A1-Cu 合金粉末의 燒結品에 關한 時效硬化

南勝義,尹太鴻,趙誠秀 弘益大學校 1985 弘大論叢 Vol.17 No.2

During compaction and sintering premixed Al-Cu powders, the effects of green density, sintering temperature and sintering time on dimensional change and hardness in sintered specimens were discussed and the phenomena of all conditions during age hardening were examined. The specimens were sintered in nitrogen atmosphere at temperatures ranging from 560℃ to 620℃ for 10, 20, 30 and 60 minutes. The dimensional changes of specimens during sintering are occurred in no time as the sintering temperature increased, and the expansion is occurred largely as the green density increased. The magnitude of peak hardness to age hardening is similar to wrought parts.

Meehanite 鑄鐵에서의 接種效果에 關한 硏究

南勝義,李龍鎬 弘益大學校 1981 弘大論叢 Vol.13 No.-

The main preperties of Meehanite are its pearlitic matrix with fine flake graphite, excellent uniformity, machinability, dimension stability and wear resistance. The effects of Carbon Equivalent and Inoculants on Ca-Si is mechanical property and uniformity were studied in relation to cast iron melted in a low friquency induction Furance and the Cupola. The possibility for the production of Meehanite in the Cupola was also studied. The results are as follows: (1) The mechanical properties are proportional to he amount of Inoculants and inversely proportional to the Carbon Equivalent. (2) The Uniformity is proportional to the amount and inversely proportional to the Carbon Equivalent. (3) Meehanite can be produced in Cupola by the inoculation of Ca-Si more than 0.3% above 1,450℃ into the molten metal which is white Cast Iron as cast state. 1. 서 론 2. 실험방법 2.1 실험시설 2.2 사용원료 2.3 용해작업 2.3.1 접종제 Ca-Si의 접종효과 2.4 접종방법 2.5 주 조 2.6 경화능 2.7 조직검사 3. 실험결과 3.1 탄소당량의 영향 3.2 접종제 Ca-Si의 영향 3.3 균질성 3.4 경화능 3.5 현미경조직 4. 고 찰 5. 결 론 The main preperties of Meehanite are its pearlitic matrix with fine flake graphite, excellent uniformity, machinability, dimension stability and wear resistance. The effects of Carbon Equivalent and Inoculants on Ca-Si is mechanical property and uniformity were studied in relation to cast iron melted in a low friquency induction Furance and the Cupola. The possibility for the production of Meehanite in the Cupola was also studied. The results are as follows: (1) The mechanical properties are proportional to he amount of Inoculants and inversely proportional to the Carbon Equivalent. (2) The Uniformity is proportional to the amount and inversely proportional to the Carbon Equivalent. (3) Meehanite can be produced in Cupola by the inoculation of Ca-Si more than 0.3% above 1,450℃ into the molten metal which is white Cast Iron as cast state.

機械的合金化法에 依한 V-A1合金의 非晶質化에 關한 硏究

南勝義,金夏榮 弘益大學校 科學技術硏究所 1991 科學技術硏究論文集 Vol.1 No.-

The formation of brittle intermetallic compound such as VAl₃tends to lower the toughness of VAl alloys. Also, due to the high melting point of vanadium, it is difficult to make that alloy by previous ingot metallurgy method. To depress the formation o intermetallic compound by making amorphous phase, mechanical alloying technique has been adopted. The effect of particle size and milling time on the phase has been thoroughly studied. For mechanical alloying, SPEX mixed/ mill has been used. The milling time and the composition of V and Al are varied to find the optimum condition of forming amorphous phase. The X-Ray Diffrection pattern, microstructure detection, microhadness test, experiments are carried out to analyze the MA product. The procedure of mechanical alloying is as follows; welding-equiaxed particle formation-random welding orientation-steady state. When the final step is reached, no lamellar-structure is detected. The steady state condition is observed after 8 hours and 10 hours milling for 15wt.% Al and 30wt.%Al alloy, respectively. The microhardness continuously increases up to 10 hours after then it remains constant.

흡연력을 고려한 궤양성 대장염 발생과 충수 절제술 사이의 상관 관계

남승우,양석균,정훈용,심기남,조병동,김승용,박의련,홍원선,민영일 大韓消化器病學會 1998 大韓消化器病學會誌 Vol.32 No.1

國産高張力鋼의 熔接部의 機械的 性質에 關한 硏究

南勝義,金聖培,金錫胤 弘益大學校 1982 弘大論叢 Vol.14 No.2

A study has been performed on the mechanical properties and the micro-structure of the welded zone in the high tensile steel produced in Korea. The experimental results indicated that the tensile strength and the hardness were increased in welded zone. The micro-structure of the welded zone was finer than that of the base metal. It may be considered that the increase of the mechanical properties is due to the chemical composition of electrode being different from the base metal and to the structure getting finer through the course of solidification.

전산화단층촬영술을 이용한 만성중이염 환자 측두골에 대한 고찰

남승일,고의경,이창헌,김유찬,구수권,이상화,전경명 대한이비인후과학회 1999 대한이비인후과학회지 두경부외과학 Vol.42 No.7

Pearlite성장속도에 미치는 합금원소 첨가효과의 속도론적 고찰

南勝義,安東勳 弘益大學校 1982 弘大論叢 Vol.14 No.2

The addition of an alloying element results in remarkable reduction of the rate of pearlite growth. In this paper, the effects of alloying elements on the kinetics of pearlite growth are investigated for Ni, Mn, Si, Cr, Mo. The mechanism for the effect of alloying elements is studied with a data or growth velocity and interlamellar spacing. The most important results in this paper are as follows. Strong carbide forming elements change the boundary (interfacial) diffusion for volume diffusion of carbon in the range of low temperature(below the Tp temperature) because the carbides prevent a cargbon from diffusing by interfacial route. In the systems that involve the elements which are not strong carbide formers, it is thought that the reactions are proceeded by a interfacial diffusion model with an activation energy of about 24,000 cal/mol.

만성 화농성 중이염의 세균학적 고찰

윤신의,문문만,김승찬,박희완,나한조,최봉남 朝鮮大學校 附設 醫學硏究所 1991 The Medical Journal of Chosun University Vol.16 No.1

The chronic suppurative otitis media is one of the most common disease in the otologic field. And the works on bacterial distribution of chronic suppurative otitis media were studied by many otologist, but there is some difference. The bacteriologic study was done on 126 cases of chronic suppurative otitis media who visited the Department of Otolaryngology, Chosun University Hospital between January 1989 and December 1989 and the following conclusions were obtained. 1) In sex distribution, the male had higher incidence rate than female (M: 56.3%, F:43.7%). 2) In age distribution, 3rd decade (34.1%), 2nd decade (34.1%), were most prevalent. 3) In duration of the disease, the hightest frequence was below 5 years duration 4) Among 126 cases, 98 cases(77.8%) were unilateral (right ear was 47 cases(37.3%) and left ear was 51 cases(40.5%))and 28 cases(22.2%) were bilateral. 5) The 136 cases(88.3%) showed the positive results under culture, but 18 cases(11.7%) didn't growthed. Among 136 cases 95 cases(61.7%) had single infection and the 41 cases(26.6%) had mixed infection. 6) The most frequently isolated bacteria was staphylococcus(38 strains, 27.9%) and next were proteus(27 strains, 19.9%) and pseudomonas (22 strains, 16.2%). 7) The Staphylococcus was sensitive to cephalothin(94.7%), amikacin(78.9%) and resistant to penicaIin(63.2%). 8) The Proteus was sensitive to amikacin(92.6%), cephalothin(88.9%) and resistant to minocycline(81.5%) and gentamicin(70.4%). 9) The Pseudomonas was sensitive to amikadn(86.4%), gemtamicin(59.1%) and resistant to minocycline(90.9%), ampicillin(86.4%) and cephalothin(86.4%).

하지층 종류에 따른 DLC 막의 접착력 및 잔류응력 변화

崔雲,南勝義 弘益大學校 科學技術硏究所 1996 科學技術硏究論文集 Vol.7 No.1

In this study, hydrogenated diamond-like-carbon (DLC) films were synthesized by rf plasma deposition system, and their residual stresses, and adhesions were extensively investigated. The best adhesion with substrates was observed in the Si substrates. The adhesion strength was generally decreased with an order of Si>metal>ceramics. The adhesion is strongly enhanced by the formation of carbides at the interfaces, while deteriorated by the formation of interface oxides occurring during plasma processes. When the polycrystalline Si substrates in stead of single crystal Si are used, the peak stresses are reduced to be 1∼3 GPa indicating the dependency of generated stresses on the microstructures and density of Si substrates.

FeTaN 연자성 박막을 이용한 자기 평면 인덕터 소자의 고주파 특성에 관한 연구

金充植,南勝義,韓相龍 弘益大學校 科學基術硏究所 1999 科學技術硏究論文集 Vol.10 No.2

In accordance with tendency to miniaturization and high frequency operation of electronic products, extensive efforts of miniaturizing magnetic devices such as inductors, transformers which can be applicable to the small scale power supply (DC-DC converter). To fabricate high performance inductors in small area, several important factors should be considered, such as magnetic films with good soft magnetism, induction coil with low resistance, and well-designed geometrical inductor structures. Usually, permalloy or Co-based amorphous films have been used for the soft magnetic films. However, in order to improve the inductor performance, especially for the high current applications such as DC-DC converters, a soft magnetic material with a higher saturation magnetization (4πMs) and extrinsic anisotropy field is needed. Inductor performance without any planarization process for the upper magnetic layers was far less than that expected from the theoretical calculation. Nevertheless, uniaxial magnetic anisotropy was induced to the magnetic flux direction, the soft magnetic properties and the inductor performance were degraded due to the grating topology of upper magnetic films. Glass bonding is a useful method for achieving a completely planar inductor structure. The planar inductor with glass bonding shows excellent performance: inductance(L)of 1.2 μH, figure of merit(Q) 7.5 (at 5 MHz), and the dc current capability up to 100 mA. In order to reveal the effect of anisotropy field on inductor performance, hard axis of magnetic layer was controlled as 0, 45 and 90 degree from magnetic field generated at rectangular spiral coil. Inductance is drastically decreased with increasing DC current over saturation current, and as increasing the angle miss match, the saturation current is appeared at low current.