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31.
A large quantity of gold (approximately 10 tonnes yearly) is consumed, all over the world, just to decorate ceramic and glassware.
Due to their advanced chemical stability gold films are used for different high technology applications. The technologies
for obtaining the best “liquid bright gold” were intensively studied, but the quality of the decor coatings (films) were empirically
assessed. We proposed a scientific investigation of the characteristics of gold films, deposited on ceramic substrates, from
“liquid bright golds”. The composition of the film has been determined by EDS (Energy Dispersive X-ray Spectrometry). The
distribution of the elements was determined at the surface of the film and in cross-section. The surface distribution of the
elements was uniform. The diffusion process of the film into substrate and the migration of the substrate elements at the
interface region and into the film have been highlighted. 相似文献
32.
N. Markocsan P. Nylén J. Wigren X.-H. Li A. Tricoire 《Journal of Thermal Spray Technology》2009,18(2):201-208
Thermal barrier coating (TBCs) systems made of plasma sprayed zirconia are commonly used in gas turbine engines to lower metal
components surface temperature and allow higher combustion temperature that results in higher fuel efficiency and environmentally
cleaner emissions. Low thermal conductivity and long service life are the most important properties of these coatings. The
objective of this work was to study the influence of a long-term heat treatment (i.e., 1200 °C/2000 h) on different characteristics
of atmospheric plasma sprayed TBCs. Two zirconia feedstock materials were evaluated, namely, yttria partially stabilized zirconia
and dysprosia partially stabilized zirconia. Several spray conditions were designed and employed to achieve different coating
morphologies. Microstructure analyses revealed that the coating microstructure was significantly dependent on both operating
conditions and heat treatment conditions. Significant changes in coatings porosity occurred during heat treatment. The lowest
thermal conductivity was reached with the dysprosia partially stabilized zirconia material. Heat treatment affected TBCs adhesion
strength as well. 相似文献
33.
Kim KH Moldovan N Ke C Espinosa HD Xiao X Carlisle JA Auciello O 《Small (Weinheim an der Bergstrasse, Germany)》2005,1(8-9):866-874
A hard, low-wear probe for contact-mode writing techniques, such as dip-pen nanolithography (DPN), was fabricated using ultrananocrystalline diamond (UNCD). Molding within anisotropically etched and oxidized pyramidal pits in silicon was used to obtain diamond tips with radii down to 30 nm through growth of UNCD films followed by selective etching of the silicon template substrate. The probes were monolithically integrated with diamond cantilevers and subsequently integrated into a chip body obtained by metal electroforming. The probes were characterized in terms of their mechanical properties, wear, and atomic force microscopy imaging capabilities. The developed probes performed exceptionally well in DPN molecular writing/imaging mode. Furthermore, the integration of UNCD films with appropriate substrates and the use of directed microfabrication techniques are particularly suitable for fabrication of one- and two-dimensional arrays of probes that can be used for massive parallel fabrication of nanostructures by the DPN method. 相似文献
34.
The laser performances of the 1.06 microm (4)F(3/2) --> (4)I(11/2) four-level transition and of the 0.9 microm (4)F(3/2) --> I(9/2)4 quasi-three-level transition were investigated using multipass pumped Nd-based media in thin-disk geometry. When pumping at 0.81 microm into the (4)F(5/2) level, continuous-wave laser operation was obtained with powers in excess of 10 W at 1.06 microm, in the multiwatt region at 0.91 microm in Nd:YVO(4) and Nd:GdVO(4), and at 0.95 microm in Nd:YAG. Intracavity frequency-doubled Nd:YVO(4) thin-disk lasers with output powers of 6.4 W at 532 nm and of 1.6 W at 457 nm were realized at this pumping wavelength. The pumping at 0.88 microm, which is directed into the (4)F(3/2) emitting level, was also employed, and Nd:YVO(4) and Nd:GdVO(4) thin-disk lasers with ~9 W output power at 1.06 microm and visible laser radiation at 0.53 microm with output power in excess of 4 W were realized. Frequency-doubled Nd:vanadate thin-disk lasers with deep blue emission at 0.46 microm were obtained under pumping directly into the (4)F(3/2) emitting level. 相似文献
35.
Satyapal Mahade Nicholas Curry Stefan Björklund Nicolaie Markocsan Per Nylén Robert Vaßen 《Journal of Thermal Spray Technology》2017,26(1-2):108-115
7-8 wt.% Yttria-stabilized zirconia (YSZ) is the standard thermal barrier coating (TBC) material used by the gas turbines industry due to its excellent thermal and thermo-mechanical properties up to 1200 °C. The need for improvement in gas turbine efficiency has led to an increase in the turbine inlet gas temperature. However, above 1200 °C, YSZ has issues such as poor sintering resistance, poor phase stability and susceptibility to calcium magnesium alumino silicates (CMAS) degradation. Gadolinium zirconate (GZ) is considered as one of the promising top coat candidates for TBC applications at high temperatures (>1200 °C) due to its low thermal conductivity, good sintering resistance and CMAS attack resistance. Single-layer 8YSZ, double-layer GZ/YSZ and triple-layer GZdense/GZ/YSZ TBCs were deposited by suspension plasma spray (SPS) process. Microstructural analysis was carried out by scanning electron microscopy (SEM). A columnar microstructure was observed in the single-, double- and triple-layer TBCs. Phase analysis of the as-sprayed TBCs was carried out using XRD (x-ray diffraction) where a tetragonal prime phase of zirconia in the single-layer YSZ TBC and a cubic defect fluorite phase of GZ in the double and triple-layer TBCs was observed. Porosity measurements of the as-sprayed TBCs were made by water intrusion method and image analysis method. The as-sprayed GZ-based multi-layered TBCs were subjected to erosion test at room temperature, and their erosion resistance was compared with single-layer 8YSZ. It was shown that the erosion resistance of 8YSZ single-layer TBC was higher than GZ-based multi-layered TBCs. Among the multi-layered TBCs, triple-layer TBC was slightly better than double layer in terms of erosion resistance. The eroded TBCs were cold-mounted and analyzed by SEM. 相似文献
36.
Armelle Vardelle Christian Moreau Jun Akedo Hossein Ashrafizadeh Christopher C. Berndt Jörg Oberste Berghaus Maher Boulos Jeffrey Brogan Athanasios C. Bourtsalas Ali Dolatabadi Mitchell Dorfman Timothy J. Eden Pierre Fauchais Gary Fisher Frank Gaertner Malko Gindrat Rudolf Henne Margaret Hyland Eric Irissou Bertrand Jodoin Eric H. Jordan Khiam Aik Khor Andreas Killinger Yuk-Chiu Lau Chang-Jiu Li Li Li Jon Longtin Nicolaie Markocsan Patrick J. Masset Jiri Matejicek Georg Mauer André McDonald Javad Mostaghimi Sanjay Sampath Günter Schiller Kentaro Shinoda Mark F. Smith Asif Ansar Syed Nickolas J. Themelis Filofteia-Laura Toma Juan Pablo Trelles Robert Vassen Petri Vuoristo 《Journal of Thermal Spray Technology》2017,26(5):985-986