Advertisement

Journal of Materials Science

, Volume 44, Issue 3, pp 869–874 | Cite as

Solid–liquid structural break-up in M2 tool steel for semi-solid metal processing

  • M. Z. OmarEmail author
  • H. V. Atkinson
  • A. A. Howe
  • E. J. Palmiere
  • P. Kapranos
  • M. J. Ghazali
Article

Abstract

The success of semi-solid metal processing mostly depends on the formation of suitable starting microstructure, which must consist of solid metal spheroids in a liquid matrix. Various methods of obtaining this structure have been established; they include recrystallisation and partial melting (RAP), strain-induced melt-activated (SIMA), or simple mechanical stirring, to name a few. These methods, as widely discussed, have mostly been applied with light alloys, mainly aluminium based. This article discusses solid–liquid structural break-up in M2 tool steel subjected to a direct re-melting procedure from the as-annealed condition. The role of carbide dissolution in the grain boundary liquation of the steel is described. This leads to the production of near spheroidal solid grains in a liquid matrix, a microstructure suitable for the thixoforming process. Microstructural examination revealed that carbide particles contained in bands at 1220 °C slowly disappeared with temperature. At 1300 °C, the solid grains seemed to be free from carbides. Most of the carbides had now re-precipitated at the grain boundaries. Thixoforming carried out at 1340 and 1360 °C revealed the thixotropic properties of the semi-solid metal slurries. The results indicate a widening of the range of potential routes to thixoformable microstructures.

Keywords

Carbide Tool Steel Carbide Particle Liquid Matrix Semisolid State 

Notes

Acknowledgements

The authors wish to thank Universiti Kebangsaan Malaysia (a.k.a National University of Malaysia), Malaysia, for financial assistance, and the University of Sheffield, UK, for the provision of laboratory facilities.

References

  1. 1.
    Spencer DB, Mehrabian R, Flemings MC (1972) Metall Mater Trans 3A:1925CrossRefGoogle Scholar
  2. 2.
    Flemings MC (1991) Metall Trans A 22A:957CrossRefGoogle Scholar
  3. 3.
    Kirkwood DH (1994) Int Mater Rev 39(5):173CrossRefGoogle Scholar
  4. 4.
    Fan Z (2002) Int Mater Rev 47(2):49CrossRefGoogle Scholar
  5. 5.
    Legoretta EC, Atkinson HV, Jones H (2008) J Mater Sci 43:5456. doi: https://doi.org/10.1007/s10853-008-2829-1 CrossRefGoogle Scholar
  6. 6.
    Nohn B, Morjan U, Hartmann D (2000) In: Proceedings of the 6th international conference on semi-solid processing of alloys and composites, Turin, Italy. Edimet Spa, Brescia, pp 265–272Google Scholar
  7. 7.
    Omar MZ, Atkinson HV, Palmiere EJ, Howe AA, Kapranos P (2004) Steel Res Int 75(8/9):552CrossRefGoogle Scholar
  8. 8.
    Omar MZ, Palmiere EJ, Howe AA, Atkinson HV, Kapranos P (2005) Mater Sci Eng A 395:53CrossRefGoogle Scholar
  9. 9.
    Puttgen W, Bleck W, Hirt G, Shimahara H (2007) Adv Eng Mater 9(4):231CrossRefGoogle Scholar
  10. 10.
    Kapranos P, Kirkwood DH, Sellars CM (1993) J Phys IV Colloque C7, Suppl J Phys III 3:835Google Scholar
  11. 11.
    Kapranos P, Kirkwood DH, Sellars CM (1996) In: Proceedings of the 4th international conference on semi-solid processing of alloys and composites, The University of Sheffield, Sheffield, UK, pp 306–311Google Scholar
  12. 12.
    Kapranos P, Ward PJ, Atkinson HV, Kirkwood DH (2000) Mater Des 21:387CrossRefGoogle Scholar
  13. 13.
    American Society for Testing and Materials (1996) ASTM E 112-96Google Scholar
  14. 14.
    American Society for Testing and Materials (1999) ASTM E 562-99Google Scholar
  15. 15.
    Roberts GA, Hamaker JC Jr, Johnson AR (1971) Tool steels, 3rd edn. American Society for Metals, Metals ParkGoogle Scholar
  16. 16.
    Omar MZ, Palmiere EJ, Howe AA, Atkinson HV, Kapranos P (2004) In: Proceedings of the 8th international conference on semi-solid processing of alloys and composites, Limassol, Cyprus. North American Die Casting Association, WheelingGoogle Scholar
  17. 17.
    Honeycombe RWK, Bhadeshia HKDH (1995) Steels: microstructure and properties. Edward Arnold, UKGoogle Scholar
  18. 18.
    Meuser H, Bleck W (2001) Steel Res Int 72(7):271CrossRefGoogle Scholar
  19. 19.
    Meuser H, Bleck W (2002) In: 7th International conference on semisolid processing of alloys and composites, Tsukuba, Japan, pp 349–354Google Scholar
  20. 20.
    Dienes GJ, Klemm HF (1946) J Appl Phys 17:458CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • M. Z. Omar
    • 1
    Email author
  • H. V. Atkinson
    • 2
  • A. A. Howe
    • 3
  • E. J. Palmiere
    • 3
  • P. Kapranos
    • 3
  • M. J. Ghazali
    • 1
  1. 1.Department of Mechanical and Materials EngineeringNational University of MalaysiaBangi, SelangorMalaysia
  2. 2.Department of EngineeringUniversity of LeicesterLeicesterUK
  3. 3.Department of Engineering MaterialsThe University of SheffieldSheffieldUK

Personalised recommendations