환원.확산법에 의한 $Sm_{2}Fe_{17}N_{x}$ 계 희토류 영구자석의 제조에 관한 기초연구(제 1보) -$Sm_{2}Fe_{17}$금속간화합물 합금분말의 제조-

송창빈,조통래,Song, Chang-Bin,Choo, Tong-Rae 한국재료학회 1998 한국재료학회지 Vol.8 No.8

환원.확산법에 의해 $Sm_{2}Fe_{17}N_{x}$ 계 희토류 영구자석을 제조하기 위한 기초연구로서, 우선 $Sm_{2}Fe_{17}$ 금속간화합물의 제조를 위하여, 금속 Ca에 의한 $Sm_2O_3$의 환원반응과 Fe분말중에 Sm의 확산반응을 검토하였다. 그 결과 전자는 $1000^{\circ}C$이상의 고온의 경우에 매우 빠르게 완료되지만, 후자의 Fe분말의 중심까지 Sm의 확산반응의 완료(완전한 균질화조건)는 $1100^{\circ}C$에서 3h 정도의 R-D 반응이 필요하며, 이 확산반응이 전체반응에 있어서 율속단계임을 알았다. Sm-Fe 계의 금속간화합물들의 성장은$ 1000^{\circ}C$이하에서는 $SmFe_2$, $SmFe_3$,$Sm_{2}Fe_{17}$금속간화합물의 3개의 상이 관찰되었으나, $1100^{\circ}C$에서는 $Sm_{2}Fe_{17}$ 금속간화합물의 상만이 관찰되었다. 본 연구에서 얻어진 최종시료의 산소 및 Ca량은 각각 0.72wt% 및 0.11wt%이었다. As a basic study on the production of $Sm_{2}Fe_{17}N_{x}$ system rare earth permanent magnet by the reduction and diffusion(R- D) process, firstly the reduction reaction of $Sm_2O_3$ by metallic Ca and diffusion of Sm into Fe powder was investigated for the production the $Sm_{2}Fe_{17}$intermetallic compound. We concluded that the former case was very rapidly completed under the high temperature greater than 100$0^{\circ}C$ and the latter case of completion of diffusion reaction of Sm into the center of Fe powder(perfect homogenization condition) was required through 3h R- D reaction at 110$0^{\circ}C$ and identified as a rate determining step(RDS) on the whole reaction. Though $SmFe_2,SmFe_3$, and $Sm_{2}Fe_{17}$phases in the growth of phases of intermetallic compound in the Sm - Fe binary system were obseved below 100$0^{\circ}C$, but only $Sm_{2}Fe_{17}$phase was observed at lIOO$^{\circ}C$. Oxygen and Ca contents of the final sample in this work were 0.72wt% and O. 11 wt% respectively.

2중 코어 구조의 소화기용 친환경 탄자 제조 및 특성 분석

홍준희,장탁순,송창빈,강대화,Hong, Jun-Hee,Jang, Tak-Soon,Song, Chang-Bin,Kang, Dae-Wha 한국군사과학기술학회 2011 한국군사과학기술학회지 Vol.14 No.3

This paper focuses on the properties analysis of 9mm bullet dual structure core to substitute current lead core by environment-friendly combination of W-Cu-Ni system high density composite materials. So the four combination samples were made of dual core with the different center of gravity location backward or forward compare to that of lead type bullet, and we experimented about the performance of 9mm bullet dual structure core. In the experimental results, the outer shape of core of four environment friendly samples on the target maintain marginally, while the current lead core bullets are completely crushed after hitting the target. The penetration depth of environment friendly samples excel seven times to lead type bullet and the three out of four samples with forward adjusted center of gravity penetrate deep as twice as ones backward. The impact tolerance of all four samples satisfies military specification, however, more firing tests are required to improve reliability of scattering distribution.

친환경 소화기용 탄심 재료 및 2중 구조 설계 분석

홍준희,장탁순,송창빈,김병인,Hong, Jun-Hee,Jang, Tak-Soon,Song, Chang-Bin,Kim, Byung-In 한국군사과학기술학회 2011 한국군사과학기술학회지 Vol.14 No.2

This paper focuses on possibility to design and fabrication new combination of bullet core to substitute current toxic material of heavy metal such as lead by environment-friendly ones. The core is designed as dual structure to manipulate the core center of gravity easily by combining materials, which of basis is tungsten of low cost and easily acquired. Those combinations are W-M series such as W-Cu, W-Sn, W-Cu-Sn, and W-Cu-Ni to target the density of lead, $11.34g/cm^3$ through powder-metallurgy. Out of four, combination of W-Cu-Ni shows the highest compression density of 96% and is confirmed as the most suitable substitution for lead due to the excellent property of matter and sintering. All combination samples is simulated on the PRODAS software for designing and structure analysis by adjusting the center of gravity of dual core samples forward and backward. The simulations confirm the similarity of current bullet core with respect to properties of mass, aero dynamics, and flying stability.

금속 Ca증기에 의한 고체 Nd 금속의 탈산

최영진,김상욱,전병서,송창빈,오윤석,이영주,Choi, Yonug-Jin,Kim, Sang-Wuk,Jeon, Byung-Seo,Song, Chang-Bin,Oho, Yoon-Seok,Lee, Young-Joo 한국재료학회 2017 한국재료학회지 Vol.27 No.5

As a basic study for the removal of oxygen in solid Nd metal by metal Ca vapour, by using the thermodynamic data such as ${\Delta}G-T$ diagrams and Nd-O and Nd-Ca equilibrium diagrams, the amount of residual oxygen in solid Nd metal formed based on deoxidation reaction by Ca vapour, instead of by direct contact of solid Nd metal and Ca solution, was determined. Deoxidation experiments were carried out for solid Nd metal in a temperature range of $890{\sim}970^{\circ}C$ for 1h to 4h and content of addition Ca of 0.6~1.8 g (5~15 wt% of solid Nd metal). As a result, it was found that as deoxidation temperature increased, dissolved oxygen decreased. Especially, it was observed that a small amount of Nd-Ca alloy liquid was formed on the surface of the solid Nd metal sample deoxidized at $970^{\circ}C$ for approximately 1 hour. Also, it was found that if the content of addition Ca was 1.8 g (15 wt% of solid Nd metal) the amount of produced Nd-Ca alloy increased slightly. However, for the Nd sample with which the deoxidation reaction was performed at $930^{\circ}C$ for 4h with content of addition of Ca of 1.5 g (13 wt% of Nd metal), the residual oxygen was found to decreased to 12.00 ppm.

W-M(M=Cu, Sn, Ni)계 고밀도 복합재료 제조에 관한 기초연구(I)

장탁순,홍준희,이태행,구자명,송창빈,Jang, Tak-Soon,Hong, Jun-Hee,Lee, Tae-Haeng,Koo, Jar-Myung,Song, Chang-Bin 한국분말야금학회 2009 한국분말재료학회지 (KPMI) Vol.16 No.4

For the purpose of obtaining basic information on the development of lead-free materials, a high density composites (a) W-Cu, (b) W-Sn (c)W-Cu-Sn and (d) W-Cu-Ni were fabricated by the P/M method. The particle size of used metal powders were under 325 mesh, inner size of compaction mould was $\phi8$ mm, and compaction pressure was 400 MPa. A High density composite samples were sintered at a temperature between $140^{\circ}C$ and $1050^{\circ}C$ for 1 hour under Ar atmosphere. The microstructure, phase transformation and physical properties of the sintered samples were investigated. As the results, the highest relative density of 95.86% (10.87 g/$cm^3$) was obtained particularly in the sintered W-Cu-Sn ternary system sample sintered at 450 for 1hr. And, Rockwell hardness (HRB) of 70.0 was obtained in this system.

산화·환원법에 의한 폐텅스텐 스크랩의 재활용에 관한 기초연구

김상욱,윤지석,김태욱,조봉휘,김인호,김상무,송창빈,Kim, Sang-Uk,Yun, Ji-seok,Kim, Tae-Wook,Cho, Bong-Hwi,Kim, In-Ho,Kim, Sang-Mu,Song, Chang-Bin 한국분말야금학회 2017 한국분말재료학회지 (KPMI) Vol.24 No.1

This study is carried out to obtain basic data regarding oxidation and reduction reactions, originated on the recycling of waste tungsten hard scraps by oxidation and reduction processes. First, it is estimated that the theoretical Gibbs free energy for the formation reaction of $WO_2$ and $WO_3$ are calculated as ${\Delta}G_{1,000K}=-407.335kJ/mol$ and ${\Delta}G_{1,000K}=-585.679kJ/mol$, from the thermodynamics data reported by Ihsan Barin. In the experiments, the oxidation of pure tungsten rod by oxygen is carried out over a temperature range of $700-1,000^{\circ}C$ for 1 h, and it is possible to conclude that the oxidation reaction can be represented by a relatively linear relationship. Second, the reduction of $WO_2$ and $WO_3$ powder by hydrogen is also calculated from the same thermodynamics data, and it can be found that it was difficult for the reduction reaction to occur at $1,027^{\circ}C$, in the case of $WO_2$, but it can happen for temperatures higher than $1127^{\circ}C$. On the other hand, $WO_3$ reduction reaction occurs at the relatively low temperature of $827^{\circ}C$. Based on these results, the reduction experiments are carried out at a temperature range of $500-1,000^{\circ}C$ for 15 min to 4 h, in the case of $WO_3$ powder, and it is possible to conclude that the reduction at $900^{\circ}C$ for 2h is needed for a perfect reduction reaction.

IC 반도체 테스트 소켓용 전도성 니켈기(Ni-Based) 합금제조에 관한 연구

김인호(In-Ho Kim),김경식(Kyung-Sik Kim),이태행(Tae-Heng Lee),송창빈(Chang-Bin Song) 한국자기학회 2020 韓國磁氣學會誌 Vol.30 No.6

Recently, pure Ni powder, used as conductive powder material for semiconductor test sockets, has disadvantage of decreasing the life cycle of test sockets because of its low hardness (Hv = 100). This study was carried out composition design of the Ni-(0.1~30)wt%X binary alloys and the Ni-3wt%Fe-0.3wt%X ternary alloys, ingot manufacturing, heat treatment, polishing, microstructure observation and characteristic evaluation to develop new Fe-based Electric Conductivity alloy with excellent hardness to replace pure nickel powder. As a result, although the Ni-5wt%Co(Fe) binary alloys with Co and Fe elements is more conductive and magnetic than other alloys, in order to improve hardness, it was found that the adding B and C element is more effective. Meanwhile, it was found that the electrical resistance of alloys depended on Matthiessens rules and mixing rules, the magnetism of alloys is enhanced in proportion to the increase addition of Co and Fe elements. Furthermore, the hardness was found that the presence of solid solution (or intermetallic compound) according to the chemical composition of the alloy, and the precipitation hardening caused by heat treatment were combined.

메인 메모리 DBMS P^*TIME 기반 WAP 서버 구현

윤용식(Yong-Sik Yoon),노재윤(Jae-Yun No),송창빈(Chang-Bin Song),차상균(Sang-Kyun Cha) 한국정보과학회 2001 한국정보과학회 학술발표논문집 Vol.28 No.2Ⅰ

최근 개인 휴대폰의 대중화에 따라 기존의 유선 인터넷 환경과 휴대폰 서비스가 결합된 무선 인터넷 서비스가 각광을 받고 있다. 현재 웹을 기반으로 WAP 인터페이스를 제공하는 회사들은 디스크 기반 DBMS를 사용한다. 데이터의 전송 속도가 유선 상에 비해 떨어지고 회선이 불안정한 무선 인터넷의 특성상, 응답 시간이 느릴 경우 사용자는 서비스 이용에 큰 불편을 느낄 수밖에 없고, 이용상에 오류가 생길 가능성이 높아진다. 이에 비추어 볼 때 응답 시간을 기존의 유선 인터넷 서비스에 비해 더욱 중요한 요소로 작용한다. 디스크 기반 DBMS는 이와 같은 요구 조건을 만족하지 못한다. 그에 반해 구조가 간단하면서 높은 성능을 낼 수 있는 메인 메모리 DBMS는 무선 인터넷 서비스에 적합한 환경을 제공한다. 본 논문에서는 2세대 고성능 메인 메모리 DBMS인 P^*TIME을 이용하여 무선 인터넷 서버를 구현하고, 그 성능을 상용 DRDBMS인 Oracle을 이용했을 때의 성능과 비교 분석해 본다. WML, WML Script, JSP를 이용하여 PIMS 서비스를 구현해 본 결과, 동시 접속사 수가 늘어남에 따라 Oracle과 P^*TIME의 성능 차이는 더욱 크게 벌어져 동시 접속사 수가 50명일 경우 P^*TIME이 100배 이상의 성능을 보였다.

IC 반도체 테스트 소켓용 전도성 Fe-Cu-X계 합금 제조에 관한 연구

김인호(In-Ho Kim),전병서(Byung-Seo Jeon),이태행(Tae-Heng Lee),송창빈(Chang-Bin Song) 한국자기학회 2021 韓國磁氣學會誌 Vol.31 No.6

This study was carried out to develop a new alloy superior to pure nickel powder used as a conductive powder material for a semiconductor test socket. As such means, composition variation of Fe-(3~70)wt%Cu binary system and Fe-Cu-X (X = Ag, Co, Sn) ternary system alloy, ingot manufacturing, thermal treatment, polishing, microstructure observation, and physical properties (electrical resistance, magnetism and hardness) were investigated. As a result, some of Fe-Cu binary alloys and Fe-Cu-X ternary system alloy had better properties than pure Ni. For example, in the Fe-(3~70)wt%Cu binary system alloy, the Fe-50wt%Cu alloy had electrical resistance (ρ) = 6.8 × 10<SUP>-8</SUP> Ω·cm, magnetism (Bs) = 0.9 (T) and hardness (Hv) = 209.8, which were superior to pure Ni. One of those reasons was estimated to be due to an increase in the volume fraction on the Cu (S.S.). In addition, in the case of Fe-Cu-X ternary system alloys, particularly, it was confirmed that the addition of Ag, Co, and Sn elements has a slight effect of increasing electrical resistance, but the magnetism (Bs) decreased as expected.

아연처리법에 의한 폐초경합금의 재활용에 관한 기초연구

송창빈 공주대학교 생산기술연구소 2002 論文集 Vol.10 No.-

This study was carried out basic experiments mainly to investigate important zinc bath reaction mechanism, addition amount of Zn, reaction temperature and time etc., in recycling of waste cemented carbide by zinc process. As the result, although should be heated more than at 800℃. And this study was examined that it was suitable that apply heat more than at 900℃ for 1 hour after diffusion reaction in lower temperature than 800℃ for vapour and residual amount of zinc bath process.