The Experts below are selected from a list of 318 Experts worldwide ranked by ideXlab platform
Kiyoshi Nogi - One of the best experts on this subject based on the ideXlab platform.
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Effect of temperature and surface roughness on the wettability of boron nitride by molten Al
Journal of Materials Science, 2007Co-Authors: Ping Shen, Hidetoshi Fujii, Kiyoshi NogiAbstract:Reactive wetting of hexagonal BN by molten Al at 1073–1273 K was studied using an improved Sessile Drop Method. The temperature and substrate surface roughness have a remarkable effect on the wetting behavior. Reasons for the large discrepancy in the final contact angles reported in the literature were addressed.
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surface tension of molten silicon measured by microgravity oscillating Drop Method and improved Sessile Drop Method
Acta Materialia, 2006Co-Authors: Hidetoshi Fujii, Taihei Matsumoto, Shun Izutani, Shoji Kiguchi, Kiyoshi NogiAbstract:Abstract The surface tension of molten silicon was measured using both the oscillating Drop Method and an improved Sessile Drop Method. The oscillating Drop Method was used under microgravity conditions. The purity of the silicon sample was 9N. The atmosphere was Ar–3% H2 gas purified using platinum asbestos and magnesium perchlorate. The result measured using the oscillating Drop Method agrees very well with that measured using the Sessile Drop Method, and is expressed by the following equation: γ = 733 − 0.062(T − 1687), where γ is the surface tension (mN/m) and T is the temperature (K). The standard deviation of the scatter of the values obtained by the oscillating Drop Method is less than 1% which is smaller than that obtained by the Sessile Drop Method. In addition, the surface tension can be measured over a wider temperature range including the undercooled state using the oscillating Drop Method. Accordingly, a much more accurate temperature dependence is obtained.
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Measurement of contact angle and work of adhesion at high temperature
Journal of Materials Science, 2005Co-Authors: Nicolas Eustathopoulos, Natalia Sobczak, Alberto Passerone, Kiyoshi NogiAbstract:A critical review is given of the present state of knowledge and future perspectives in high-temperature contact angle measurement. Experimental results obtained by the different versions of the Sessile Drop Method and by various procedures are given in order to illustrate the two main sources of scatter in wettability data, the first being related to the quality of the substrates and the second to control of the furnace atmosphere.
Andrea C Santomaso - One of the best experts on this subject based on the ideXlab platform.
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wettability of mineral and metallic powders applicability and limitations of Sessile Drop Method and washburn s technique
Powder Technology, 2012Co-Authors: Laura Susana, Filippo Campaci, Andrea C SantomasoAbstract:Abstract Characterization of powder wettability is a prerequisite to the understanding of many processes of industrial relevance such as agglomeration which spans from pharmaceutical and food applications to metallurgical ones. The choice of the wetting fluid is crucial: liquid must wet the powder in order for agglomeration to be successful. Different Methods for wettability assessment of powders were reported in the literature, however the Sessile Drop Method and capillary rise test remain among the most widely employed because they are easy to perform and inexpensive. In this paper, the application and limitations of Sessile Drop Method and capillary rise test on mineral and metallic surface were discussed. This work provides a collection of wettability measurements using several powders and binders which are involved in the manufacturing process of welding wires. Moreover a new reference liquid for the calibration of capillary rise Method was proposed.
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Wettability of mineral and metallic powders: Applicability and limitations of Sessile Drop Method and Washburn's technique
Powder Technology, 2012Co-Authors: Laura Susana, Filippo Campaci, Andrea C SantomasoAbstract:Characterization of powder wettability is a prerequisite to the understanding of many processes of industrial relevance such as agglomeration which spans from pharmaceutical and food applications to metallurgical ones. The choice of the wetting fluid is crucial: liquid must wet the powder in order for agglomeration to be successful. Different Methods for wettability assessment of powders were reported in the literature, however the Sessile Drop Method and capillary rise test remain among the most widely employed because they are easy to perform and inexpensive. In this paper, the application and limitations of Sessile Drop Method and capillary rise test on mineral and metallic surface were discussed. This work provides a collection of wettability measurements using several powders and binders which are involved in the manufacturing process of welding wires. Moreover a new reference liquid for the calibration of capillary rise Method was proposed. © 2012 Elsevier B.V.
Wanlin Wang - One of the best experts on this subject based on the ideXlab platform.
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Study on the Interaction Process Between Mold Flux and TiN/TiO 2 by Sessile Drop Method
TMS 2020 149th Annual Meeting & Exhibition Supplemental Proceedings, 2020Co-Authors: Lejun Zhou, Wanlin WangAbstract:The interfacial property is the key factor to determine the solubility and absorption of solid inclusions by mold flux in the continuous casting process. In this study, the interfacial interactions between slag Droplet and TiO2, TiN substrates were investigated by Sessile Drop Method. By processing the image of the experimental process, it could be found that the molten flux has a good wettability for both TiO2 and TiN substrates. A large number of bubbles were observed on the surface of the Droplet during the reaction between the Droplet and the TiN substrate, which indicated that TiN was oxidized by liquid mold flux. Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) were used to observe the reaction interface of the sample after the Sessile Drop test, and the results showed that the final products of interfacial interaction between the slag Droplet and TiO2 substrate are perovskites and that for TiN substrate are also perovskites.
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study on the interaction process between mold flux and tin tio 2 by Sessile Drop Method
2020Co-Authors: Lejun Zhou, Wanlin WangAbstract:The interfacial property is the key factor to determine the solubility and absorption of solid inclusions by mold flux in the continuous casting process. In this study, the interfacial interactions between slag Droplet and TiO2, TiN substrates were investigated by Sessile Drop Method. By processing the image of the experimental process, it could be found that the molten flux has a good wettability for both TiO2 and TiN substrates. A large number of bubbles were observed on the surface of the Droplet during the reaction between the Droplet and the TiN substrate, which indicated that TiN was oxidized by liquid mold flux. Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) were used to observe the reaction interface of the sample after the Sessile Drop test, and the results showed that the final products of interfacial interaction between the slag Droplet and TiO2 substrate are perovskites and that for TiN substrate are also perovskites.
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Effect of Al 2 O 3 /SiO 2 and CaO/Al 2 O 3 ratios on wettability and structure of CaO–SiO 2 –Al 2 O 3 -based mold flux system
Journal of Iron and Steel Research International, 2019Co-Authors: Wanlin Wang, Lejun Zhou, Lei Zhang, Huan LiAbstract:The effect of Al2O3/SiO2 and CaO/Al2O3 ratios on the molten structure of CaO–SiO2–Al2O3-based mold flux system was analyzed by Fourier transform infrared spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. Also, the variation in the wettability between the mold flux system and an interstitial free (IF) steel substrate was investigated using the Sessile Drop Method. The results indicate that the contact angle and interfacial tension between the molten slag and solid steel increase slightly with the increase in the Al2O3/SiO2 ratio, while they decrease with the increase in the CaO/Al2O3 ratio. The network structure for the designed mold flux system changes gradually from silicate to aluminosilicate and aluminate with the increase in the Al2O3/SiO2 ratio, and the network is simplified with the increase in the CaO/Al2O3 ratio. Besides, combining the results of Sessile Drop Method and melt structure analyses, it suggests that the variation in interfacial properties of mold flux/IF steel substrate is mainly caused by the change in melt structure, especially the variation in free oxygen ions (O2−) and non-bridged oxygen (O−) at the interface.
Robin W Hughes - One of the best experts on this subject based on the ideXlab platform.
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slag density and surface tension measurements by the constrained Sessile Drop Method
Fuel, 2017Co-Authors: Marc A Duchesne, Robin W HughesAbstract:Abstract Density and surface tension of slag are important properties for mineral processing, metal processing, slagging combustion and slagging gasification. In the case of slagging gasification, slag properties will impact the efficiency, reliability, maintenance cost and environmental performance of the process. There are several Methods to determine the density and surface tension of slags. A commonly used technique is the Sessile Drop technique since it allows determination of both the density and surface tension, and can be performed at high temperatures in controlled gas atmospheres. This technique usually requires substrates that provide high contact angles with the samples for accurate results. To circumvent this issue, constrained Sessile Drops can be used. The limitations and accuracy of the constrained Sessile Drop technique for slag density and surface tension measurements were evaluated by a series of tests and phase equilibria predictions. Although molybdenum and alumina substrates provide lower contact angles than graphite substrates with the synthetic coal and petroleum coke slags tested, they interact less with the slags and alumina allows for measurements in both oxidizing and reducing conditions. Use of constraining 8 mm diameter molybdenum and alumina substrates resulted in greater precision than use of larger constraining and non-constraining substrates. The density of the synthetic coal slag studied is in the range of ∼2.4 g/cm 3 for the temperature range of 1200–1600 °C, in both oxidizing and reducing conditions. Based on measurements with a molybdenum substrate, its surface tension is ∼420 mJ/m 2 for the same temperature range. Measurements with alumina substrates, in both oxidizing and reducing conditions, yielded similar results above 1450 °C, but higher surface tension was observed at lower temperatures. Measurements with real coal slag provided similar results to measurements with synthetic coal slag. In the temperature range of 1530–1630 °C, the synthetic petroleum coke slag has a density of ∼2.4 g/cm 3 . Its surface tension is ∼360 mJ/m 2 in oxidizing conditions and ∼460 mJ/m 2 in reducing conditions. The surface tension difference is likely due to different phase equilibria with oxidizing and reducing environments, and may be impacted by the presence of solids in reducing conditions.
V Nagacevschi - One of the best experts on this subject based on the ideXlab platform.
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on the measurement of surface tension for liquid fesib glass forming alloys by Sessile Drop Method
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 1997Co-Authors: Horia Chiriac, M Tomut, C Naum, F Necula, V NagacevschiAbstract:Abstract An experimental set-up for measuring the surface tension and contact angles, of liquid metals and alloys at high temperatures is presented. The apparatus is based on Sessile Drop Method and uses a charge coupled device (CCD) camera to take the Drop profile. Using this Method, the surface tension of liquid Fe73B13Si9, alloy and it's dependence on temperature has been investigated. Contact angles of this liquid alloy on quartz, alumina and boron nitride have also been determined using the presented apparatus.
