Microstructure formation of high pressure torsion processed (α + γ) two phase stainless steel

Mie Ota, Daiki Nanya, Sanjay Kumar Vajpai, Kei Ameyama, Kaveh Edalati, Zenji Horita

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

(α + γ) two phase stainless steel (Fe-21%Cr-4.8%Ni-1.5%Mo) powder was processed by high pressure torsion (HPT) and consolidation at room temperature. The received powder had fully α single phase due to the rapid cooling during gas atomizing process. Specimens after HPT process were heat treated at 1173K for 3.6ks. It was revealed that the decomposition of α phase to γ took place during the heat treatment. Detailed microstructure observation showed that an equiaxed (α + γ) micro-duplex structure was developed and its average grain size was approximately 3.2 micrometers. The same heat treatment given to the material without HPT resulted in a coarse two phase microstructure.Therefore, it is considered that an ultra fine grained microstructure was caused by increasing of nucleation sites for γ phase due to severe plastic deformation (SPD) of HPT process. Electron backscatter diffraction patterns (EBSD) analysis indicated that α phase has a {110}/ND strong texture, that is, the α phase seems to have single orientated coarse grain structure. The γ precipitates indicated a {111}/ND strong texture, and the crystallographic orientation relationship of Kurdjumov-Sachs was observed.

Original languageEnglish
Title of host publicationTHERMEC 2016
PublisherTrans Tech Publications Ltd
Pages1365-1368
Number of pages4
Volume879
ISBN (Print)9783035711295
DOIs
Publication statusPublished - 2017
Event9th International Conference on Processing and Manufacturing of Advanced Materials, THERMEC 2016 - Graz, Austria
Duration: May 29 2016Jun 3 2016

Publication series

NameMaterials Science Forum
Volume879
ISSN (Print)02555476

Other

Other9th International Conference on Processing and Manufacturing of Advanced Materials, THERMEC 2016
CountryAustria
CityGraz
Period5/29/166/3/16

Fingerprint

Stainless Steel
Torsional stress
torsion
stainless steels
Stainless steel
microstructure
Microstructure
Powders
heat treatment
textures
Textures
Heat treatment
process heat
gas cooling
Crystal microstructure
consolidation
atomizing
Electron diffraction
Consolidation
Diffraction patterns

All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Ota, M., Nanya, D., Vajpai, S. K., Ameyama, K., Edalati, K., & Horita, Z. (2017). Microstructure formation of high pressure torsion processed (α + γ) two phase stainless steel. In THERMEC 2016 (Vol. 879, pp. 1365-1368). (Materials Science Forum; Vol. 879). Trans Tech Publications Ltd. https://doi.org/10.4028/www.scientific.net/MSF.879.1365

Microstructure formation of high pressure torsion processed (α + γ) two phase stainless steel. / Ota, Mie; Nanya, Daiki; Vajpai, Sanjay Kumar; Ameyama, Kei; Edalati, Kaveh; Horita, Zenji.

THERMEC 2016. Vol. 879 Trans Tech Publications Ltd, 2017. p. 1365-1368 (Materials Science Forum; Vol. 879).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Ota, M, Nanya, D, Vajpai, SK, Ameyama, K, Edalati, K & Horita, Z 2017, Microstructure formation of high pressure torsion processed (α + γ) two phase stainless steel. in THERMEC 2016. vol. 879, Materials Science Forum, vol. 879, Trans Tech Publications Ltd, pp. 1365-1368, 9th International Conference on Processing and Manufacturing of Advanced Materials, THERMEC 2016, Graz, Austria, 5/29/16. https://doi.org/10.4028/www.scientific.net/MSF.879.1365
Ota M, Nanya D, Vajpai SK, Ameyama K, Edalati K, Horita Z. Microstructure formation of high pressure torsion processed (α + γ) two phase stainless steel. In THERMEC 2016. Vol. 879. Trans Tech Publications Ltd. 2017. p. 1365-1368. (Materials Science Forum). https://doi.org/10.4028/www.scientific.net/MSF.879.1365
Ota, Mie ; Nanya, Daiki ; Vajpai, Sanjay Kumar ; Ameyama, Kei ; Edalati, Kaveh ; Horita, Zenji. / Microstructure formation of high pressure torsion processed (α + γ) two phase stainless steel. THERMEC 2016. Vol. 879 Trans Tech Publications Ltd, 2017. pp. 1365-1368 (Materials Science Forum).
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