A Mathematical Framework for Cyclic Life Prediction of Directionally Solidified Nickel Superalloys
|Periodical||Advanced Materials Research (Volume 278)|
|Main Theme||Euro Superalloys 2010|
|Edited by||M. Heilmaier|
|Citation||Roland Mücke, 2011, Advanced Materials Research, 278, 363|
|Online since||July, 2011|
|Keywords||Anisotropy, Directionally Solidified, Fatigue, Lifetime Prediction, Superalloy|
Modern gas turbines utilize single crystal (SX) and directionally solidified (DS) nickel superalloys which hold a higher cyclic life resistance and an improved creep rupture strength compared to their conventionally cast (CC) version. Both, SX and DS materials feature a significant direction dependence of material properties, which needs to be considered in the constitutive and lifing models. In this context, the paper presents a mathematical framework of cyclic life prediction. Although the method is developed for DS nickel alloys with transverse isotropic material behaviour, a generalisation to common orthotropic materials inclu¬ding SX is straightforward. The proposed procedure is validated by two examples. Moreover, an application to turbine components is shown.