플라즈마 질화법에 의한 SUS316L 스테인레스강의 표면경화에 관한 연구

박정환,김영홍,유용주 울산대학교 1994 공학연구논문집 Vol.25 No.2

본 연구는 SUS316L 스테인레스강을 이용하여 500℃∼600℃의 온도범위에서 NH₃가스의 유량을 0.5∼2.1ℓ/min로 변화시키고, 20∼110분 동안 플라즈마 질화처리하여, 강 표면에 생성된 경화층의 두께와 경도 및 조직을 조사하였다. 반응온도 550℃, NH₃가스의 유량 2.1ℓ/min에서 110분 동안 질화 하였을 경우 생성된 질화층의 두께는 약57㎛로 최대치를 나타내었다. 그리고 질화처리 한 시편을 XRD 분석한 결과 생성된 질화층은 CrN+r-Fe₄N+Fe₃N으로 구성되어 있는 화합물층 이었으며, 확산층은 생성되지 않았고, 생성된 질화층의 경도의 최고치는 약 Hv 1800 이었다. 플라즈마 질화법에 의한 SUS316L 스테인레스 강의 표면경화의 최적조건은 550℃, 2.1ℓ/min. NH₃가스, 110분이었다. A nitrided layer on SUS316L stainless steel by plasma nitrised for back ferrule in one parts of tube fitting has been studied. Specimen was nitrided over 500℃ to 650℃ reaction temperature range with 0.5 to 2.1 ℓ/min. NH₃gas flow rate for 20 to 110 min. The thickness of nitrided layer showed maximum value about 57㎛ at 550℃ reaction temperature and with 2.1ℓ/min. NH₃gas flow rate for 110 min. The result of XRD, nitrided layer was mainly composed of CrN+r-Fe₄N+Fe₃N, but not detected diffusion layer. And also, when NH₃gas flow rate 2.1ℓ/min. , the maximum hardness value of nitrided layer was revealed about Hv 1800 at 550-600℃ reaction temperature range. In this study, the optimum condition of nitrided on SUS316L stainless steel was observed at 550℃ reaction temperature and 2.1ℓ/min. , NH₃gas flow rate for 110 min.

공연예술 서비스업의 코로나-19 환경 대응 안전관리 전략

박영만 ( Park¸ Young-man ),유진주 ( You¸ Jin-zoo ) 한국융합과학회(구 한국시큐리티융합경영학회) 2020 한국융합과학회지 Vol.9 No.4

연구목적: 이 연구는 공연예술 서비스업과 공연장 경영에 있어서 포스트 코로나 시대 대응 방안과 미래를 전망을 탐색하여 공연예술 분야의 안전관리 전략을 제시하는데 목적을 두고 이루어졌다. 연구방법: 연구 목적의 효과적인 달성을 위하여 활용한 연구 방법은 문헌 고찰과 전문가 집단의 협의 이다. 연구 방법에 의해 규명한 연구 결과는 다음과 같다 결과: 첫째, 관람객의 건강 검증 온라인 플랫폼의 활용이다. 둘째, 독립적인 공연장 전문 건물에 공연 실행을 허가한다. 셋째, 공연장 건물 출입로 동선을 사전에 정하고 공지하여 건물 진입 전의 관리를 강화해야 한다. 넷째, 실제 공연장 방문자와 비방문 관람객 동반 관람 서비스를 개발한다. 결론: 첫쩨, 정부의 포스트 코로나 대응 경제 정책을 지속적으로 모니터링하고 유연한 대응 마련의 기구 또는 체계의 준비와 운영이 필요하다. 둘째 공연예술 문화 콘텐츠의 고급화 전략을 신속하게 이루어야 한다. 셋째, 언택트 및 온택트로 일컬어지는 비대면 콘텐츠 산업의 성장세에 대응하고 혁신에 노력해야 한다. Purpose: This study was conducted with the aim of presenting safety management strategies in the performing arts field by exploring the post-corona era response plan and future prospects in the performing arts service industry and performance hall management. Methods: The research method used to effectively achieve the research purpose is a review of the literature and consultation with a group of experts. The research results identified by the research method are as follows. Result: First, the use of an online platform to verify the health of visitors. Second, it is permitted to perform performances in buildings specializing in independent performance halls. Third, it is necessary to reinforce the management before entering the building by pre-determining and notifying the entrance route of the performance hall building. Fourth, we will develop a viewing service with visitors to the actual concert hall and non-visit visitors. Conclusion: First, it is necessary to continuously monitor the government's post-corona response economic policy and prepare and operate an organization or system for flexible response arrangements. Second, it is necessary to quickly implement a strategy for upgrading the performing arts and cultural contents. Third, it is necessary to respond to the growth trend of the non-face-to-face content industry, which is referred to as untact and on-tact, and strive for innovation.

동전해정제시 음극분극전위에 미치는 첨가제의 영향에 관한 연구

오기식,유용주,김영홍 울산대학교 1985 연구논문집 Vol.16 No.2

전해첨가제를 동전해액(황산동-황산)에 각각 단독으로 또는 복합적으로 첨가하여 음극분극전위를 측정함으로써 다음과 같은 결론을 얻었다. 1) 첨가량이 많아짐에 따라 아교와 글리신은 음극분극전위를 현저히 높이며, 아비톤-A는 약간 증가시키고, 티오요소는 소량 첨가할 경우 감소시키나 첨가량이 많아지면 상당히 상승시킨다. 그리고 Cl?은 음극분극전위에 영향을 거의 미치지 않는다. 2) 아교를 주 첨가제로하고 티오요소 및 아비톤-A를 첨가했을 때 티오요소와 아비톤-A는 분극전위에 거의 영향을 미치지 못하고 주로 아교가 영향을 미친다. 3) 아교 5mg/l, 티오요소 3mg/1, Cl? 20mg/l를 가한 전해액을 이용한 일반적인 전해정제로 2.5A/dm²의 고전류밀도에서 평활하고 치밀한 전착면을 얻을 수 있었으며, 불순물의 제거가 가능하고 부동태현상이 발생 하지 않았다. Cathodic polarization potentials during the ectrorefining of copper have been measured under various conditions of addition agents in the copper electrolyte (CuSO₄-H₂SO₄). The results obtained are as follows. 1) The cathode polarization potential is affected by the kind of addition agents and the amount of addition to the electrolyte. Glue and glycine show remarkable increasing effects on the polarization potential, Aviton-A has a little effect. However, thiourea causes the polarization potential to increase considerably at high concentration, but showing a decreasing effect at low concentration. Chlorine has little effect on the polarization potential. 2) In the case of using the electrolyte containing glue with Aviton-A and glue with thiourea as additives, thiourea and Aviton-A have little effect on the polarization potential, while glue shows remarkable effect. 3) The electrorefining was carried out successfully using the electrolyte added glue 5mg/l, thiourea 3mg/l, and chlorine 20,g/l, with the current thiourea 3mg/l, and chlorine 20mg/l, with the current density of 2.5A/dm² for 68hrs at the pilot plant. The surface of deposit copper was smooth and its thickness was uniform, showing the purity of 99.99( copper.

SCM435 구조용 합금강의플라즈마 질화에 미치는 전처리 ( Q / T ) 의 영향

임영필,박대철,이재식,유용주 ( Young Phil Lim,Dae Chul Park,Jae Sig Lee,Yong Zoo You ) 한국열처리공학회 1998 熱處理工學會誌 Vol.11 No.2

N/A The effects of pre-heat treatment(Q/T) on microstructure and hardness of SCM435 structural steel nitrided by micro-pulse plasma was investigated. The quenching and tempering temperatures for obtaining matrix hardness of SCM435 steel on range of HRC30 to HRC40 desired for machine parts were about 860℃ and 500℃ respectively. The case depth of SCM435 nitrided at 480℃ for 5 hours was independent of pre-heat treatment condition and was approximately 150㎛. However, hardness and compactness of nitrified layer on Q/T treated specimen were more heigher than annealed specimen. The case depth increased linearly with the increase of nitriding temperature, however, the hardness of nitrified layer decreased with the temperature. Phase mixture of γ` -phase(Fe₄N) and ε-phase(Fe₃N) were detected by XRD analysis in the nitrified layer formed at optimum nitriding condition, and only single γ`-phase was detected in the nitrified layer formed at higher nitriding temperature such as 540℃. The optimum nitriding temperature was approximately 480℃ which is lower than tempering temperature for preventing softening behavior of SCM435 matrix during nitriding process and the surface hardness of nitrified layer obtained by optimum preheat treatment condition was about Hv930

고감도 ZnO 박막센서의 수소가스 검출 특성 연구

공영민,이학민,허성보,김선광,유용주,김대일,Kong, Young-Min,Lee, Hak-Min,Huh, Sung-Bo,Kim, Sun-Kwang,You, Yong-Zoo,Kim, Dae-Il 한국재료학회 2010 한국재료학회지 Vol.20 No.12

ZnO thin films were prepared on a glass substrate by radio frequency (RF) magnetron sputtering without intentional substrate heating and then surfaces of the ZnO films were irradiated with intense electrons in vacuum condition to investigate the effect of electron bombardment on crystallization, surface roughness, morphology and hydrogen gas sensitivity. In XRD pattern, as deposited ZnO films show a higher ZnO (002) peak intensity. However, the peak intensity for ZnO (002) is decreased with increase of electron bombarding energy. Atomic force microscope images show that surface morphology is also dependent on electron bombarding energy. The surface roughness increases due to intense electron bombardment as high as 2.7 nm. The observed optical transmittance means that the films irradiated with intense electron beams at 900 eV show lower transmittance than the others due to their rough surfaces. In addition, ZnO films irradiated by the electron beam at 900 eV show higher hydrogen gas sensitivity than the films that were electron beam irradiated at 450 eV. From XRD pattern and atomic force microscope observations, it is supposed that intense electron bombardment promotes a rough surface due to the intense bombardments and increased gas sensitivity of ZnO films for hydrogen gas. These results suggest that ZnO films irradiated with intense electron beams are promising for practical high performance hydrogen gas sensors.

증착조건과 진공열처리 온도에 따른 ITO/PES 박막의 특성 연구

이재영,박지혜,김유성,천희곤,유용주,김대일,Lee, Jae-Young,Park, Ji-Hye,Kim, Yu-Sung,Chun, Hui-Gon,You, Yong-Zoo,Kim, Dae-Il 한국재료학회 2007 한국재료학회지 Vol.17 No.4

Transparent conducting indium tin oxide (ITO) films were deposited onto the Polyethersulfone (PES) substrate by using a magnetron sputter type negative metal ion source. In order to investigate the influence of cesium (Cs) partial pressure during deposition and annealing temperature on the optoelectrical properties of ITO/PES film the films were deposited under different Cs partial pressures and post deposition annealed under different annealing temperature from $100^{\circ}C$ to $170^{\circ}C$ for 20 min at $3\;{\times}\;10^{-1}$ Pa. Optoeleetrical properties of ITO films deposited without intentional substrate heating was influenced strongly by the Cs partial pressure and the Cs partial pressure of $1.5\;{\times}\;10^{-3}$ Pa was characterized as an optimal Cs flow condition. By increasing post-deposition vacuum annealing temperature both optical transmission in visible light region and electrical conductivity of ITO films were increased. Atomic force microscopy (AFM) micrographs showed that the surface roughness also varied with post-deposition vacuum annealing temperature.

RF 스퍼터와 전자빔 조사를 이용한 ITO/Au/ITO 가스센서 제조 및 특성 평가

허성보 ( Sung Bo Heo ),이학민 ( Hak Min Lee ),( Young Jin Lee ),김유성 ( Yu Sung Kim ),채주현 ( Ju Hyun Chae ),유용주 ( Yong Zoo You ),김대일 ( Dae Il Kim ) 한국열처리공학회 2011 熱處理工學會誌 Vol.24 No.2

Single layer Sn doped In2O3(ITO) films and ITO 50 nm/Au 10 nm/ITO 40 nm (IAI) multilayer films were prepared with electron beam assisted magnetron sputtering on glass substrates. The effects of the Au interlayer, post-deposition atmosphere annealing and intense electron irradiation on the methanol gas sensitivity were investigated at room temperature. As deposited ITO films did not show any diffraction peaks in the XRD pattern, while the IAI films showed the diffraction peak for In2O3 (400). In this study, the gas sensitivity of ITO and IAI films increased proportionally with the methanol vapor concentration and an intense electron beam irradiated IAI film shows the higher sensitivity than the others film. From the XRD pattern, it is supposed that increased crystallization promotes the gas sensitivity. This approach is promising in gaining improvement in the performance of IAI gas sensors used for the detection of methanol vapor at room temperature.

The Effects of Negative Carbon Ion Beam Energy on the Properties of DLC Film

Choi Bi Kong,Choi Dae Han,Kim Yu Sung,Jang Ho Sung,Lee Jin Hee,Yoon Ki Sung,Chun Hui Gon,You Young Zoo,Kim Dae Il 한국표면공학회 2006 한국표면공학회지 Vol.39 No.3

The effects of negative carbon ion beam energy on the bonding configuration, hardness and surface roughness of DLC film prepared by a direct metal ion beam deposition system were investigated. As the negative carbon ion beam energy increased from 25 to 150 eV, the sp³ fraction of DLC films was increased from 32 to 67%, while the surface roughness was decreased. The films prepared at 150 eV showed the more flat surface morphology of the film than that of the film prepared under another ion beam energy conditions. Surface roughness of DLC film varied from 0.62 to 0.22 ㎚ with depositing carbon ion beam energy. Surface nanohardness increased from 12 to 57 Gpa when increasing the negative carbon ion beam energy from 25 to 150 eV, and then decreased when increasing the ion beam energy from 150 to 200 eV.