Study on Ferrite Intragranular Nucleation in a V-Microalloyed Steel

S.F. Medina; Manuel Gómez; J.I. Chaves; P.P. Gómez; P. Adeva

doi:10.4028/www.scientific.net/MSF.500-501.371

Paper Titles

Contribution to the Understanding of Austenite Stability in a 12Cr-9Ni-4Mo Maraging Steel
p.339

Microstructure Evolution in Fine-Grained Microalloyed Steels
p.347

Factors Limiting the Achievable Ferrite Grain Refinement in Hot Worked Microalloyed Steels
p.355

Processing and Stability of Ultrafine Grained Structures in Some Microalloy Steels
p.363

Study on Ferrite Intragranular Nucleation in a V-Microalloyed Steel
p.371

In Situ X-Ray Diffraction Measurements of Deformation-Induced Austenite to Martensite Transformation in a Multiphase TRIP Steel
p.379

Characterisation and Quantification of Complex Bainitic Microstructures in High and Ultra-High Strength Linepipe Steels
p.387

Austenite Decomposition in Low Carbon Steels with Microalloy Additions
p.395

Modeling Ferrite Grain Size Distributions during the Transformation of Hot Worked Austenite
p.403

HomeMaterials Science ForumMaterials Science Forum Vols. 500-501Study on Ferrite Intragranular Nucleation in a...

Study on Ferrite Intragranular Nucleation in a V-Microalloyed Steel

Abstract:

The intragranular nucleation of ferrite has been studied in a V-microalloyed steel (C=0.102; Mn=1.479; V=0.140; N=0.016, %wt). By means of hot torsion tests, recrystallizationprecipitation-time-temperature (RPTT) diagrams have been drawn which show the precipitation kinetics and the recrystallization-precipitation interaction at any temperature. RPTT diagrams were determined at two strains, 0.20 and 0.35 respectively. Deformation tests were carried out at 890°C and different holding times, corresponding to moments before the start of precipitation, during precipitation and after precipitation had ended, respectively. In order to relate the precipitation state with the intragranular nucleation, the strengthening of austenite was measured taking into account the non-recrystallized austenite fraction prior to the phase transformation. In this way, the possibility of V-nitrides acting as nucleation sites was evaluated by comparison of ferrite grain size versus holding time. Thus it was found that the precipitate size and precipitated volume are influencing the intragranular nucleation, although this is not a strong influence.