Crystal viscoplasticity model for the creep-fatigue interactions in single-crystal Ni-base superalloy CMSX-8

Fatigue-creep-environment Interactions in a Directionally-solidified Ni-base Superalloy

Directionally-solidified (DS) GTD-111 is a Ni-base superalloy designed to withstand damage occurring in the first and second stage blades of gas-powered turbines. Because of the distinctive microstructure of this material, the manner in which fatiguecreep-environment damage mechanisms interact to initiate cracks is sensitive to grain structure and chemical composition. Along with fatigue cyclin...

Creep and Stress Relaxation Anisotropy of a Single-Crystal Superalloy

In- and Out-of Phase Thermomechanical Fatigue of a Ni-Based Single-Crystal Superalloy

In this study, the difference between in-phase (IP) and out-of-phase (OP) thermomechanical fatigue (TMF) cycling from 100 to 750 ◦C has been investigated for the Ni-based single-crystal superalloy MD2. In addition, two different crystal orientations were studied, the 〈001〉 and 〈011〉 orientations respectively. When comparing IP and OP TMF lives, a strain range dependency is found for the 〈001〉 d...

Fatigue crack initiation in a notched single-crystal superalloy component

In this paper, the fatigue crack initiation in notched single-crystal test specimens of material MD2 is investigated and analysed. A critical plane approach is adopted, in which the total strain ranges on the discrete slip planes are evaluated. Furthermore, a Coffin-Manson type of expression is used to describe the number of cycles to fatigue crack initiation. This relation is determined from a...

Fretting on the cubic face of a single-crystal Ni-base superalloy at room temperature

Fretting experiments were conducted on the (10 0) crystal (cubic) face of a single crystal Ni-base superalloy in two directions, /10 0S and /110S, to study the effect of crystallographic orientation on the fretting response in both partial slip and gross slip regimes. The study involved point contacts using a tungsten carbide (WC) ball with radius 10 mm tested at room temperature. Ball indentat...