Nanocrystallization in Carbon Steels by Various Severe Plastic Deformation Processes

  1. Prof. Dr. Michael Zehetbauer2 and
  2. Prof. Ruslan Z. Valiev3
  1. Y. Todaka,
  2. M. Umemoto and
  3. K. Tsuchiya

Published Online: 28 JAN 2005

DOI: 10.1002/3527602461.ch9d

Nanomaterials by Severe Plastic Deformation

Nanomaterials by Severe Plastic Deformation

How to Cite

Todaka, Y., Umemoto, M. and Tsuchiya, K. (2004) Nanocrystallization in Carbon Steels by Various Severe Plastic Deformation Processes, 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.ch9d

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. Department of Production System Engineering, Toyohashi University of Technology, Toyohashi, Aichi 441-8580, Japan

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:

  • nanocrystallization;
  • carbon steels;
  • severe plastic deformation processes;
  • ball drop;
  • particle impact;
  • shot peening

Summary

Nanocrystalline materials have attracted considerable scientific interests in the past decade. Various severe plastic deformation methods have been proposed to produce nanocrystalline materials, such as ball milling [1,2], severe plastic torsion straining [3] and surface mechanical attrition [4,5]. Among these, extensive works have been performed on ball milling due to its simplicity, low cost and applicability to essentially all classes of materials. From our previous ball milling experiments in steels [6–9], it was found that the nanocrystalline regions have the following characteristics: 1) homogeneous structure with sharp boundary with work-hardened region, 2) ultrafine grains of less than 100 nm with almost no dislocations, 3) extremely high hardness (8 ∼ 14 GPa), 4) dissolution of cementite when it exist and 5) no recrystallization and slow grain growth by annealing. Although ball milling is a useful method to produce nanocrystalline materials, it is not suitable to study the nanocrystallization mechanism since the deformation mode is quite complex and contamination is hard to avoid. To study nanocrystallization mechanism by severe plastic deformation, methods which produces simple deformation on specimens without contamination are desired.

The purpose of the present study is to demonstrate new severe plastic deformation techniques, i.e. ball drop [10,11], particle impact and shot peening processes, to produce nanocrystalline regions on the surface of bulk steel samples. The nanocrystalline regions formed by these techniques were compared with those in ball milled powder. Finally, shot peening is proposed to be the most practical process for producing nanocrystalline regions.