The microstructure of as-quenched 12Mn steel

Kinney, Chris; Yi, Il-Cheol; Pytlewski, K.R.; Khachaturyan, A. G.; Kim, Nack J.; Morris, J. W.

doi:10.1016/j.actamat.2016.12.001

Cited by 12 publications

(2 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The Stage IfiII transition strain was consistent for all three alloys up to approximately 5 pct strain. Figure 11(b) shows orientation image map of the a-phase, and the adjacent a-martensite plates that formed during Stage II transformation and the a-martensite plates appear to be twin related according to their orientation (highlighted with arrows in Figure 11(b)) as has been shown by Pisarik and Van Aken for athermal transformations [47] as well as Kinney et al [48] for the athermal reaction.…”

Section: B Tensile Behaviormentioning

confidence: 65%

Dynamic Strain Aging Phenomena and Tensile Response of Medium-Mn TRIP Steel

Field

Aken

2018

Metall Mater Trans A

View full text Add to dashboard Cite

Dynamic strain aging (DSA) and rapid work hardening are typical behaviors observed in medium-Mn transformation-induced plasticity (TRIP) steel. Three alloys with manganese ranging from 10.2 to 13.8 wt pct with calculated room temperature stacking fault energies varying from À 2.1 to 0.7 mJ/m 2 were investigated. Significant serrations were observed in the stress-strain behavior for two of the steels and the addition of 4.6 wt pct chromium was effective in significantly reducing the occurrence of DSA. Addition of chromium to the alloy reduced DSA by precipitation of M 23 (C,N) 6 during batch annealing at 873 K (600°C) for 20 hours. Three distinct DSA mechanisms were identified: one related to manganese ordering in stacking faults associated with e-martensite and austenite interface, with activation energies for the onset and termination of DSA being 145 and 277 kJ/mol. A second mechanism was associated with carbon diffusion in c-austenite where Mn-C bonding added to the total binding energy, and activation energies of 88 and 155 kJ/mol were measured for the onset and termination of DSA. A third mechanism was attributed to dislocation pinning and unpinning by nitrogen in a-ferrite with activation energies of 64 and 123 kJ/mol being identified. Tensile behaviors of the three medium manganese steels were studied in both the hot band and batch annealed after cold working conditions. Ultimate tensile strengths ranged from 1310 to 1404 MPa with total elongation of 24.1 to 34.1 pct. X-ray diffraction (XRD) was used to determine the transformation response of the steels using interrupted tensile tests at room temperature. All three of the processed steels showed evidence of two-stage TRIP where c-austenite first transformed to e-martensite, and subsequently transformed to a-martensite.

show abstract

Section: B Tensile Behaviormentioning

confidence: 65%

Dynamic Strain Aging Phenomena and Tensile Response of Medium-Mn TRIP Steel

Field

Aken

2018

Metall Mater Trans A

View full text Add to dashboard Cite

show abstract

“…The parent austenite phase and marten-*Corresponding author: tel. : +00-34-915206369; e-mail address: pastorma@inta.es site constituent show a Kurdjumov-Sachs relationship [3,4].…”

Section: Introductionmentioning

confidence: 99%

Measurement of martensitic packet size by EBSD in the high strength steel X38CrMoV5-1 and estimation of its influence on cleavage fracture

Pastor¹,

Vallés²,

Zubiaur³

et al. 2020

View full text Add to dashboard Cite

The crystallographic packet or microstructural unit was determined with 15 • and 5 • boundary grain misorientations in a quenched and tempered X38CrMoV5-1 steel, yielding results of 0.68 and 0.59 µm, respectively. Though both values are similar, the latter has been taken as the best to calculate the effective surface energy of cleavage fracture, γp, leading to a value of 15.8 J m −2. Thus it is demonstrated that the microstructural unit controlling crack propagation is that determined by EBSD with a 5 • misorientation angle. Other structural parameters, like the parent austenite grain size and the morphological martensitic packet, have been ruled out.

show abstract