کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
777613 | 1463767 | 2014 | 5 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Microstructure degradation in high temperature fatigue of TiAl alloy Microstructure degradation in high temperature fatigue of TiAl alloy](/preview/png/777613.png)
Low cycle fatigue properties of lamellar TiAl with 8 at.% Nb were studied at four temperatures: room temperature, 700, 750 and 800 °C. Up to 750 °C, stable cyclic behaviour is observed while cyclic softening is characteristic for 800 °C. The strength of the alloy is still high even at 800 °C. The TEM observation did not reveal any substantial changes in the microstructure due to the cycling at RT. At 750 °C, the lamellar structure was in some places destroyed by cyclic plastic straining and pure γ-phase islands with high density of dislocation debris were formed. At 800 °C, the domains without lamellar structure cover about 10% of volume and are almost dislocation free. The destruction of lamellar microstructure and possible annealing of dislocation debris is the reason for marked cyclic softening at 800 °C.
Journal: International Journal of Fatigue - Volume 65, August 2014, Pages 28–32