A Ti-45at.%Al alloy which was solution-treated at 1350℃ for 30 minutes and quenched in water is employed to explore mechanisms of α_2→γphase transformation. The ageing process of the quenched alloy has been in situ studied it has been found that the γ lamellae can precipitate in the α_2 matrix by two mechanisms. When The alloy is aged at 700℃, the stacking faults pre-existing in the α_2 matrix start to grow and more are generated.With the increase of ageing time and ageing temperature the density of stacking faults is increased and the γ lamellae then precipitate. This isα diffusion-controlled process. Alternatively, the γ lamellae may be formed from the α_2 matrix by 1/3(1100) shearing on the (0001) plane. The latter mechanism implies that the strain-induced transformation may occur, which is confirmed by deformation of the quenched alloy.
参考文献
| [1] | |
| [2] | |
| [3] | |
| [4] | |
| [5] | KimKW:HighTemperatureOrderedIntermetallicAlloysIV,editedbyL．A．Johnson,D．P．PopeandJ．O．Stiegler,MRSSymp．Proc．,vo1．213,1991:777．2sastrySMLandLipsittHA:MetallTrans．,1977,SA:299．3KimYW:ActaMetallMater．,1992,40:1121．4BlackburnMJ:inTheScience,TechnologyandApplicationofTitanium,eds．R．I．．JaffeeandN．E．Promiseleds,PlenumPress,NewYork,vo1．3,1970:633．5FengCR,MichelDJandCroweCR:ScriptaMetall．,1988,22:1481．6FengCR,MichelDJandCroweCR:ScriptaMetall,1989,23:241．7FengCR,MichelDJandCroweCRScriptaMetall,1989,23:1135．8YangYSandWuSK:ScriptaMetallMater．,1990 |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%