Advertisement

A new method of characterizing equivalent strain for equal channel angular processing

  • Jun Zhao (赵军)
  • Zhen-hua Wang (王振华)
  • Shu-hua Sun (孙淑华)
  • De-li Zhao (赵德利)
  • Li-guo Ren (任利国)
  • Wan-tang Fu (傅万堂)Email author
Article

Abstract

In order to establish the quantitative relationship between equivalent strain and the performance index of the deformed material within the range of certain passes for equal channel angular processing (ECAP), a new approach to characterize the equivalent strain was proposed. The results show that there exists better accordance between mechanical property (such as hardness or strength) and equivalent strain after rolling and ECAP in a certain range of deformation amount, and Gauss equation can be satisfied among the equivalent strain and the mechanical properties for ECAP. Through regression analysis on the data of hardness and strength after the deformation, a more generalized expression of equivalent strain for ECAP is proposed as: ɛ=k0exp[−(k1Mk2)2], where M is the strength or hardness of the material, k1 is the modified coefficient (k1∈(0, 1)), k0 and k2 are two parameters dependent on the critical strain and mechanical property that reaches saturation state for the material, respectively. In this expression the equivalent strain for ECAP is characterized novelly through the mechanical parameter relating to material property rather than the classical geometry equation.

Key words

equal channel angular processing (ECAP) equivalent strain mechanical property characterizing method 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. [1]
    SEGAL V M. Materials processing by simple shear [J]. Materials Science and Engineering A, 1995, A197: 157–164.CrossRefGoogle Scholar
  2. [2]
    IWAHASHI Y, WANG J T, HORITA Z, NEMOTO M, TERENCE G L. Principle of equal channel angular pressing for the processing of ultra-fine grained materials [J]. Scripta Materialia, 1996, 35(2): 143–146.CrossRefGoogle Scholar
  3. [3]
    GOFORTH R E, HARTWIG K T, CORNWELL L R. Severe plastic deformation of materials by equal channel angular extrusion (ECAE) [C]// LOWE T C, VALIEV R Z. Investigations and Applications of Severe Plastic Deformation Dordrecht: Kluwer Academic Publishers, 2000.Google Scholar
  4. [4]
    LEE J C, SEOK H K, SUH J Y. Microstructural evolutions of the Al strip prepared by cold rolling and continuous equal channel angular pressing [J]. Acta Materialia, 2002, 50: 4005–4019.CrossRefGoogle Scholar
  5. [5]
    TORIZUKA S, OHMORI A, NARAYANA MURTY S V S, NARAYANA M, KOTOBU N. Effect of strain on the microstructure and mechanical properties of multi-pass warm caliber rolled low carbon steel [J]. Scripta Materialia, 2006, 54: 563–568.CrossRefGoogle Scholar
  6. [6]
    SATO Y S, URATA M, KOKAWA H, KEISUKE I. Hall-Petch relationship in friction stir welds of equal channel angular pressed aluminium alloys [J]. Materials Science and Engineering A, 2003, A354: 298–305.CrossRefGoogle Scholar
  7. [7]
    DU Zhong-ze, HUANG Jun-xia, FU Han-guang, WANG Jing-tao, ZHAO Xi-cheng. Microstructure and mechanical property of 65Mn steel after severe plastic deformation [J]. Journal of Jilin University: Engineering and Technology, 2006, 36(2): 143–147. (in Chinese)Google Scholar
  8. [8]
    FURUNO K, AKAMATSU H, OHISHI K, FURUKAWA M, HORITA Z, TERENCE G L. Microstructural development in equal-channel angular pressing using a 60° die [J]. Acta Materialia, 2004, 52: 2497–2507.CrossRefGoogle Scholar
  9. [9]
    HORITA Z, FUJINAMI T, NEMOTO M, LANGDON T G. Improvement of mechanical properties for Al alloys using equal-channel angular pressing [J]. Journal of Materials Processing Technology, 2001, 117: 288–292.CrossRefGoogle Scholar
  10. [10]
    DALLA T F, LAPOVOK R, SANDLIN J, THOMSON P F, DAVIES C H J, PERELOMA E V. Microstructures and properties of copper processed by equal channel angular extrusion for 1–16 passes [J]. Acta Materialia, 2004, 52: 4819–4832.CrossRefGoogle Scholar
  11. [11]
    KO Y G, SHIN D H, PARK K T, CHONG S L. An analysis of the strain hardening behavior of ultra-fine grain pure titanium [J]. Scripta Materialia, 2006, 54: 1785–1789.CrossRefGoogle Scholar
  12. [12]
    MATHIS K, GUBICZA J, NAM N H. Microstructure and mechanical behavior of AZ91 Mg alloy processed by equal channel angular pressing [J]. Journal of Alloys and Compounds, 2005, 394: 194–199.CrossRefGoogle Scholar
  13. [13]
    WANG Xiao-gang. Microstructures and mechanical properties of equal channel angular presses ultra-low carbon steel [D]. Xi’an: Xi’an University of Architecture and Technology, 2004. (in Chinese)Google Scholar
  14. [14]
    SHIN D H, SEO C W, KIM J, KYUNG T P, WUNG Y C. Microstructures and mechanical properties of equal-channel angular pressed low carbon steel [J]. Scripta Materialia, 2000, 42: 695–699.CrossRefGoogle Scholar
  15. [15]
    WANG Jing-tao, XU Cheng, DU Zhong-ze, QU Guo-zhong, TERENCE G L. Microstructure and properties of a low-carbon steel processed by equal-channel angular pressing [J]. Materials Science and Engineering A, 2005, A410/411: 312–315.CrossRefGoogle Scholar
  16. [16]
    XU Shu-bo, ZHAO Guo-qun, LUAN Yi-guo, GUAN Yan-jin. Numerical studies on processing routes and deformation mechanism of multi-pass equal channel angular pressing processes [J]. Journal of Materials Processing Technology, 2006, 176: 251–259.CrossRefGoogle Scholar
  17. [17]
    WU Y, BAKER I. An experimental study of equal channel angular extrusion [J]. Scripta Materialia, 1997, 37(4): 437–442.CrossRefGoogle Scholar

Copyright information

© Central South University Press and Springer-Verlag GmbH 2009

Authors and Affiliations

  • Jun Zhao (赵军)
    • 1
    • 2
    • 3
  • Zhen-hua Wang (王振华)
    • 1
    • 2
  • Shu-hua Sun (孙淑华)
    • 1
    • 2
  • De-li Zhao (赵德利)
    • 1
    • 2
  • Li-guo Ren (任利国)
    • 1
    • 2
  • Wan-tang Fu (傅万堂)
    • 1
    • 2
    Email author
  1. 1.State Key Laboratory of Metastable Materials Science and TechnologyYanshan UniversityQinhuangdaoChina
  2. 2.College of Materials Science and EngineeringYanshan UniversityQinhuangdaoChina
  3. 3.North China Institute of Aerospace EngineeringLangfangChina

Personalised recommendations