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 set of smooth test specimens loaded uniaxially in the [001], [011] and directions at 500 °C with Rε=−1. The numerical procedure is then applied to a series of experiments, in which notched single-crystal test specimens were exposed to uniaxial cyclic loading in the [001] direction at 500 °C with Rε=0.

Nyckelord

Fatigue initiation; Low cycle fatigue; Critical plane approach; Single-crystal superalloy

TECHNOLOGY

TEKNIKVETENSKAP

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)