Page 261 - Book Hosokawa Nanoparticle Technology Handbook

FUNDAMENTALS CH. 4 CONTROL OF NANOSTRUCTURE OF MATERIALS
4.5.4.3 FSP and formation of surface partial composite [11] H. Fujii, R. Ueji, Y. Takada, H. Kitahara, N. Tsuji,
Although FSW was initially a technology developed K. Nakata and K. Nogi: Mater. Trans., 47, 239–242
as a joining method of metals, a field called friction (2006).
stir process (FSP) has spread, since it is possible to [12] R.S. Mishra, M.W. Mahoney, S.X. Mcfadden,
obtain a refined microstructure and to partially N.A. Mara and A.K. Mukherjee: Scripta Mater., 42,
strengthen a material using this technique [12–17]. 163–168 (1999).
Furthermore, it has recently become clear that the [13] H.J. Liu, H. Fujii and K. Nogi: Mater. Sci. Tech., 20,
grains are further refined by dispersing small parti- 399–402 (2004).
cles such as ceramic particles [18, 19], carbon nan- [14] Z.Y. Ma, R.S. Mishra and M.W. Mahoney: Scripta
otubes [20], and C [21] into metal.
60
Morisada et al. [19–21] engraved the sample sur- Mater., 50, 931–935 (2004).
face (AZ31) with a slot having a 1 mm width and 2 [15] M.L. Santella, T. Engstron, D. Storjohann and
mm depth, filled it with carbon nanotubes, C 60 or T.Y. Pan: Scripta Mater., 53, 201–206 (2005).
ceramic particles, and then performed FSP on the [16] I. Charit, R.S. Mishra: Acta Mater., 53, 4211–4223
plate, as nanostructures, such as carbon nanotubes, (2005).
cannot easily be dispersed in a metal by a liquid-phase [17] J.Q. Su, T.W. Nelson and C.J. Sterling: Mater. Sci.
method. Because the distribution of these particles Eng. A, 405, 277–286 (2005).
can restrict the grain growth, the crystal grain is much [18] R.S. Mishra, Z.Y. Ma and I. Charit: Mater. Sci. Eng.
smaller than that in the simply FSPed sample, as A, 341, 307–310, (2003).
shown in Fig. 4.5.24, which can significantly improve [19] Y. Morisada, H. Fujii, T. Nagaoka and M. Fukuzumi:
the hardness from 41 Hv of the base material to 78
Hv. When only FSP is performed, the hardness Mater. Sci. Eng. A., 433, 50–54 (2006).
increases only to 55 Hv. [20] Y. Morisada, H. Fujii, T. Nagaoka and M. Fukuzumi:
Because the thermal stability of the FSPed part is Mater. Sci. Eng. A., 419 344–348 (2006).
lower due to the introduction of a distortion into the [21] Y. Morisada, H. Fujii, T. Nagaoka and M. Fukuzumi:
metal, the crystal grain can become larger than that of Scripta, 55, 1067–1070 (2006).
the base material due to remarkable grain growth
when the temperature is raised after the FSP as shown
in Fig. 4.5.25. However, when SiC particles are dis- 4.5.5 Aerosol deposition method for nanostructuring
tributed, the grain growth is restricted and the thermal of crystal layer and its applications
stability is significantly improved.
Within the field of nanotechnology research, the
study of nanoparticles has become an active research
References topic. In addition, fabrication technologies to realize
nanostructure materials and to use nanoparticles for
[1] H. Okamura, K. Aota and M. Ezumi: J. Jpn. Inst. thin-film coatings are also being actively studied.
Light Met., 50, 166–171 (2000). Although thermal spray-coating technology using
[2] G. Campbell, T. Stotler: Weld. J., 78, 45–47 (1999). powders as a source material has been used for a long
[3] M.R. Johnsen: Weld. J., 78, 35–39 (1999). time, its applications have been limited because the
high temperatures needed do not permit the forma-
[4] K.E. Knipstron, B. Pekkari: Weld. J., 76, 55–57
tion of films with acceptable electrical and mechani-
(1997).
cal properties. Many of the problems with existing
[5] C.J. Dawes, W.M. Thomas: Weld. J., 75, 41–45 (1996).
coating techniques have been solved, however, by
[6] W.M. Thomas, E.D. Nicholas, J.C. Needhan, M.G.
impacting dry powders with substrates to be coated at
Murch, P. Temple-Smith and C.J. Dawes: impact velocities of several hundreds of meters per
International Patent Application PCT/GB92/02203 second. It is thought that reaction zones with high
and GB Patent Application 9125978.8, UK Patent temperature and high pressure are formed when par-
Office, London, December 6, 1991. ticles release kinetic energy during high-energy
[7] C.J. Dawes, W.M. Thomas: Weld. J., 53, 41 (1996). impacts, permitting them to collide and bond firmly
[8] Japan Welding Society: Friction Stir Welding, Sanpo with a substrate. The advantage of such a process is
that nanostructured layers can be formed at lower
Publication, Tokyo (2006).
temperatures than other spray-coating techniques,
[9] H. Fujii, R. Ueji, Y. Takada, H. Kitahara, N. Tsuji,
producing films with superior electrical and
K. Nakata and K. Nogi: Mater. Trans., 47, 239–242
mechanical properties.
(2006).
This method is called the aerosol deposition
[10] O. Frigaard, O. Grong, B. Bjorneklett and O.T. Midling: method (AD). In this paper we explain the principle of
Proceedings of the Ist International Symposium on the AD method and its application to ceramic film
FSW, Thousand Oaks, USA, 14–16 June, 1999, formation for information/communication and energy
8-2CD-ROM. technology applications.
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