Evaluation of Fatigue Crack Initiation in a Notched Single-crystal Superalloy Component

• The fatigue crack initiation in a notched single-crystal nickel-base superalloy component at 500 °C was investigated and analysed. A critical plane approach in combination with a critical distance method has been adopted, in which the total shear strain ranges on the discrete slip planes are evaluated. Furthermore, a Coffin-Manson type of expression is used to predict the number of cycles to fatigue crack initiation. The experimental test specimens were studied by microscopy to determine on which crystallographic plane the fatigue initiation occurred. A good correlation between the experimental results and the simulated results were found.

Keyword

single-crystal superalloy

fatigue crack initiation

critical plane approach

notch correction

critical distance theory

TECHNOLOGY

TEKNIKVETENSKAP

Publication and Content Type

ref (subject category)

art (subject category)