Hostname: page-component-586b7cd67f-tf8b9 Total loading time: 0 Render date: 2024-11-30T10:47:33.664Z Has data issue: false hasContentIssue false

Field-assisted selective-melt sintering: a novel approach to high-density ceramics

Published online by Cambridge University Press:  08 August 2013

J. Narayan*
Affiliation:
Department of Materials Science and Engineering, North Carolina State University, Centennial Campus, EB-1, Raleigh, NC 27695-7907, USA
*
Address all correspondence to J. Narayan at j_narayan@ncsu.edu
Get access

Abstract

Electrical fields can be used to heat selectively dislocations and grain boundaries to a much higher temperature compared with the bulk. This selective joule heating, if uncontrolled by limiting the current flow, can lead to melting of grain boundaries and sintering of poly- and nanocrystalline materials close to the theoretical density in a much shorter time due to fast diffusivities of the order of 10−4 to 10−5 cm2/s in the liquid. I refer to this sintering mode as selective-melt sintering, which can occur at lower overall temperatures with much lower energy consumption compared with conventional sintering involving solid-state diffusion.

Type
Research Letters
Copyright
Copyright © Materials Research Society 2013 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Narayan, J., Weeks, R.A., and Sonder, E.: Aggregation of defects and thermal-electric breakdown in MgO. J. Appl. Phys. 49, 59775981 (1978).CrossRefGoogle Scholar
2.Weeks, R.A., Narayan, J., and Sonder, E.: Electric breakdown in MgO crystals at elevated temperature. Phys. Stat. Solidi 70, 631639 (1982).CrossRefGoogle Scholar
3.Sonder, E., Kelton, K.F., Pigg, J.C., and Weeks, R.A.: The effect of electric current on the conductivity of MgO single crystals at temperatures above 1300 K. J. Appl. Phys. 49, 59715976 (1978).CrossRefGoogle Scholar
4.Tsang, K.L., Chen, Y.: Suppression of dielectric breakdown in MgO crystals at high temperatures by impurity doping. J. Appl. Phys. 54, 45314535 (1983).CrossRefGoogle Scholar
5.Yang, D. and Conrad, H.: Influence of an electric field on the superplastic deformation of 3Y-TZP. Scr. Mater. 36, 14311435 (1997).Google Scholar
6.Yang, D. and Conrad, H.: Influence of an electric field on grain growth in extruded NaCl. Scr. Mater. 38, 14431448 (1998).Google Scholar
7.Conrad, H. and Yang, D.: Influence of an applied dc electric field on the plastic deformation kinetics of oxide ceramics. Philos. Mag. 90, 11411157 (2010).Google Scholar
8.Conrad, H. and Yang, D.: Dependence of the sintering rate and related grain size of yttria-stabilized polycrystalline zirconia (3Y-TZP) on the strength of an applied DC electric field. Mater. Sci. Eng. A 528, 85238529 (2011).CrossRefGoogle Scholar
9.Groza, J.R. and Zavaliangos, A.: Sintering activation by external electrical field. Mater. Sci. Eng. A 287, 171177 (2000).CrossRefGoogle Scholar
10.Munir, Z.A., Anselmi-Tamburini, U., and Ohyanagi, M.: The effect of electric field and pressure on the synthesis and consolidation of materials: a review of the spark plasma sintering method. J. Mater. Sci. 41, 763777 (2006).Google Scholar
11.Risbud, S.H., Groza, J.R., and Kim, M.J.: Clean grain boundaries in aluminium nitride ceramics densified without additives by a plasma-activated sintering process. Philos. Mag. 69, 525533 (1994).CrossRefGoogle Scholar
12.Wan, J., Gasch, M.J., and Mukherjee, A.K.: Silicon nitride–silicon carbide nancocomposites fabricated by electric-field-assisted sintering. J. Am. Ceram. Soc. 86, 526528 (2003).Google Scholar
13.Raj, R., Cologna, M., and Francis, J.S.C.: Influence of externally imposed and internally generated electrical fields on grain growth, diffusional creep, sintering and related phenomena in ceramics. J. Am. Ceram. Soc. 94, 19411965 (2011).CrossRefGoogle Scholar
14.Cologna, M., Francis, J.S.C., and Raj, R.: Field assisted and flash sintering of alumina and its relationship to conductivity and MgO-doping. J. Eur. Ceram. Soc. 31, 28272837 (2011).Google Scholar
15.Francis, J.S.C. and Raj, R.: Flash-sinterforging of nanograin zirconia: field assisted sintering and superplasticity. J. Am. Ceram. Soc. 9, 19 (2011).Google Scholar
16.Cologna, M., Rashkova, B., and Raj, R.: Flash sintering of nanograin zirconia in <5 s at 850°C. J. Am. Ceram. Soc. 93, 35573559 (2010).CrossRefGoogle Scholar
17.Narayan, J.: New mechanism for electric-field assisted processing and flash sintering of materials. Scrip. Mater. 69, 107111 (2013). (Invited Viewpoint Paper).CrossRefGoogle Scholar
18.Narayan, J.: Grain growth model for electric-field assisted processing and flash sintering of materials. Scrip. Mater. 68, 785788 (2013).CrossRefGoogle Scholar
19.Mal, S., Yang, T-H., Gupta, P., Prater, J.T., and Narayan, J.: Thin film epitaxy and magnetic properties of STO/TiN buffered ZnO on Si (001) substrates. Acta Mater. 59, 25262534 (2011).Google Scholar
20.Gupta, P., Dutta, T., Mal, S., and Narayan, J.: Controlled p-type to n-type conductivity transformation in NiO thin films by ultraviolet-laser irradiation. J. Appl. Phys. 111, 013706-1-7 (2012).Google Scholar
21.Narayan, J.: Physical properties of a〈100〉 dislocations in magnesium oxide. J. Appl. Phys. 57, 27032708 (1985).Google Scholar
22.Narayan, J. and Holland, O.W.: Characteristics of ion implantation damage and annealing phenomena in semiconductors. J. Electrochem. Soc. 131, 26512662 (1984).Google Scholar
23.Narayan, J., Chen, Y., and Moon, R.M.: Nickel colloids in reduced nickel-doped magnesium oxide. Phys. Rev. Lett. 46, 14911494 (1981).CrossRefGoogle Scholar
24.Hirth, J.P. and Loathe, J.: Theory of Dislocations (McGraw–Hill, New York, NY, 2002).Google Scholar
25.White, C.W., Narayan, J., and Young, R.T.: Laser annealing of ion implanted semiconductors. Science 204, 461468 (1979).Google Scholar