The mechanism of superplasticity in fine grained Ti 33Al 3Cr 0 5Mo(%) alloy was investigated by tensile test at 1 000 ℃. Electron microscopic studies showed a lot of dislocation pile up, walls and nets after superpla...The mechanism of superplasticity in fine grained Ti 33Al 3Cr 0 5Mo(%) alloy was investigated by tensile test at 1 000 ℃. Electron microscopic studies showed a lot of dislocation pile up, walls and nets after superplastic deformation, and most of the dislocations originated either from grain boundaries or from α 2 particles, located both in grain boundaries and within gamma grains. In addition, dynamic recrystallization occured.Therefore, it was suggested that the superplastic deformation in the present fine grained TiAl based alloy is grain boundary sliding accommodated by dislocation motion and dynamic recrystallization.展开更多
Superplastic properties and microstructural evolution of a Ti-24Al-14Nb-3V-0.5Mo (at. pct) intermetallic alloy were studied. Optimum superplastic properties were obtained for temperatures in the interval 960℃≤5 T≤5...Superplastic properties and microstructural evolution of a Ti-24Al-14Nb-3V-0.5Mo (at. pct) intermetallic alloy were studied. Optimum superplastic properties were obtained for temperatures in the interval 960℃≤5 T≤5980℃. The apparent activation energy in the superplastic regime was determined and the deformation mechanism was also discussed. Based on the studies, a curve panel with three sheets sandwich structure was fabricated successfully. The microstructures corresponding to different strain in the part were also studied.展开更多
文摘The mechanism of superplasticity in fine grained Ti 33Al 3Cr 0 5Mo(%) alloy was investigated by tensile test at 1 000 ℃. Electron microscopic studies showed a lot of dislocation pile up, walls and nets after superplastic deformation, and most of the dislocations originated either from grain boundaries or from α 2 particles, located both in grain boundaries and within gamma grains. In addition, dynamic recrystallization occured.Therefore, it was suggested that the superplastic deformation in the present fine grained TiAl based alloy is grain boundary sliding accommodated by dislocation motion and dynamic recrystallization.
文摘Superplastic properties and microstructural evolution of a Ti-24Al-14Nb-3V-0.5Mo (at. pct) intermetallic alloy were studied. Optimum superplastic properties were obtained for temperatures in the interval 960℃≤5 T≤5980℃. The apparent activation energy in the superplastic regime was determined and the deformation mechanism was also discussed. Based on the studies, a curve panel with three sheets sandwich structure was fabricated successfully. The microstructures corresponding to different strain in the part were also studied.
