http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
단결정 초내열합금에서 평면형 포정응고에 미치는 액상유동의 영향
구지호 ( Jiho Gu ),성창훈 ( Changhoon Sung ),신종호 ( Jongho Shin ),서성문 ( Seongmoon Seo ),이재현 ( Jehyun Lee ) 대한금속재료학회(구 대한금속학회) 2016 대한금속·재료학회지 Vol.54 No.4
The γ/γ´ two-phase growth commonly observed at γ interdendritic regions in Ni-base superalloys is known to be the eutectic microstructure. However, it is still unclear whether this is due to a eutectic or peritectic reaction. Directional solidification experiments of the Ni-base superalloy CMSX-10 were performed at low solidification rates in order to induce the coupled growth of γ/γ´ phases and to investigate their growth behavior. The γ and γ´ phases were found to grow simultaneously, maintaining an isothermal interface. Directional solidification experiments in a thin tube (0.8 mm ID) suggest that convection enhances the formation of two phase peritectic growth with a planar interface and the γ/γ´ might be the couped peritectic.
Cha, Jiho,Han, Jung-Gu,Hwang, Jaeseong,Cho, Jaephil,Choi, Nam-Soon Elsevier 2017 Journal of Power Sources Vol.357 No.-
<P><B>Abstract</B></P> <P>Lithium difluoro(oxalato)borate (LiDFOB) with one oxalate moiety bonded to a central boron core was employed as a salt-type additive to enhance the interfacial stabilities of high-voltage Li-rich cathodes and graphite anodes. Our investigation revealed that the LiDFOB additive modified the surface film on the electrodes and effectively restrained degradation of the cycling performance of the electrodes. Investigation of the surface chemistries of the electrodes confirmed that LiDFOB produces a LiF-less surface film on the Li-rich cathode and a LiF-rich surface film on the graphite anode. Moreover, the use of 1% LiDFOB drastically improved the rate capabilities of Li-rich cathodes and graphite anodes. Within 100 cycles at a rate of C/2 at 25 °C, only 45.8% of the initial discharge capacity of a high-voltage Li-rich/graphite full cell was delivered in the baseline electrolyte, while the LiDFOB-containing electrolyte retained 82.7%.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Lithium difluoro(oxalato)borate (LiDFOB) is used as an electrolyte additive. </LI> <LI> LiDFOB affects both cathode and anode solid electrolyte interphase (SEI) formation. </LI> <LI> LiDFOB produces a semi-carbonate-based SEI on Li-rich cathodes. </LI> <LI> The LiDFOB-derived SEI on graphite anodes consists mostly of LiF. </LI> <LI> Excellent electrode performance is achieved with LiDFOB. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
Solidification and Segregation Behaviors in 6061 Aluminum Alloy
Heesik Seo,Jiho Gu,Kyungmi Park,정연길,이재현,정원섭 대한금속·재료학회 2013 METALS AND MATERIALS International Vol.19 No.3
The characteristics of a solid/liquid interface established during directional solidification were investigated in a 6061 aluminum alloy (Al6061 alloy) in which interface patterns, such as planar, cellular and dendritic,form in the mushy zone. Directional solidification experiments were carried out in alumina tubes with an inner diameter of 5 mm to obtain the different microstructures for varying growth rates under an imposed thermal gradient of 9.45 K/mm. As a consequence, primary arm spacing, secondary arm spacing and the length of primary arm were measured for steady-state growth conditions. Furthermore, the solute concentration profiles for the final solidification region were obtained using a SEM-EDS system in order to examine the segregation behaviors of alloying elements. Therefore, it was found that the degree of segregation in the Al6061 alloy was dependent on the growth rate under given solidification conditions, that is, the elemental segregation became more severe with increasing growth rate in the interdendritic region.
경계검출을 통한 가변적 윈도우 크기를 갖는 SAD정합기 설계
양승구(Seung-gu Yang),장지호(Jiho Chang),이정수(Jongsu Yi),김준성(JunSeong Kim) 대한전자공학회 2007 대한전자공학회 학술대회 Vol.2007 No.7
Stereo vision systems support various applications including robots and home networks by providing 3 dimensional environmental information. A regularity and a simplicity in the structure make SAD (Sum of Absolute Difference) correlation be popular for stereo vision implementation using reconfigurable hardware. In this paper, we investigated the accuracy of SAD correlator with adaptive window size through edge detection.
윈도우 크기와 변이도 축약에 따른 SAD 정합기의 정확도
양승구(Seung-gu Yang),장지호(Jiho Chang),이정수(Jongsu Yi),김준성(JunSeong Kim) 대한전자공학회 2006 대한전자공학회 학술대회 Vol.2006 No.11
Stereo vision systems support various applications including robots and home networks by providing 3 dimensional environmental information. A regularity and a simplicity in the structure make SAD (Sum of Absolute Difference) correlation be popular for stereo vision implementation using reconfigurable hardware. In this paper, we investigated the accuracy of SAD correlator with various window sizes and disparity abridgements.
Zhongping Que,Jiho Gu,Jongho Shin,정연길,Jehyun Lee 대한금속·재료학회 2014 METALS AND MATERIALS International Vol.20 No.1
Directional solidification experiments of a binary Ni-23at.%Al alloy were carried out to examine the effectsof growth velocity on the microstructure selection in the interdendritic region. Only the growth velocity waschanged from 5 µm/s to 60 µm/s under a given thermal gradient. As a result, the noticeable change in themicrostructure during solidification occurred between the γ dendrites. The γ interdendritic microstructure wasvaried as a function of growth velocity from rod γ-γ' coupled peritectic structure to planar γ' structure andthen to eutectic structures consisting of stable γ'-β eutectic and metastable γ-β‚ eutectic structures. Themicrostructure selected preferentially among the γ dendrites was considered by calculating the interfacetemperature of a phase growing into its parent melt. It is shown that the microstructure selection in the γinterdendritic region is determined by a phase or a structure kinetically leading at the highest interfacetemperature under a given growth condition.