ANALYSIS OF CREEP-FATIGUE MODELS IN NICKEL BASE SUPERALLOYS

C. Moura Branco  F.B.Santos       

Anales de la Mecánica de la Fractura, nº 16 . 1999 . Pág. 155 -160
Ver (.pdf): Anales16-021

Resumen: The paper presents the final results of a detailed study carried out in the nickel base superalloy IN718, used in turbine discs where fatigue and creep crack growth rate data (FCGR and CCGR) was obtained at 600 and 700°C in CT and CC (comer crack) specimens, tested at different values of stress ratio and dwell time at maximum load (frequency). In the second part of the paper, a presentation is made of available creep-fatigue models, and also the esults obtained with a computer program developed by the authors, which is able to make a detailed comparison between the experimental data obtained for the FCGR in creep-fatigue situations and the equivalent results predicted by the different models. The results predicted by the models are discussed in terms or variations dueto specimen type (CT or CC), stress ratio, temperature, frequency and, also, stress state.

LocalizaciónTorremolinos, Málaga

ICEMS/IST Avda, Rovisco Pais, 1096 Lisbon Codex, Portugal
Departamento de Engenharia Electromedinica, Universidade da Beira Interior. Rua Marques d'Avila e Bolama, 6200 Covilha, Portugal