Elastic and Plastic Deformation Behavior Studied by <i>In-Situ</i> Synchrotron X-ray Diffraction in Nanocrystalline Nickel

• Adachi Hiroki

  Department of Materials and Synchrotron Radiation Engineering, Graduate School of Engineering, University of Hyogo

• Karamatsu Yui

  Department of Materials and Chemistry, Graduate School of Engineering, University of Hyogo

• Nakayama Shota

  Department of Materials and Chemistry, Graduate School of Engineering, University of Hyogo

• Miyazawa Tomotaka

  Department of Metallurgy and Ceramics Science, Graduate School of Science and Engineering, Tokyo Institute of Technology

• Sato Masugu

  SPring-8, Japan Synchrotron Radiation Research Institute (JARSI)

• Yamasaki Tohru

  Department of Materials and Synchrotron Radiation Engineering, Graduate School of Engineering, University of Hyogo

Bibliographic Information

Other Title

• Elastic and Plastic Deformation Behavior Studied by In-Situ Synchrotron X-ray Diffraction in Nanocrystalline Nickel

Abstract

In situ XRD measurements were conducted during the tensile deformation of both submicron-grained Ni specimens fabricated by accumulative roll bonding (having a grain size of 270 nm) and nanocrystalline Ni fabricated by electrodeposition (having a grain size of 52 nm). Variations in the dislocation density and the extent of elastic deformation could be determined with a time resolution of 1.0 s based on changes in the full width at half maximum of ten Bragg peaks and in the Bragg peak shifts, respectively. The dislocation density was found to vary in four different stages. Regions I and III were the elastic and plastic deformation regions, respectively, while Region II was the transition region. Here, the dislocation density rapidly increased to a value, ρ_II, necessary for plastic deformation. Since the increase in ρ_II was inversely proportional to grain size, it is evident that nanocrystalline materials require extremely high dislocation densities for deformation to progress solely by plastic deformation. In Region IV, the multiple dislocations were rapidly annihilated by unloading associated with fracture. In the case of the nanocrystalline Ni, there was little difference in the stress distribution in the grains depending on the crystal direction during plastic deformation and, accordingly, there was only minimal variation in the residual stress in the grain with different crystal directions after unloading.

Journal

• MATERIALS TRANSACTIONS

  MATERIALS TRANSACTIONS 57 (9), 1447-1453, 2016

  The Japan Institute of Metals and Materials

Keywords

• nanocrystalline nickel
• in-situ XRD
• dislocation density
• elastic and plastic deformation

Details

• CRID: 1390001204254788864
• NII Article ID: 130005289934
• NII Article ID: 40020922392
• NII Book ID: AA1151294X
• DOI: 10.2320/matertrans.mh201505
• ISSN: 13475320
• ISSN: 13459678
• NDL BIB ID: 027571091
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I027571091
• Web Site: https://www.jstage.jst.go.jp/article/matertrans/57/9/57_MH201505/_pdf
• Text Lang: en
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed