain data are fitted to equations of the Ramberg-Osgood form and these equations are used for plasticity calculations
plastic relaxation rules (Neuber, Glinka or –E’) are employed to estimate the actual stress and strain from the elastic stress and strain

the creep deformation data is fitted to polynomial equations and these equations used for the creep calculations
forward creep, creep relaxation or any creep behaviour between these two extremes is accommodated through the use of the elastic follow-up factor Z, the value of which is specified by the user
the creep strain and creep strain rate for all time increments are calculated by the software

from the elastic stress history and the nominated plastic relaxation rule, the elastic-plastic stress history is derived
creep strain effects are added to the elastic-plastic stress history to produce the stress and total strain histories
the individual stress-strain hysteresis loops are identified as fatigue cycles
complete cycles and unmatched half cycles are individually identified
cycle identification is performed as the stress and total strain histories are derived. No post processing of the histories is required

the fatigue damage is calculated for each individual cycle on the basis of the total strain range for that cycle
fatigue damage for unmatched half cycles is calculated as half the damage of the equivalent complete cycle
the creep ductility data is fitted to polynomial equations- these equations are used in the creep damage calculations
creep damage for each time increment is calculated as the creep strain increment divided by the creep ductility as a function of creep strain rate

extensive materials data base covering ferritic steels, stainless steels, chromium steels, nickel based alloys, aluminum alloys, cast iron
materials testing facility from cryogenic temperatures to elevated temperatures including creep
component testing facility for mechanical and thermo-mechanical test cycles
corrosion testing facility
advice on creep and creep fatigue design covering endurance and material selection issues
advice on corrosion and environmental issues
advice on fracture mechanics and the consequences of cracking

fe-safe/TURBOlifeTM also includes all the standard fe-safeTM features for conventional fatigue analysis, including:

fatigue lives at each node or element (3D contour plot)
stress safety factor at each node or element to achieve the design life (3D contour plot)
probability of failure or survival at specified lives (3D contour plot)
load sensitivity shows the effect of each load history on the total fatigue damage
stress histories, cycle histograms, biaxiality, critical plane orientation, Haigh diagrams, fatigue reliability factors, etc, for the whole model or selected elements
a list of the most damaged elements is saved - re-analysis can concentrate on these elements if required
a text file of user inputs, analysis type and a results summary is produced for QA trace-back

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