EBSD investigation of the crystallographic features of deformation-induced martensite in stainless steel

In-situ strain induced martensitic transformation measurement and consequences for the modeling of medium Mn stainless steels mechanical behavior

“…The increase of the work hardening after a few percent of deformation is associated with the induced martensitic transformation and was also early reported [45]. In a given range of temperature and strain rate, a Portevin-Le Chatelier-like (PLC) behavior is also reported (stress serrations appear for any grade at large strain during the experiments): serrations on the stressstrain curve are associated with heterogeneous deformation and deformation band propagation, as already observed for medium manganese steels [12,[46][47][48]. When the austenitic stainless grade is very unstable, stress-induced martensite transformation is noted within the elastic domain which leads to a transient softening after the yield stress and a Lüders plateau [45].…”

Role of martensitic transformation sequences on deformation-induced martensitic transformation at high strain rates: A quasi in-situ study

“…X) colors, respectively, and the red lines indicate the twin boundaries. As seen in our previous studies, DIMT facilitates nucleation at the deformation bands and grain boundaries [25]. Thus, for α ′ -martensite nucleation, both the number and type of the deformation bands need to be considered.…”

“…3(b-g). Which were used to accurately monitor the changes in the plastic strain, as in our previous study [25]. Thus the nominal strain was obtained through the displacement increment between two Vickers indents divide by the initial distance between two Vickers indents (100 μm).…”

“…Other studies suggested that martensitic transformation sequences have a significant influence on the α ′ -martensite variant [25,35]. Wang et al's study [25,36] found significant differences in variant selection between γ→ε→α' and γ→α' sequences. In that study, the α ′ phase nucleated from ε forms with multi-variant instead of single-variant α ′ -martensite.…”

“…6. The martensite variants are numbered based on Morito et al's study [31] and our previous study [25], and the statistical results are shown in Fig. 7(a) and (b).…”