- Fabrication of Ultra Fine Grained Molybdenum and Mechanical Properties
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Se-Hoon Kim, Young-Ik Seo, Dae-Gun Kim, Myung-Jin Suk, Young-Do Kim
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J Korean Powder Metall Inst. 2010;17(3):235-241.
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DOI: https://doi.org/10.4150/KPMI.2010.17.3.235
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 Abstract
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- Mo nanopowder was synthesized by ball-milling and subsequent hydrogen-reduction of MoO_3 powder. To fabricate ultra fine grained molybdenum, two-step sintering and spark plasma sintering process were employed. The grain size of specimen by two-step sintering and spark plasma sintering was around 0.6;µm and 0.4;µm, respectively. Mechanical properties of ultra fine grained Mo with relative density of above 90% were significantly improved at room and high temperatures comparing to commercial bulk Mo of 99% relative density. This result was mainly explained by the grain size refinement due to diffusion-controlled sintering.
- The Formation of Hybridized Porous Structure of Al Alloy by Alkali Surface Modification
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Young-Ik Seo, Young-Moon Kim, Young-Jung Lee, Dae-Gun Kim, Kyu-Hwan Lee, Young-Do Kim
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J Korean Powder Metall Inst. 2009;16(1):22-27.
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DOI: https://doi.org/10.4150/KPMI.2009.16.1.022
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Abstract
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- To improve the filtration efficiency of porous materials used in filters, an extensive specific surface area is required to serve as a site for adsorption of impurities. In this paper, a method for creating a hybridized porous alloy using a powder metallurgical technique to build macropores in an Al-4 wt.% Cu alloy and subsequent surface modification for a microporous surface with a considerably increased specific surface area is suggested. The macropore structure was controlled by granulation, compacting pressure, and sintering; the micropore structure was obtained by a surface modification using a dilute NaOH solution. The specific surface area of surface-modified specimen increased about 10 times compare to as-sintered specimen that comprised of the macropore structure. Also, the surface-modified specimens showed a remarkable increase in micropores larger than 10 nm. Such a hybridized porous structure has potential for application in water and air purification filters, as well as membrane pre-treatment and catalysis.
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Citations
Citations to this article as recorded by  - Development of Vacuum Thin-Film-Forming Mold using Porous Aluminum
Hyung-Sun Kang, Sunghyun Lee
Journal of the Korean Society of Manufacturing Technology Engineers.2020; 29(6): 435. CrossRef - Phosphorus removal from wastewater by ionic exchange using a surface-modified Al alloy filter
Young Ik Seo, Ki Ho Hong, Se Hoon Kim, Duk Chang, Kyu Hwan Lee, Young Do Kim
Journal of Industrial and Engineering Chemistry.2013; 19(3): 744. CrossRef
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