Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

Full sintering of powdered-metal bodies in a microwave field

Nature volume 399, pages 668–670 (1999)Cite this article

An Erratum to this article was published on 16 September 1999

Abstract

The use of microwaves to process absorbing materials was studied intensively in the 1970s and 1980s, and has now been applied to a wide variety of materials1,2,3,4. Initially, success in microwave heating and sintering was confined mainly to oxide and some non-oxide ceramics5,6,7,8,9,10,11; but recently the technique has been extended to carbide semimetals12,13,14 used in cutting tools. Here we describe the microwave sintering of powdered metals to full density. We are able to sinter a wide range of standard powdered metals from commercial sources using a 2.45-GHz microwave field, yielding dense products with better mechanical properties than those obtained by conventional heating. These findings are surprising in view of the reflectivity of bulk metals at microwave frequencies. The ability to sinter metals with microwaves should assist in the preparation of high-performance metal parts needed in many industries, for example, in the automotive industry.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Diagram of microwave system for sintering of powdered-metal parts.
Figure 2: Optical micrographs of two sets of ‘green’ (that is, unsintered) and microwave-sintered powdered–metal parts processed at 1,200?°C for 30 minutes.

Similar content being viewed by others

References

  1. Clark, D. & Sutton, W. H. Microwave processing of materials. Annu. Rev. Mater. Sci. 26, 299– 331 (1996).

    Article  ADS  CAS  Google Scholar 

  2. Schiffman, R. F. Commercializing microwave systems: Paths to success or failure. Ceram. Trans. 59, 7–17 ( 1995).

    Google Scholar 

  3. Katz, J. D. Microwave sintering of ceramics. Annu. Rev. Mater. Sci. 22, 153–170 (1992).

    Article  ADS  CAS  Google Scholar 

  4. Sutton, W. Microwave processing of ceramics: an overview. Mater. Res. Soc. Symp. Proc. 269, 3–19 ( 1992).

    Article  CAS  Google Scholar 

  5. Sutton, W. Microwave processing of ceramic materials. Am. Ceram. Soc. Bull. 68, 376–386 ( 1989).

    CAS  Google Scholar 

  6. Fang, Y., Agrawal, D. K., Roy, D. M. & Roy, R. Fabrication of transparent hydroxyapatite ceramics by microwave processing. Mater. Lett. 23, 147–151 (1995).

    Article  CAS  Google Scholar 

  7. Agrawal, D. K., Fang, Y., Roy, D. M. & Roy, R. Mater. Res. Soc. Symp. Proc. 269, 231–236 ( 1992).

    Google Scholar 

  8. Fang, Y., Agrawal, D. K., Roy, D. M. & Roy, R. Fabrication of porous hydroxyapatite ceramics by microwave processing. J. Mater. Res. 7, 490–494 ( 1992).

    Article  ADS  CAS  Google Scholar 

  9. Fang, Y., Roy, R., Agrawal, D. K. & Roy, D. M. Transparent mullite ceramics from diphasic aerogels by microwave and conventional processing. Mater. Lett. 28, 11–15 (1996).

    Article  CAS  Google Scholar 

  10. Fang, Y., Agrawal, D. K., Roy, D. M. & Roy, R. Microwave sintering of calcium strontium zirconium phosphate ceramics. Ceram. Trans. 36, 109 (1993).

    CAS  Google Scholar 

  11. Fang, Y., Agrawal, D. K., Roy, D. & Roy, R. Microwave sintering of hydroxyapatite-based composites. Ceram. Trans. 36 , 397 (1993).

    CAS  Google Scholar 

  12. Roy, R., Agrawal, D., Cheng, J. P. & Mathis, M. Microwave processing: triumph of applications-driven science in WC-composites and ferroic titanates. Ceram. Trans. 80, 3–26 (1997).

    CAS  Google Scholar 

  13. Cheng, J. P., Agrawal, D. K., Komarneni, S., Mathis, M. & Roy, R. Microwave processing of WC-Co composites and ferroic titanates. Mater. Res. Innov. 1, 44–52 (1997).

    Article  CAS  Google Scholar 

  14. Gerdes, T. & Willert-Porada, M. Mater. Res. Soc. Symp. Proc. 347, 531–537 ( 1996).

    Google Scholar 

  15. Walkiewicz, J. W., Kazonich, G. & McGill, S. L. Microwave heating characteristics of selected minerals and compounds. Min. Metall. Processing 5, 39–42 (1988).

    CAS  Google Scholar 

  16. Willert-Porada, M., Gerdes, T., Rodiger, K. & Kolaska, H. Einsatz von Mikrowellen zum Sintern pulvermetallurgischer Prudukte. Metall 50, 744–752 (1996).

    CAS  Google Scholar 

  17. Nishitani, T. Method for sintering refractories and an apparatus therefor.US Patent No. 4147911 (1979).

  18. Whittaker, A. G. & Mingos, D. M. Microwave-assisted solid-state reactions involving metal powders. J. Chem. Soc. Dalton Trans. 2073–2079 (1995).

  19. German, R. M. Sintering Theory and Practice(Wiley, New York, 1996 ).

    Google Scholar 

  20. Gedevanishvili, S., Agrawal, D. & Roy, R. Microwave combustion synthesis and sintering of intermetallics and alloys. Mater. Sci. Lett.(submitted).

  21. Cherradi, A., Desgardin, G., Provost, J. & Raveau, B. Electric magnetic field contributions to the microwave sintering of ceramics. In Electroceramics IV Vol. II,(eds. Wasner, R., Hoffmann, S., Bonnenberg, D. & Hoffmann, C.) 1219–1224 (RWTN, Aachen, 1994).

  22. Shanker, B. & Lakhtakia, A. Extended Maxwell Garnett formalism for composite adhesives for microwave-assisted adhesion of polymer surfaces. J. Compos. Mater. 27, 1203– 1213 (1993).

    Article  ADS  CAS  Google Scholar 

Download references

Acknowledgements

We thank J. Kosco for providing powdered-metal components. We also thank the approximately 20 corporations that supported the early stages of this work, which is now supported by the Electric Power Research Institute, the Keystone Powder Metal Company and the Ben Franklin Technology Center.

Author information

Authors and Affiliations

  1. Materials Research Laboratory, The Pennsylvania State University, University Park, Pennsylvania, 16802, USA

    Rustum Roy, Dinesh Agrawal, Jiping Cheng & Shalva Gedevanishvili

Authors
  1. Rustum Roy
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Dinesh Agrawal
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Jiping Cheng
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Shalva Gedevanishvili
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Dinesh Agrawal.

Supplementary Information

Rights and permissions

Reprints and permissions

About this article

Cite this article

Roy, R., Agrawal, D., Cheng, J. et al. Full sintering of powdered-metal bodies in a microwave field. Nature 399, 668–670 (1999). https://doi.org/10.1038/21390

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/21390

This article is cited by

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing