Damage‐based low‐cycle fatigue lifetime prediction of nickel‐based single‐crystal superalloy considering anisotropy and dwell types

Abstract

Based on the physical phenomenon that the fatigue cracks initiate along specific slip plane, a slip plane damage-based low-cycle fatigue (LCF) lifetime model for the nickel-based single-crystal superalloy is established. The predicted results indicate that the lifetime model can reflect the orientation effect. In addition, in order to characterize the dwell-time dependence of the LCF lifetime, creep damage and compression-creep damage are introduced to the lifetime model. Finally, the lifetime predictions under LCF loading with tensile dwell time, compressive dwell time and tensile-compressive dwell time are conducted by employing the lifetime model, respectively. The predicted lifetimes show a good agreement with the experimental data, which verifies the accuracy of the developed lifetime model in this paper.

A thickness‐sensitive and orientation‐related creep lifetime prediction method of nickel‐based single crystal superalloy

“…In this paper, it is assumed that the damage of zone 1 and zone 2 of the thin‐walled specimen could be described by Equations (2) and (3), while the material constants of zone 1 and zone 2 are different due to the difference of damage mechanisms between surface and interior. According to the crystal plasticity theory, only octahedral slip systems are activated for nickel‐based single crystal superalloys when the uniaxial load is applied along [001] orientation 55 . Assuming that at t = 0 and at t , for nickel‐based single crystal superalloy with [001] orientation, D 1 can be determined by integrating Equation (2): where , , and are the temperature‐dependent material constants of the damage in zone 1.…”

“…According to the crystal plasticity theory, only octahedral slip systems are activated for nickel-based single crystal superalloys when the uniaxial load is applied along [001] orientation. 55 Assuming that D oct c ¼ 0 at t = 0 and D oct c ¼ D 1 at t, for nickel-based single crystal superalloy with [001] orientation, D 1 can be determined by integrating Equation (2):…”

High temperature creep fracture behavior of nickel-base single crystal superalloys

“…Nickel-base single crystal superalloy can maintain high resistance to creep, fatigue, oxidation, and thermal corrosion even under conditions close to 90% of their melting point [1][2][3][4][5]. They also exhibit excellent compositional compatibility and structural stability, making them widely used in the turbine blades of advanced aviation engines.…”

Use of Prandtl operators in simulating the cyclic softening of Inconel 718 under isothermal low-cycle fatigue loading

“…A type of non-linear mechanical behaviour under LCF loading has recently been investigated with increasing efforts [42,43,44,45,46,47,48,49,50,51,52,53,54,55]. Li et al [49] simulated the cyclic softening of 10%Cr martensitic steel via the kinematic hardening rule, by evolving the parameters with an increasing plastic strain.…”