کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5461051 | 1516201 | 2017 | 9 صفحه PDF | دانلود رایگان |
- Creep mechanisms of Ti3AlC2 at 900 °C are controlled by grain boundary sliding.
- Intragranular deformation involves dislocations, stacking faults and new defects.
- Intra but also intergranular deformation has to be taken into account.
The deformation mechanisms involved in the tensile creep of a Ti3AlC2 specimen deformed, at 900 °C, to a 7.5% final strain are investigated through SEM and TEM observations. Tensile creep strain rate analyses on Ti3AlC2 deformed at 900 °C enabled to identify a Norton's law with a n coefficient around 2, suggesting that creep mechanisms are controlled by grain boundary sliding. TEM observations revealed a highly heterogeneous microstructure consisting in both grains without any dislocations and grains highly defected. This intragranular deformation involves three different microstructural features: dislocations mainly confined in the basal planes and possibly organized in hexagonal networks, numerous stacking faults, and original lenticular non planar defects that likely play an important role in the sample deformation. The deformed microstructure observed and the estimated Norton coefficient suggest that intergranular deformation play an additional important role in the deformation mechanisms.
Journal: Journal of Alloys and Compounds - Volume 693, 5 February 2017, Pages 622-630