A local extrapolation based calculation reduction method for the application of constitutive material models for creep fatigue assessment

Isothermal and thermo-mechanical fatigue behavior of the nickel base superalloy Waspaloy™ under uniaxial and biaxial-planar loading

“…8, and the resulting higher damage. This finding are confirmed by the studies of Cui et al [62] and Wang et al [63,64]. Wang et al have done a damage simulation based on a Chaboche model and have proven that the maximum damage is oriented 45°to the loading axes.…”

“…As preferred location for crack initiation the transition area to the edge which was determined by damage simulations [63,64] and metallographic examinations [62]. Because of the different inductor design in our study compared to Cui et al [62] and Wang et al [63,64] the crack initiation was almost located within the gauge area and rarely in the transition radius. One example for the crack initiation within the transition area was the isothermal fatigue test at 923 K with a strain ratio of 0.6%, see Fig.…”

The influence of temperature transients on the lifetime of modern high-chromium rotor steel under service-type loading

“…It is observed that most damaged areas are located in the transition zone characterized by a transition radius, and the cracks run along a direction which is at 451 to both axes. This effect is caused by local stresses, especially shear stresses, and corresponding damage (see [12]). A systematic study of crack distribution is demonstrated in [13].…”

“…With the requirements of frequent start-up und shut-down processes of power plants due to the flexibility of electrical power demand, in addition to creep and creep fatigue endurance, thermal mechanical fatigue cracking behavior has increasingly become an area of great interest (e.g. [6][7][8][9][10][11][12][13][14]). These investigations usually describe TMF life behavior independently of microstructural damage mechanisms.…”

Simulation of creep and cyclic viscoplastic strains in high-Cr steel components based on a modified Becker–Hackenberg model

“…In Hyde's group [24,10], the type-IV cracking in P91 and P92 weldments are studied by using both a Kachanov-type creep law and a Liu-Murakamitype creep law. Scholz and his coworkers [25,26] introduced a damage variable into the constitutive model of cyclic viscoplasticity, which was further decomposed into fatigue damage and creep damage. The Hooke law, the von Mises equivalent stress, and the kinematic and isotropic hardening rules are modified accordingly.…”