High-strain-rate superplastic behavior in a super-rapidly-solidified Al-Si system alloy

Effects of microstructural evolution on superplastic deformation characteristics of a rapidly solidified Al-Li alloy

“…[9,11,14] The concept of threshold stress used as peculiar characteristics of HSRS is naturally incorporated in the theory as ⌺ g of GBS for a more general structural superplasticity, not just limited to HSRS. [7][8][9][10][11][12][13][14] In the present study, however, the RS alloy processed by the powder metallurgy route shows much smaller values of ⌺ g compared to the IM 8090 alloy, as given in Tables I and II. The alloys fabricated by a powder metallurgy route have been reported to contain, in general, a large number of fine secondary phase particles on grain boundaries to give comparatively high values of o due to their hindrance of GBS.…”

“…A alloys fabricated by ingot casting methods, it is essential common characteristic of alloys showing HSRS is that they to refine grains through thermomechanical treatment. [7][8][9][10][11][12][13][14] Efforts mation or by dynamic recrystallization during superplastic have been made to enhance superplastic and mechanical deformation. Such fine Thermomechanical treatment achieves a very fine grain grain sizes can be achieved using PM, which is preceded structure either by recrystallization after large plastic deforby rapid solidification or mechanical alloying.…”

“…Such fine Thermomechanical treatment achieves a very fine grain grain sizes can be achieved using PM, which is preceded structure either by recrystallization after large plastic deforby rapid solidification or mechanical alloying. [10][11][12][13][14] Up to the present, superplasticity is to 10 Ϫ1 /s, [7][8][9][10] generally referred to as high strain rate superevident only in nickel-base superalloys and high carbon plasticity (HSRS) in differentiation from conventional supersteels, but is not clearly verified in rapidly solidified (RS) plasticity. However, ingot cast Al-Li alloys show superproperties of alloys fabricated with this process through new plasticity at low strain rates of 10 Ϫ4 to 10 Ϫ3 /s, and thus are advanced alloy designing.…”

Microstructural design for large superplastic elongations in aluminum-base materials containing particles

“…However, the liquid phase is not always required to attain large elongations in superplastic deformation. Actually, it has been reported that aluminumbase materials attain large elongations (.200 pct) below their partial melting temperatures, [10,11,24,[25][26][27][28]30,31,33] leading to the prediction that cavity nucleation is inhibited during superplastic deformation under these conditions.…”