Quantification of large deformation with punching in dual phase steel and change of its' microstructure - Part II: Local strain mapping of dual phase steel by a combination technique of electron backscatter diffraction and digital image correlation methods

Nobuo Nakada, Ken Ichi Ikeda, Hiroshi Shuto, Tatsuo Yokoi, Toshihiro Tsuchiyama, Satoshi Hata, Hideharu Nakashima, Setsuo Takaki

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

To evaluate heterogeneous strain distribution developed by pre-deformations in dual phase (DP) steel accurately, a combinational technique of Electron Backscatter Diffraction (EBSD) and Digital Image Correlation (DIC) methods was newly introduced in this study. A good correlation is established between kernel average misorientation calculated by EBSD and local equivalent strain measured by DIC in ferrite matrix of DP steels regardless of the difference in deformation process, which means that an EBSD orientation map can be easily converted into an applicative strain map by employing the individual correlation formula. This new technique reveals that very high strain region is locally formed within dozens of micrometer from the punched edge in a punched DP steel. On the other hand, hard martensite grains dispersed in DP steel remarkably promote the heterogeneity of strain distribution in ferrite matrix. As a result, the high strain region is also developed in the form of bands in a cold-rolled DP steel by only 60% thickness reduction at least, as if it is affected by the distribution and morphology of martensite grains. In addition, the local strain mapping demonstrates that the equivalent strain of the high strain band in cold-rolled material is comparable to that of the heavily deformed edge in punched one. The very high strain band in ferrite matrix is characterized by ultrafine grained structure, which leads to the possibility for the losing ductility in ferrite matrix and the martensite cracking.

Original languageEnglish
Pages (from-to)253-259
Number of pages7
JournalTetsu-To-Hagane/Journal of the Iron and Steel Institute of Japan
Volume102
Issue number5
DOIs
Publication statusPublished - Jan 1 2016

Fingerprint

Punching
Correlation methods
Steel
Electron diffraction
steels
ferrites
microstructure
Microstructure
martensite
diffraction
strain distribution
matrices
electrons
Ferrite
Martensite
ductility
misalignment
micrometers
Ductility

All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics
  • Physical and Theoretical Chemistry
  • Metals and Alloys
  • Materials Chemistry

Cite this

@article{efcdadf10f394afd85c0de1832d96bbf,
title = "Quantification of large deformation with punching in dual phase steel and change of its' microstructure - Part II: Local strain mapping of dual phase steel by a combination technique of electron backscatter diffraction and digital image correlation methods",
abstract = "To evaluate heterogeneous strain distribution developed by pre-deformations in dual phase (DP) steel accurately, a combinational technique of Electron Backscatter Diffraction (EBSD) and Digital Image Correlation (DIC) methods was newly introduced in this study. A good correlation is established between kernel average misorientation calculated by EBSD and local equivalent strain measured by DIC in ferrite matrix of DP steels regardless of the difference in deformation process, which means that an EBSD orientation map can be easily converted into an applicative strain map by employing the individual correlation formula. This new technique reveals that very high strain region is locally formed within dozens of micrometer from the punched edge in a punched DP steel. On the other hand, hard martensite grains dispersed in DP steel remarkably promote the heterogeneity of strain distribution in ferrite matrix. As a result, the high strain region is also developed in the form of bands in a cold-rolled DP steel by only 60{\%} thickness reduction at least, as if it is affected by the distribution and morphology of martensite grains. In addition, the local strain mapping demonstrates that the equivalent strain of the high strain band in cold-rolled material is comparable to that of the heavily deformed edge in punched one. The very high strain band in ferrite matrix is characterized by ultrafine grained structure, which leads to the possibility for the losing ductility in ferrite matrix and the martensite cracking.",
author = "Nobuo Nakada and Ikeda, {Ken Ichi} and Hiroshi Shuto and Tatsuo Yokoi and Toshihiro Tsuchiyama and Satoshi Hata and Hideharu Nakashima and Setsuo Takaki",
year = "2016",
month = "1",
day = "1",
doi = "10.2355/tetsutohagane.TETSU-2015-086",
language = "English",
volume = "102",
pages = "253--259",
journal = "Tetsu-To-Hagane/Journal of the Iron and Steel Institute of Japan",
issn = "0021-1575",
publisher = "一般社団法人 日本鉄鋼協会",
number = "5",

}

TY - JOUR

T1 - Quantification of large deformation with punching in dual phase steel and change of its' microstructure - Part II

T2 - Local strain mapping of dual phase steel by a combination technique of electron backscatter diffraction and digital image correlation methods

AU - Nakada, Nobuo

AU - Ikeda, Ken Ichi

AU - Shuto, Hiroshi

AU - Yokoi, Tatsuo

AU - Tsuchiyama, Toshihiro

AU - Hata, Satoshi

AU - Nakashima, Hideharu

AU - Takaki, Setsuo

PY - 2016/1/1

Y1 - 2016/1/1

N2 - To evaluate heterogeneous strain distribution developed by pre-deformations in dual phase (DP) steel accurately, a combinational technique of Electron Backscatter Diffraction (EBSD) and Digital Image Correlation (DIC) methods was newly introduced in this study. A good correlation is established between kernel average misorientation calculated by EBSD and local equivalent strain measured by DIC in ferrite matrix of DP steels regardless of the difference in deformation process, which means that an EBSD orientation map can be easily converted into an applicative strain map by employing the individual correlation formula. This new technique reveals that very high strain region is locally formed within dozens of micrometer from the punched edge in a punched DP steel. On the other hand, hard martensite grains dispersed in DP steel remarkably promote the heterogeneity of strain distribution in ferrite matrix. As a result, the high strain region is also developed in the form of bands in a cold-rolled DP steel by only 60% thickness reduction at least, as if it is affected by the distribution and morphology of martensite grains. In addition, the local strain mapping demonstrates that the equivalent strain of the high strain band in cold-rolled material is comparable to that of the heavily deformed edge in punched one. The very high strain band in ferrite matrix is characterized by ultrafine grained structure, which leads to the possibility for the losing ductility in ferrite matrix and the martensite cracking.

AB - To evaluate heterogeneous strain distribution developed by pre-deformations in dual phase (DP) steel accurately, a combinational technique of Electron Backscatter Diffraction (EBSD) and Digital Image Correlation (DIC) methods was newly introduced in this study. A good correlation is established between kernel average misorientation calculated by EBSD and local equivalent strain measured by DIC in ferrite matrix of DP steels regardless of the difference in deformation process, which means that an EBSD orientation map can be easily converted into an applicative strain map by employing the individual correlation formula. This new technique reveals that very high strain region is locally formed within dozens of micrometer from the punched edge in a punched DP steel. On the other hand, hard martensite grains dispersed in DP steel remarkably promote the heterogeneity of strain distribution in ferrite matrix. As a result, the high strain region is also developed in the form of bands in a cold-rolled DP steel by only 60% thickness reduction at least, as if it is affected by the distribution and morphology of martensite grains. In addition, the local strain mapping demonstrates that the equivalent strain of the high strain band in cold-rolled material is comparable to that of the heavily deformed edge in punched one. The very high strain band in ferrite matrix is characterized by ultrafine grained structure, which leads to the possibility for the losing ductility in ferrite matrix and the martensite cracking.

UR - http://www.scopus.com/inward/record.url?scp=84969862450&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84969862450&partnerID=8YFLogxK

U2 - 10.2355/tetsutohagane.TETSU-2015-086

DO - 10.2355/tetsutohagane.TETSU-2015-086

M3 - Article

AN - SCOPUS:84969862450

VL - 102

SP - 253

EP - 259

JO - Tetsu-To-Hagane/Journal of the Iron and Steel Institute of Japan

JF - Tetsu-To-Hagane/Journal of the Iron and Steel Institute of Japan

SN - 0021-1575

IS - 5

ER -