Role of tangential force coefficient on fretting fatigue life estimation of a single crystal Ni-base superalloy

Abstract

Fretting fatigue behavior of Ni-base superalloys used in gas turbine blades and disk assemblies have been investigated under ambient and high temperature conditions. A major emphasis was placed on the influence of experimentally measured tangential force coefficient on the fretting fatigue life prediction of a single crystal superalloy. Significant differences in the experimental fretting fatigue lives with respect to contacting superalloy combinations were found. These experimental findings were correlated with an analytical approach for the estimation of fretting fatigue life. The predicted results employing the crack analogue model provided good agreement with the experimental results. Also, the influence of secondary crystal orientation of single crystal superalloy on the frictional response and fretting fatigue life prediction was highlighted.

Keywords

• fretting fatigue
• superalloys
• anisotropic
• fatigue life prediction
• crack analogue model