• 한국주조공학회지
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• 제17권5호
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• pp.443-449
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• 1997

The purpose of this study is to investigate the effect of P addition and homogenizing heat treatment on the mechanical properties of Cu-Sn-Ni alloy. The addition of P was 0.025wt.%P to 0.085wt.%P and homogenizing heat-treated at 400, 500, $600^{\circ}C$ under $N_2$ gas atmosphere. Mechanical properties was investigated in this study were Rockwell hardness, tensile strength, and elongation. Tensile strength and elongation increased with P and homogenizing time. Temperature was significantly influence on mechanical properties. Hardness decreased with increasing homogenizing time and temperature, but 0.085wt.%P specimen was showed higher hardness and lower tensile strength and elongation than 0.073wt.%P specimen due to the presence of more $Cu_3P$ in matrix.

• 한국주조공학회지
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• 제17권5호
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• pp.450-457
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• 1997

Effects of Ti addition and homogenizing heat treatment on the mechanical properties in Cu-Zn-Al alloy (high strength yellow brass) were investigated. Grain refinement was successfully achieved by Ti addition. The microstructure, which was composed of island or fine feather-like branched Ti compounds was changed to feather-like eutectic microstructure as the content of Ti increased. The highest hardness value was obtained for 0.5 wt.% Ti specimen and the second was Ti non-added specimen in as-cast condition. The highest tensile strength was obtained for 0.5 wt.% Ti specimen. Because of the presence of cast defects and worse castability, tensile strength decreased as the content of Ti increased. Elongation increased with increasing homogenizing time and temperature; remarkable increase was obtained for $400^{\circ}C$ homogenizing temperature in the 0.5 wt.% Ti specimen. For $500^{\circ}C$ and $600^{\circ}C$ homhgenizing, temperature, high elongation was obtained in 2 and 4 wt.% Ti specimen.

• 대한금속재료학회지
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• 제47권4호
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• pp.242-247
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• 2009

On the Transient Liquid Phase Bonding (TLPB) phenomenon with the MBF-50 insert metal at narrow gap (under 100), it takes long time for the bonding and the homogenizing. Typically, isothermal solidification is controlled by the diffusion of depressed element of B and Si. However, the amount of B and Si in the MBF-50 filler metal is large. This is reason of the long bonding time. Also, the MBF-50 filler metal did not contained Al and Ti which are ${\gamma}^{\prime}$ phases former. This is reason of the long homogenizing time. From the bonding phenomenon with the MBF-50 insert metal, we search main factors on the bonding mechanism and select several insert-metals for using the wide-gap TLPB. New insert-metals contained Al and Ti which are ${\gamma}^{\prime}$ phases former and decrease the B then the MBF-50. When the new insert-metal was used on the TLPB, the bonding time was decreased about 1/10 times and homogenizing heat treatment was no needed. In spite of the without homogenizing, the volume fraction of ${\gamma}^{\prime}$ phases in the boned interlayer was equal to homogenizing heat treated specimen which was TLPB with the MBF-50. Finally, the new insert metal named WG1 for the wide-gap TLPB is more efficient then the MBF-50 filler metal without decreasing the bonding characteristic.

• 한국재료학회지
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• 제5권1호
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• pp.132-139
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• 1995

Al-Mg-Cu-Mn계 합금을 가공열처리하고 초소성 특성을 조사한 후 광학 및 전자 현미경을 이용하여 초소성에 영향을 미치는 주요한 인자들을 조사하였다. 균질화 과정에서 제거되지 않은 조대한 2차상들은 그 후의 가공열처리 과정에서도 계속 잔류하여 초소성 변형 중 기공을 유발함으로써ㅓ 초소성 신율을 저하시켰다. 반면에 가공열처리 과정에서 생성된 미세한 석출물은 결정립 성장을 억제하여 조직을 안정화함으로써 초소성 특성을 향상시켰다. 균질화처리 조건은 2차상의 크기과 분포에 큰 영향을 주어 2단계 균질화-공냉처리는 1단계 균질화-노냉처리보다 조대한 2차상의 제거와 미세석출물의 생성에 효과적이었다.

• 한국식품영양과학회지
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• 제35권10호
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• pp.1434-1438
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• 2006

본 실험은 식품첨가물을 사용하지 않고 두유를 제조하는데 목적이 있다. 이를 위해 일반적으로 두유제조시 사용되는 유화제인 monoglyceride를 사용하지 않고 균질기 압력만을 변화시켜 제조할 경우 유화안정성에 미치는 영향을 알아보고자 하였다. 두유는 콩과 물의 비율을 1:8로 하여 제조하였으며 두유의 수율은 콩의 5.87배로 측정되었다. 균질기의 압력을 $50kg/cm^2,\;100kg/cm^2,\;150kg/cm^2,\;200kg/cm^2$로 달리하여 두유를 제조한 후 중심부의 일반성분을 분석한 결과 유화압력이 높을수록 지질의 함량이 높게 나타났다. 또한 시간의 경과에 따른 고형분의 침전정도를 측정한 현탁안정성과 열처리에 따른 분리정도를 측정한 유화안정성 그리고 점도측정결과 역시 유화압력이 높을수록 우수한 결과를 보여주었다. 실험결과 유화제를 첨가하지 않고 균질기 압력을 $150kg/cm^2$ 이상으로 유지하는 것만으로도 두유제조가 가능할 것으로 생각되었다.

• Transactions on Electrical and Electronic Materials
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• 제9권5호
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• pp.209-212
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• 2008

We developed a simple and effective purification method to obtain high-purity single-walled carbon nanotubes (SWCNTs) with low surface damage. The purification process consists of oxidization at $430^{\circ}C$ for 1 h in a furnace system of air atmosphere and homogenization in dilute hydrochloric acid solution for extremely short time. The role of homogenizer was examined during purification process in terms of purity and quality of purified SWCNTs. High-purity and low surface damage of SWCNT products was obtained using homogenizer which was operated at 8500 rpm for 10 min in the environment of 7 % HCI solution. From XRD spectra, we observed that metal catalysts were thoroughly removed. Raman spectra showed that the intensity values of crystallization ($I_{G}/I_{D}$) of purified SWCNTs were very similar with that of pristine SWCNTs. Moreover, the structure damage of purified SWCNTs was hard to find from electron microscopy. Consequently, homogenizing, which is a quick and simple manner, can be promising method for obtaining final SWCNTs with clearly high purity and crystallinity.

• Tribology and Lubricants
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• 제19권5호
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• pp.285-291
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• 2003

Ultrasonic vibrator is an equipment which atomizes and homogenization the oils by breaking the oil particles with ultrasonic cavitation, and would improve the properties. The present study deal with the ultrasonic breaking systems which recycle the shipborne waste oil into usable oil to be burnt. The first place, experimental studies were carried out to investigate the homogenizing effect of the waste oils by ultrasonic cavitation. Variation of the properties(viscosity, specific gravity and pH) and the matrix structures for the various shipborne waste oils were interpreted to analyse the breaking, dispersion effects by ultrasonic cavitation. The experimental results can be useful to the development of waste oil disposing systems.

• Journal of Pharmaceutical Investigation
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• 제17권1호
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• pp.41-46
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• 1987

Oil in water microemulsion containing soybean oil and egg phosphatide was prepared by vacuum high shear mixing and high pressure homogenizing. The laser particle sizer, Coulter counter and photomicroscope were used to determine the particle size distribution at each cycle of homogenizing. Particularly, the laser particle sizer(dynamic light scattering method) was applied to the study of particle size distribution behavior below $1\;{\mu}m$. It was found that the particle size distribution below $1\;{\mu}m$ was shifted to lower size range as the number of passing cycle was increased. Beyond the 7th cycle, however, the particle size distribution was not varied.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2001년도 추계학술발표회
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• pp.17-24
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• 2001

The sludge oils were produced necessarily in the ships operation, so that it will be the best way to manage the sludge oils inside ship itself from a viewpoint of the prevention of marine oil pollution from ship. The present study deal with the ultrasonic breaking systems which recycle the sludge oil from ships into usable oil to be burnt. The first place, experimental studies were carried out to investigate the homogenizing effect of the marine oils by repeated vibration of ultrasonic transducer. Variation of the properties(viscosity, specific gravity and pH) and the matrix structures for the environment of various marine oils were interpreted to analyze the breaking, dispersion effects by cavity. The experimental results can be useful to the development of sludge oil disposing systems.

• Journal of Welding and Joining
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• 제21권3호
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• pp.78-84
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• 2003

The changes of microstructure and hardness of TLP bonds of directionally solidified Ni base superalloy, GTD-111, with variation of homogenizing and aging treatment were investigated. The specimens were bonded at 1403K for 7.2ks using different insert metals such as MBF-50, MBF-80 and MBF-90 and they were homogenized at 1393K with various holding time. At center of bonded interlayer homogenized for hold time 30h, the contents of aluminum and titanium were approximately 90% and 95% of base metal, respectively. In this study, aging was performed at three different kinds : one step aging ; 1113K $\times$ 16h, two step aging ; 1113K $\times$ 10h ⇒ 1103K $\times$ 10h, three step aging ; 1113K $\times$ 10h ⇒ 1103K $\times$ 8h ⇒ 922K $\times$ 24h. ${\gamma}$' volume fraction and hardness of joints were high in the sequence of one step, two step and three step aging, whereas ${\gamma}$' volume fraction and hardness of joints obtained by three step aging treatment were higher than those of raw material. Tensile properties of joints bonded with MBF-80 and MBF-90, homogenized at 1393K for 30h and then three step aged became excellent than those of raw material, however, joint bonded with MBF-50 was poor.