Strain Hardening by Formation of Nanoplatelets

  1. Prof. Dr. Michael Zehetbauer2 and
  2. Prof. Ruslan Z. Valiev3
  1. K. Han,
  2. Y. Xin and
  3. A. Ishmaku

Published Online: 28 JAN 2005

DOI: 10.1002/3527602461.ch2f

Nanomaterials by Severe Plastic Deformation

Nanomaterials by Severe Plastic Deformation

How to Cite

Han, K., Xin, Y. and Ishmaku, A. (2004) Strain Hardening by Formation of Nanoplatelets, in Nanomaterials by Severe Plastic Deformation (eds M. Zehetbauer and R. Z. Valiev), Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, FRG. doi: 10.1002/3527602461.ch2f

Editor Information

  1. 2

    Institut für Materialphysik, Universität Wien, Boltzmanngasse 5, 1090 Wien, Austria

  2. 3

    Institute of Physics of Advanced Materials, Ufa State Aviation Technical University, 12 K. Marks Str., Ufa, 450 000, Russia

Author Information

  1. National High Magnetic Field Laboratory, Florida State University, 1800 E Paul Dirac Dr., Tallahassee, Fl, USA

Publication History

  1. Published Online: 28 JAN 2005
  2. Published Print: 25 FEB 2004

ISBN Information

Print ISBN: 9783527306596

Online ISBN: 9783527602469

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Keywords:

  • strain hardening;
  • formation of nanoplatelets;
  • MP35N

Summary

The strengthening mechanisms of MP35N (35wt%Co-35wt%Ni-20wt%Cr-10wt%Mo) were studied in order to explore the maximum strength achievable in such alloys. Room temperature rolling introduces both high density of dislocations and nanoplatelets in the fcc matrix. The formation of the nanoplatelets is considered diffusionless. The main mechanism is the very high rate of strain hardening that develops dynamically from the high-dislocation-density substructure and high density of nanoplatelets. The deformation also introduces {110} <112> texture and the rotation of the annealing twin boundaries. The habit planes of the nanoplatelets are on {111} and the thickness is about a few atomic layers. The formation of the platelets and dislocations strengths the fcc matrix significantly. After materials were deformed and aged, the MP35N can reach hardness of 5647±78 MPa and yield strength of 2125 MPa at room temperature. The further strengthening by aging can be related to the increase of the total length of the nanoplatelets without significantly increasing the thickness of the platelets. Deformation at 77 K increases the work hardening rate, indicating further formation of nanoplatelets and dislocations.