Structural and phase transformations in nanostructured 0.1% C-Mn-V-Ti steel during cold deformation by high pressure torsion and subsequent heating

E. G. Astafurova, S. V. Dobatkin, E. V. Naydenkin, S. V. Shagalina, G. G. Zakharova, Yu F. Ivanov

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

The structural and phase transformations which take place in low-carbon 0.1% C-Mn-V-Ti steel during deformation by high pressure torsion (HPT) and subsequent heating have been studied using transmission electron microscopy and X-ray structural analysis methods. Whatever the initial state, be it ferritic-pearlitic or martensitic (obtained by quenching from 950°C and 1180°C), HPT at room temperature leads to the formation of a nanosized oriented grain-subgrain structure. The average size of the elements of the grain-subgrain structure in the 0.1% C-Mn-V-Ti steel after severe plastic deformation is larger in the initially ferritic-pearlitic state (95 nm) than in the initially martensitic states (65 and 50 nm after quenching from 950°C and 1180°C, respectively). It is shown that quenching from 950°C and 1180°C causes the formation of the martensite of different fineness, providing, in turn, nanostructures of different dimensions and different levels of the strength properties after HPT. Quenching from 1180°C is conducive to a higher thermal stability of the HPT-induced nanocrystalline structure of the 0.1% C-Mn-V-Ti steel on account of the larger amount of vanadium carbide precipitates. It is found that HPT leads to a considerable increase in the microhardness of the 0.1% C-Mn-V-Ti steel as compared to its microhardness in the initial state (more than 3 times as high in the ferritic-pearlitic state and more than 2 times as high the initially martensitic states).

Original languageEnglish
Pages (from-to)109-120
Number of pages12
JournalNanotechnologies in Russia
Volume4
Issue number1-2
DOIs
Publication statusPublished - 1 Feb 2009

    Fingerprint

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Engineering(all)

Cite this