EBSD characterization of cryogenically rolled type 321 austenitic stainless steel

Electron backscatter diffraction was applied to investigate microstructure evolution during cryogenic rolling of type 321 metastable austenitic stainless steel. As expected, rolling promoted deformation-induced martensitic transformation which developed preferentially in deformation bands. Because a large fraction of the imposed strain was accommodated by deformation banding, grain refinement in the parent austenite phase was minima

Superplastic behavior of fine-grained Al-Mg-Li alloy

The superplastic behavior of fine-grained 1420 Al-Mg-Li alloy was investigated using a modern electron microscopy technique based on automatic analysis of electron backscattered diffraction patterns (EBSD analysis

EBSD study of superplastically strained Al-Mg-Li alloy

In this study, electron back scatter diffraction (EBSD) was employed to examine the microstructure evolved during superplastic deformation of advanced Al-Mg-Li alloy. In contrast to the widely-accepted conception of superplasticity, the microstructure was found to be characterized by elongated grains, a notable fraction of low-angle boundaries, and a distinct (though a very weak) crystallographic texture. All these observations suggested a significant activity of intragranular slip

EBSD characterization of cryogenically rolled type 321 austenitic stainless steel

Electron backscatter diffraction was applied to investigate microstructure evolution during cryogenic rolling of type 321 metastable austenitic stainless steel. As expected, rolling promoted deformation-induced martensitic transformation which developed preferentially in deformation bands. Because a large fraction of the imposed strain was accommodated by deformation banding, grain refinement in the parent austenite phase was minimal. The martensitic transformation was found to follow a general orientation relationship, {111}γ||{0001}ε||{110}α′ and 〈110〉γ||〈11-20〉ε||〈111〉α′, and was characterized by noticeable variant selection

Martensite-to-austenite reversion and recrystallization in cryogenically-rolled type 321 metastable austenitic steel

The annealing behavior of cryogenically-rolled type 321 metastable austenitic steel was established. Cryogenic deformation gave rise to martensitic transformation which developed preferentially within deformation bands. Subsequent annealing in the range of 600 C to 700 C resulted in reversion of the strain-induced martensite to austenite. At 800 C, the reversion was followed by static recrystallization. At relatively-low temperatures, the reversion was characterized by a very strong variant selection, which led to the restoration of the crystallographic orientation of the coarse parent austenite grains. An increase in the annealing temperature relaxed the variant-selection tendency and provided subsequent recrystallization thus leading to significant grain refinement. Nevertheless, a significant portion of the original coarse grains was found to be untransformed and therefore the fine-grain structure was fairly heterogeneous

Microstructural evolution during superplastic deformation of Al-Mg-Li alloy : dynamic recrystallization or grain-boundary sliding?

In this work, advanced capabilities of electron backscatter diffraction (EBSD) were applied to evaluate the role played dynamic recrystallization during superplastic deformation of a typical fine-grained material. It was found that the dynamic recrystallization occurred only locally and thus provided only minor contribution to microstructural evolution. Hence, the preservation of the nearly-equiaxed grain morphology, inherent to the superplasticity phenomenon, cannot be attributed to the dynamic recrystallization