31 Influence of Annealing in Vacuum on Dispersion Kinetics of Titanium. . .
497
31.4 Conclusions
It was found that fragmentation of 100 nm thick titanium nanofilms deposited onto
leucosapphire and zirconium dioxide surfaces is characterized by approximately the
same course: during short-time annealing (2–5 min) at 1400
◦ C, they are still almost
continuous; with increase of annealing time at this temperature film, disintegration
process is intensified although the film fragments cover more than 70% of the
substrate surface even after a 20-min exposition; and, thus, under these conditions,
the film is quite suitable for use in high-temperature brazing of these oxides. With
increase of the annealing temperature up to 1600
◦ C, the film fragmentation rate is
growing rapidly. The film disintegrates completely after a 10-min exposition at this
temperature; therefore, it is not suitable for brazing.
During the study of kinetics of dispersion of zirconium nanofilms 100 nm thick
at the surface of leucosapphire and single crystals of zirconium dioxide, it was
determined that, up to 1400
◦ C, with short-term annealing (2–5 min), the film is
still practically continuous.
Besides, it was found that the process of dispersion of zirconium nanofilms at
the surface of leucosapphire and zirconium dioxide is intensified with increase of
the annealing time at 1400
◦ C, but, even after a 20-min annealing, films were still
covering a significant part of the surface of oxides. Approximately the same results
were obtained for annealing of films at both oxides’ surface at 1500
◦ C which makes
it possible to use zirconium coatings on these materials for further soldering of them
at temperatures up to 1500
◦ C. With annealing temperature increase up to 1600
◦ C,
the films begin to disperse intensively from the first minutes of annealing, and this
dispersion process is rapidly activated with an increase of the annealing time, which
makes it impossible to solder these oxides at the temperature.
Thus, using all the obtained data in graphic representation, it becomes possible
to find the necessary parameters (temperature and time) of the soldering process for
the studied nonmetallic materials metallized with zirconium nanofilms.
References
1. Hafakeyama F, Suganuma K (1986) Solid-state bonding of alumina to austenitic stainless steel.
J Mater Sci 21(7):2455
2. Naydich YV, Gab II, Kostyuk BD, Stetsyuk TV, Kurkova DI, Dukarov SV (2007) Investigation
of the ceramic materials connection processes (soldering) using metal nanofilms. J Rep Natl
Acad Sci Ukr 35:97 (in Ukranian)
3. Naydich YV, Gab II, Kostyuk BD, Stetsyuk TV, Kurkova DI, Dukarov SV, Kulikovskyy VY,
Onoprienko AA (2005) Effect of the thickness of metal nanofilms deposited on oxide and
carbide materials for their subsequent welding and soldering, on the structural and capillary
properties of films and on the strength of welded and welded joints. Adheziya Rasplavov i
Paika Materialov 38:69 (in Ukranian)
497
31.4 Conclusions
It was found that fragmentation of 100 nm thick titanium nanofilms deposited onto
leucosapphire and zirconium dioxide surfaces is characterized by approximately the
same course: during short-time annealing (2–5 min) at 1400
◦ C, they are still almost
continuous; with increase of annealing time at this temperature film, disintegration
process is intensified although the film fragments cover more than 70% of the
substrate surface even after a 20-min exposition; and, thus, under these conditions,
the film is quite suitable for use in high-temperature brazing of these oxides. With
increase of the annealing temperature up to 1600
◦ C, the film fragmentation rate is
growing rapidly. The film disintegrates completely after a 10-min exposition at this
temperature; therefore, it is not suitable for brazing.
During the study of kinetics of dispersion of zirconium nanofilms 100 nm thick
at the surface of leucosapphire and single crystals of zirconium dioxide, it was
determined that, up to 1400
◦ C, with short-term annealing (2–5 min), the film is
still practically continuous.
Besides, it was found that the process of dispersion of zirconium nanofilms at
the surface of leucosapphire and zirconium dioxide is intensified with increase of
the annealing time at 1400
◦ C, but, even after a 20-min annealing, films were still
covering a significant part of the surface of oxides. Approximately the same results
were obtained for annealing of films at both oxides’ surface at 1500
◦ C which makes
it possible to use zirconium coatings on these materials for further soldering of them
at temperatures up to 1500
◦ C. With annealing temperature increase up to 1600
◦ C,
the films begin to disperse intensively from the first minutes of annealing, and this
dispersion process is rapidly activated with an increase of the annealing time, which
makes it impossible to solder these oxides at the temperature.
Thus, using all the obtained data in graphic representation, it becomes possible
to find the necessary parameters (temperature and time) of the soldering process for
the studied nonmetallic materials metallized with zirconium nanofilms.
References
1. Hafakeyama F, Suganuma K (1986) Solid-state bonding of alumina to austenitic stainless steel.
J Mater Sci 21(7):2455
2. Naydich YV, Gab II, Kostyuk BD, Stetsyuk TV, Kurkova DI, Dukarov SV (2007) Investigation
of the ceramic materials connection processes (soldering) using metal nanofilms. J Rep Natl
Acad Sci Ukr 35:97 (in Ukranian)
3. Naydich YV, Gab II, Kostyuk BD, Stetsyuk TV, Kurkova DI, Dukarov SV, Kulikovskyy VY,
Onoprienko AA (2005) Effect of the thickness of metal nanofilms deposited on oxide and
carbide materials for their subsequent welding and soldering, on the structural and capillary
properties of films and on the strength of welded and welded joints. Adheziya Rasplavov i
Paika Materialov 38:69 (in Ukranian)