Journal Published Online: 14 May 2014
Volume 3, Issue 2

Towards the Development of a Physics-Based Thermo-Mechanical Fatigue Life Prediction Model for a Single Crystalline Ni-Base Superalloy

CODEN: MPCACD

Abstract

A long term effort has been underway to develop a mechanism-based model for life prediction under thermo-mechanical fatigue (TMF) cycling. A model has been developed which is based upon the impingement of slip bands upon oxidized regions and subsequent initiation of a crack due to stress concentration. The concept of an effective cycle temperature, T eff, and the dynamic nature of the material are critical components of the model and result in the ability to produce very accurate life predictions. It has also been shown that the model is capable of addressing complexities such as imposed high cycle fatigue (HCF) while still producing excellent agreement with the experiment. However, given the fact that this material is used for jet engine turbine blades and that such blades have cooling holes which act as notches, the next step in the development of this model is to incorporate it into a notched environment. The principal features of the TMF model are reviewed and a strategy for full integration into notched fatigue life prediction is discussed. Recent experimental results are presented which are based upon simulating smooth bar conditions at the notch root and a first approach to numerical simulation (called Q fit) is presented. Suggestions for further research are discussed.

Author Information

Amaro, Robert
NIST, Boulder, CO, US
Antolovich, Stephen
George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, US School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, US
Neu, Richard
George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, US School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, US
Adair, Benjamin
George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, US
Hirsch, Michael
George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, US
Fernandez-Zelaia, Patxi
George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, US
O'Rourke, Matthew
George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, US
Staroselsky, Alexander
United Technologies Research Center, East Hartford, CT, US
Pages: 15
Price: $25.00
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Details
Stock #: MPC20130049
ISSN: 2165-3992
DOI: 10.1520/MPC20130049