Study of the low cyclic behaviour of the IRIS alloy at high temperature

Soumaya Naanani (1, 2) , Muriel Hantcherli (1) , Anis Hor (2) , Catherine Mabru (2) , Jean-Philippe Monchoux (1) , Alain Couret (1)

1 CEMES - Centre d'élaboration de matériaux et d'études structurales
2 ICA - Institut Clément Ader

This paper presents experimental results on low cycle fatigue(LCF) behaviour at high temperatures of the IRIS alloy(Ti-Al48-W2-B0.08,at. %) densified by Spark Plasma Sintering (SPS). Cyclic stability isnoticed, whatever the temperature and the total strain amplitude. Fracture occurs by mixed interlamellar and translamellar modes. Transmission electron microscopy (TEM) observations reveal that deformation is mainly due to ordinary dislocations and twins, and slip and cross-slip mechanisms have been clearly evidenced, without significant contribution of climb at 800°C. It hasalsobeen established that dislocation density depends on fatigue life time rather than on stress amplitude.

Keywords: Intermetallic alloys TiAl; Spark Plasma Sintering; Low cycle fatigue

Domains: Mechanics of materials [physics.class-ph]

Soumaya Naanani, Muriel Hantcherli, Anis Hor, Catherine Mabru, Jean-Philippe Monchoux, et al.. Study of the low cyclic behaviour of the IRIS alloy at high temperature. 12th International Fatigue Congress (FATIGUE 2018), May 2018, Poitiers, France. pp.1-9. ⟨hal-01914193⟩