• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.175-176
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• 2006

The filling property of the binder treated iron based powder made of atomized iron powder was compared with that of the one made of reduced iron powder. The latter one showed a better filling property than the former one, although the original reduced powder showed a worse flow rate. Changing the particle size distribution of the original atomized powder from wide to narrow like the original reduced iron powder, improved the filling property of the binder treated powder. As a result, the particle size distribution of the original iron powder was found to strongly affect the filling property of the binder treated powder.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.706-707
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• 2006

Premixes treated with a binder, such as in the FLOMET process, exhibit better flow, reduced dusting and segregation and improved productivity and part consistency compared to conventional premixes. The binder treatment is highly suitable for high performance P/M applications which often require premixes containing very fine alloying additives and excellent die filling characteristics. With this process, various binders and lubricants can be utilized in order to make premixes with unique properties. In this paper, the characteristics and performances of bonded premixes are reported.

• 한국세라믹학회지
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• 제31권8호
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• pp.823-828
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• 1994

Dispersion condition of Si3N4 powder in molten wax was established by comparing relative viscosity of mixture with 20 vol% solids loading, while the evaluation of compression-molded sample was demonstrated as an effective method for developing a binder system for injection molding. The best dispersion of Si3N4 powder in molten wax was achieved when Si3N4 powder was treated with 5% stearic acid, and the critical powder volume fraction was determined to be about 0.51 from density measurement of compression-molded samples. Samples containing polar secondary binder showed markedly improved green strength, higher thermal expansion and increased wicking rate in the early stage.

• 한국세라믹학회지
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• 제30권2호
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• pp.131-138
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• 1993

The effects of silane coupling agents on the injection molding process were investigated using silicone nitride mixtrues with a binder system containing polypropylene as a major binder (55vol% solid loading). The formation of bonding between silicon nitride powder and coupling agents was confirmed through the analyses of powder surface. The use of coupling agents improved mixing characteristics judged by the torque change during mixing process. the coupling agents also reduced molten viscosity of the mixture considerably, which is a main factor to determine the flow of the mixture. However, the bonding between coupling agents and polymers had a negative effect on the debinding process by retarding the thermal decomposition.

• 대한화장품학회지
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• 제24권3호
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• pp.105-110
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• 1998

In the make-up product, Eye-shadow products have several purposes of enhancing product quality such as providing the beauty (variation of shape, clean appearance), feeling, continuity and adhesion. In this paper, newly developed wet type back injection press process is introduced so as to increase higher value products which providing various the beauty. The solvent takes an essential role to provide the fluidity of the powder bulk during the pressed-process of wet type pressed product. In this study, the effect of solvent in the oil binder was investigated, And the higher quality condition of the wet type pressed product was built to apply cosmetic preparation. Firstly, the system was designed powder phase as non treated pigment. The oil binder phase is categorized as hydrocarbons(Mineral oil, Squalane), Silicones(Methicone, Dimethicone ), esters (Octyldodecanol, Octyl Dodecyl Myristate). The solvent phase used was C 7-8 isoparaffin and Isopropyl Alcohol. The interaction of oil binder and solvent is investigated by measuring mass of final oil binder and the each solubility parameter. It was found that the higher the solubility the higher the degree of change in the final composition of the oil binder. In order to maintain the quality of the final product, the solvent used in pressed-process should be hydrophobic with oil binder.

• 한국분말재료학회지
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• 제21권3호
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• pp.185-190
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• 2014

$FeS_2$ has been widely used for cathode materials in thermal battery because of its high stability and current capability at high operation temperature. Salts such as a LiCl-KCl were added as a binder for improving electrical performance and formability of $FeS_2$ cathode powder. In this study, the effects of the addition of $Li_2O$ in LiCl-KCl binder on the formability of $FeS_2$ powder compact were investigated. With the increasing amount of $Li_2O$ addition to LiCl-KCl binder salts, the strength of the pressed compacts increased considerably when the powder mixture were pre-heat-treated above $350^{\circ}C$. The heat-treatment resulted in promoting the coating coverage of $FeS_2$ particles by the salts as $Li_2O$ was added. The observed coating as $Li_2O$ addition might be attributed to the enhanced wettability of the salt rather than its reduced melting temperature. The high strength of compacts by the $Li_2O$ addition and pre-heat-treatment could improve the formability of $FeS_2$ raw materials.

• 한국잠사곤충학회지
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• 제43권1호
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• pp.41-48
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• 2001

The purification, dissolution and powdering of stained waste silk obtained from weaving and dyeing process were studied for the surface modification of textile fabric and plastic materials. The whiteness of stained waste silk could be improved through degumming and bleaching with sodium hydrosulfite. The water-soluble fibroin solution can be obtained by dissoving the degummed waste silk in a boiling solution of 50% calcium chloride for 60 minutes. The salts and heavy metals contained in fibroin solution were removed by electric dialysis, wool fiber filtration and gel filtration chromatography. The fibroin powder was prepared by using a fine grinder after the alkali treatment for weakening the silk fiber. The fine fibroin powder of particle size around 30 ㎛ was obtained with a ultra fine-mill, while it was finer below 10 ㎛ with a ball-mill. The dissolved or powdered silk was applied to the surface of fabric with addition of the binder (a urethane resin). The moisture content of polyester and nylon fabrics treated with the silk solution was improved due to hygroscopic property of silk. The fine fibroin powder mixed with the binder ws coated on the surface of synthetic film by use of the air pressed sprayer. It was revealed that the hygroscopicity as well as the softness of fibroin powder coated film was much improved. Therefore, it is thought that the fine silk fibroin powder is applicable as an coating agent for the surface modification of plastic and synthetic leather.

• Carbon letters
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• 제14권2호
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• pp.110-116
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• 2013

This study investigated a developed process for producing a composite bipolar plate having excellent conductivity by using coal tar pitch and phenol resin as binders. We used a pressing method to prepare a compact of graphite powder mixed with binders. Resistivity of the impregnated compact was observed as heat treatment temperature was increased. It was observed that pore sizes of the GCTP samples increased as the heat treatment temperature increased. There was not a great difference between the flexural strengths of GCTP-IM and CPR-IM as the heat treatment temperature was increased. The resistivity of GPR700-IM, heat treated at $700^{\circ}C$ using phenolic resin as a binder, was $4829{\mu}{\Omega}{\cdot}cm$ which was best value in this study. In addition, it is expected that with the appropriate selection of carbon powder and further optimization of process we can produce a composite bipolar plate which has excellent properties.

• 대한화학회지
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• 제8권3호
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• pp.98-102
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• 1964

As a practical method to produce the carbonaceous binder, the destructive distillation of coal tar has been studied. The optimum condition on binder in various temp. and cutting time were examined and the compositions of pitch were also examined in connection with ${\alpha},\;{\beta}\;and\;{\gamma}$ by solvent extraction. Coke powder was mixed with binder as treated pitch in the proportions of 77% of coke to 23% of pitch, to give a plastic mix which could then be pressed into molding. The properties of baked body after molding was tested. It was found that cutting of the coal tar at 350${\circ}C$, for 30 min., at 300${\circ}C$. for 1 hr., and at 250${\circ}C$. for 8 hrs. were good condition. Particularly, we found that the cutting of the coal tar obtained by destructive distillation at high temp. and in minimum period of time had shown the best condition for utilization of carbonaceous pitch as binder. The above mentioned cutting condition results in good quality of pitch which is available to be used as binder in carbon industry.

• 한국분말재료학회지
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• 제23권6호
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• pp.437-441
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• 2016

Recently, the grain boundary diffusion process (GBDP), involving heavy rare-earth elements such as Dy and Tb, has been widely used to enhance the coercivity of Nd-Fe-B permanent magnets. For example, a Dy compound is coated onto the surface of Nd-Fe-B sintered magnets, and then the magnets are heat treated. Subsequently, Dy diffuses into the grain boundaries of Nd-Fe-B magnets, forming Dy-Fe-B or Nd-Dy-Fe-B. The dip-coating process is also used widely instead of the GBDP. However, it is quite hard to control the thickness uniformity using dip coating. In this study, first, a $DyF_3$ paste is fabricated using $DyF_3$ powder. Subsequently, the fabricated $DyF_3$ paste is homogeneously coated onto the surface of a Nd-Fe-B sintered magnet. The magnet is then subjected to GBDP to enhance its coercivity. The weight ratio of binder and $DyF_3$ powder is controlled, and we find that the coercivity enhances with decreasing binder content. In addition, the maximum coercivity is obtained with the paste containing 70 wt% of $DyF_3$ powder.