The overall process, from the pre-treatment of aluminum substrates to the eco-friendly neutral electroless Ni-P plating process, was observed, compared, and analysed. To remove the surface oxide layer on the aluminum substrate and aid Ni-P plating, a zincation process was carried out. After the second zincation treatment, it was confirmed that a mostly uniform Zn layer was formed and the surface oxide of aluminum was also removed. The Ni-P electroless plating films were formed on the secondary zincated aluminum substrate using electroless plating solutions of pH 4.5 and neutral pH 7.0, respectively, while changing the plating bath temperature. When a neutral pH7.0 electroless solution was used, the Ni-P plating layer was uniformly formed even at the plating bath temperature of 50 oC, and the plating speed was remarkably increased as the bath temperature was increased. On the other hand, when a pH 4.5 Ni-P electroless solution was used, a Ni-P plating film was not formed at a plating bath temperature of 50 oC, and the plating speed was very slow compared to pH 7.0, although plating speed increased with increasing bath temperature. In the P contents, the P concentration of the neutral pH 7.0 Ni-P electroless plating layer was reduced by ~ 42.3 % compared to pH 4.5. Structurally, all of the Ni-P electroless plating layers formed in the pH 4.5 solution and the neutral (pH 7.0) solution had an amorphous crystal structure, as a Ni-P compound, regardless of the plating bath temperature.

The formation behavior of a passive state film on the surface of STS304 in electrolytic solution was analyzed to determine its metallic ion composition. The properties of passive state films vary depending on the Fe and Cr ions in the electrolytic solution. It was observed that the passive state film surface became flat and glossy as the concentration of Fe and Cr ions in the electrolytic solution increased. The corrosion resistance property of the passive state film was proportional to the amount of Fe and Cr in the electrolytic solution. An initial passive state film with high Fe concentration was formed on the surface of STS304 during early electrolytic polishing. Osmotic pressure of Fe ions occurs between the passive state film and electrolytic solution due to the Fe ion concentration gradient. The Fe in the passive state film is dissolved into the electrolyte, and Cr fills up the Fe ion vacancies. As a result, a good corrosion-resistant floating film was formed. The more Fe ions in the electrolytic solution, the faster the film is formed, and as a result, a flat passive state film containing a large amount of Cr can be formed.

In this study, a new, relatively simple fabrication method for forming a mesoporous Al(OH)3 film onAl substrates was demonstrated. This method, i.e., alkali surface modification, was simply comprised of dippingthe substrate in a 5×10-3M NaOH solution at 80oC for one minute and then immersing it in boiling waterfor 30 minutes. After alkali surface modification, a mesoporous Al(OH)3 film was formed on the Al substrate,and its chemical state and crystal structure were confirmed by XPS and TEM. According to the results of theXPS analysis, the flake-like morphology after the alkali surface modification was mainly composed of Al(OH)3,with a small amount of Al2O3. The mesoporous Al(OH)3 layer was composed of three regions: an amorphous-rich region, a region of mixed amorphous and crystal domains, and a crystalline-rich region near the Al(OH)3layer surface. It was confirmed that the stabilization process in the alkali surface modification stronglyinfluenced the crystallization of the mesoporous Al(OH)3 layer.

The 21st Century Frontier Program, which is one of the R&D programs funded by Korean government, was launched in 1999 to elevate the status of Korean science and engineering capabilities to the advanced nation in the strategic fields. Currently, 23 different fields of science and engineering programs are carried out by researchers in institutes, universities and industries. Center for Advanced Materials Processing (CAMP) was formulated in 2001 to develop the advanced materials as well as to improve the parts manufacturing process. The main role of CAMP is proposing and forecasting the long term vision in Materials Processing Technology and also supporting the project teams for their best performance in R&D. The CAMP program consists of 5 research areas such as, Multi-layer Ceramic Electronic Parts, Powder Formed Precision Parts, 3 Dimensional Polymer Based Composites, Functional Metal Sheets, Parts Integration Technology. An introduction of R & D activities at CAMP, specially focusing on powder metallurgy, wil be presented.

Taguchi methodology has been applied to get an idea about the parameters related to the chemical vapour deposition technique, which influences the formation of semiconducting carbon thin film of a desired band gap. L9 orthogonal array was used for this purpose. The analysis based on Taguchi methodology suggests that amongst the parameters selected, the temperature of pyrolysis significantly controls the magnitude of band gap (46%). Sintering time has a small influence (30%) on the band gap formation and other factors have almost no influence on the band gap formation. Moreover this analysis suggests that lower temperature of pyrolysis (≤ 750℃) and lower time of sintering (≤ 1 h) should be preferred to get carbon thin film with the desired band gap of 1.2eV.

Film properties of monodispersed model composite latexes with particle size of 190 nm, which consist of n-butyl acrylate as a soft phase monomer and methyl methacrylate as a hard phase monomer with different morphology was examined. Five different types of model latexes were used in this study such as random copolymer particle, soft-core/hard-shell particle, hard-core/soft-shell particle, gradient type particle, and mixed type particle. Tensile strength and tensile elongation at break of final films were evaluated. Those properties can be interpreted in terms of PBA/PMMA phase ratio and their morphology. The interfacial adhesion strength was also evaluated using 180˚ peel strength measurement and cross hatch cutting test.

In this study, various model composite latexes were synthesized using n-butyl acrylate and methyl methacrylate as comonomers by seeded multi-staged emulsion polymerization. Monodispersed model composite latex particles with size of 190 nm and polydispersity index of 1.05, which have various morphology including random copolymer particle, soft-core/hard-shell particle, hard-core/soft shell particle, and gradient-type copolymer particle, homopolymers particles were prepared. The designed morphology of model composite particles were confirmed.

발전소 복수기의 열전달 표면에 형성되는 불순물의 fouling factor와 튜브내면에 부착되는 피막의 두께변화를 측정하여 복수기 관리에 관한 지침을 제시하고자 모델복수기를 이용하여 60일간 현장실험을 실시하였다. 복수기의 fouling factor는 시험 후 약 40일 이후부터 큰 폭으로 증가하였다. 발전용 복수기의 관청결도가 85-90%로 설계되므로 설계치를 유지하기 위해서는 약 40일 마다 복수기튜브를 세정하여 관청결도를 향상시켜야 할 것으로 판단되었다. 또한 동합금 재질을 사용하는 복수기튜브는 설치 후 보호피막이 형성되는 초기 30일 동안의 방식운전이 복수기튜브 건전성 확보에 중요한 인자임을 유추할 수 있었다.

다이아몬드 증착시 기판의 표면처리를 변화시켰을 때 다이아몬드의 핵생성 밀도에 미치는 영향에 대하여 연구하였다. 실험장치는 열 필라멘트 CVD 장치를 사용하였고, 반응가스로 메탄과 수소가스를 사용하였다. 기판의 표면 처리는 탄소 상을 기판에 증착시키는 방법, Soot에 의한 기판 표면처리, 혹연에 의한 기판 표면처리로 크게 3가지로 행하였다. 모든 경우에 핵생성 밀도가 증가하였으나 탄소 상을 증착시킨 경우와 soot에 의한 사전처리의 경우의 핵생성 밀도의 증가가 혹연에 의한 처리보다 더 현저하였다. 또한 탄소강의 증착의 경우 표면에 굴곡이 없는 매우 평탄하고 균일한 다이아몬드 막을 얻을 수 있었다. 사전증착처리 한 기판에 탄소 층을 형성시켰을 때 탄소 층과 기판과의 접착력이 약한 것을 이용하여 다이아몬드 막을 쉽게 분리시켜 free standing 다이아몬드 박막을 얻을 수 있음을 알았다.

전자빔 증착법을 사용하여 Ti과 Co를 Si(100) 단결정, 다결정 Si 및 SiO2기판에 증착한 후 900˚C에서 20초 급속 열처리하여, Co/Ti 이중박막으로부터의 실리사이드화 반응을 조사하였다. 단결정 시편의 경우 Ti의 두께를 5~6mm로 최소화함으로서 두께가 균일하고 기판과의 계면이 평탄하며 비저항이 낮고 열적 안정성이 높은 CoSi2 에피박막을 형성할 수 있었다. 그러나 다결정 시편에는 두께와 계면이 불균일하고 열적으로도 불안정한 다결정의 CoSi2와 그 위에 두개의 Co-Ti-Si혼합층이 형성되었다. 한편 SiO2 우에 증착된 Co/Ti은 열처리를 하여도 확산하지 않고 그대로 남아 있어서, Co/Ti 이중박막의 SiO2와의 반응성이 미약함을 보여 주었다.

전자빔 증착법을 사용하여 10nm두께의 Ti과 18nm두께의 Co를 Si(100)기판에 증착한 후, N2분위기에서 900˚C, 20초 급속 열처리하여, Co/Ti 이중금속박막의 역전을 유도함으로서 CoSi2박막을 형성하였다. 4점 탐침기로 측정한 면저항은 3.9Ω/ㅁ 었으며, 열처리 시간을 증가해도 이값은 유지하여 열적 안정성을 나타내었다. XRD 결과는 형성된 실리사이드는 기판과 에피관계를 갖는 CoSi2상 임을 보였으며, SEM 사진은 평탄한 표면을 나타내었다. 단면 TEM 사진은 기판위에 형성된 박막층은 70nm 두께의 CoSi2 에피박막과 그위에 두개의 C0-Ri-Si합금층등 세개의 층으로 되어 있음을 보였다. AES 분석은, 기판상의 자연산화막을 형성할 수 있었음을 보여주었다. AES분석은, 기판상의 잔연산화막이 열처리초기, Ti에 의해 제거된후 Co가 원자적으로 깨끗한 Si기판에 확산하여 CoSi2에피박막을 형성할 수 있었음을 보여주었다. 700˚C, 20초 + 900˚C, 20초 이중 열처리를 한 경우, CoSi2결정성장으로 면저항값은 약간 낮아졌으나, 박막의 표면과 계면이 거칠었다. 이 CoSi2에피박막의 실제 소자에의 적용방안과 막의 역전을 통한 에피박막형성의 기제를 열역학 및 kinetics 관점에서 고찰하였다.

본 실험은 오리엔탈 나리 ‘Siberia’ 품종을 유공비닐 봉지에서 인편삽시 인편 착생부위와 삽목조건에 따른 소인경의 형성과 생장을 조사하여 효과적인 소인경 생산 방법을 알아보고자 실시하였다. 착생부위에 있어서 내부보다는 외부와 중부인편이 소인경의 형성 및 생육이 양호하였다. 삽상의 온도는 15℃나 30℃보다 20℃와 25℃ 조건에서 소인경의 무게, 둘레, 높이, 수가 증가하였다. 용토 1L당 수분 400mL 처리는 타처리에 비해 소인경의 무게와 직경이 16% 정도 증가한 것으로 나타났다. 피트모스 단용과 피트모스:펄라이트:버미큘라이트를 1:1:1 혼합한 용토에서 소인경 생육이 양호하였다. 인편과 용토의 비율을 1:2하여 혼합한 후 인편삽을 하더라도 소인경 무게와 직경에는 큰 차이가 없었다.