• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1023-1024
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• 2006

Al-8Fe-2Mo-2V-1Zr alloys were prepared by the gas atomization/hot extrusion and the melt spinning/hot extrusion. For the gas atomized and extruded alloy, equiaxed grains with the average size of 400 nm and finely distributed dispersoids with their particle sizes ranging from 50nm to 200nm were observed. For the melt spun and hot extrusion processed alloy, refined microstructural feature consisting of equiaxed grains with the average size of 200nm and fine dispersoids with their particle sizes under 50nm appeared to exhibit a difference in microstructure. Strength of the latter alloy was higher than that for the former alloy up to elevated temperatures.

• 한국염색가공학회지
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• 제11권4호
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• pp.8-15
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• 1999

Electroconductive fiber was obtained by acryl fiber treated with $CuSO_4$. The Properties and structure of fiber and fabric such as mechanical property, electrical conductivity, fine structure, electrification were investigated. The experimental results are as follows 1) The electrical conductivity of the conducting fiber was greatly increased but fine structure and physical properties were similar to acryl fiber 2) Fabric made by mix spinning with conducting fiber was shown great electrification effect. 3) In the mix spinning with conducting fiber, it was necessary to use different. finishing such as milled finish because stiffness of fabric made by mix spinning with conducting fiber was increased and elastic recovery was decreased. 4) The antimicrobial activity of electroconductive fiber blended wool was effective by Cu component for shake flask test.

• 한국분말재료학회지
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• 제5권1호
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• pp.50-56
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• 1998

A new process using rapid solidification (melt spinning method) followed by pressing and sintering was investigated to produce the n-type thermoelectric ribbons of 90% $Bi_2Te_3$+10% $Bi_2Se_3$ doped with $CdCl_2$. Quenched ribbons are very brittle and consisted of homogeneous $Bi_2Te_3-Bi_2Se_3$ pseudo-binary solid solutions. Property variations of the materials was investigated as a function of variables, such as dopant $CdCl_2$ quantity and sintering temperature. When the process parameters were optimized, the maximum figure of merit was $2.146{\times}10^{-3}K^{-1}$.

• Fibers and Polymers
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• 제6권2호
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• pp.95-102
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• 2005

Sodium cellulose carbonate (CC-Na) dissolved in $8.5\;wt\%$ NaOH/ZnO (100/2-3, w/w) aqueous solution was spun into some acidic coagulant systems. Diameter of regenerated cellulose fibers obtained was in the range of $15-50\;{\mu}m$. Serrated or circular cross sectional views were obtained by controlling salt concentration or acidity in the acid/salt/water coagulant systems. Velocity ratio of take-up to spinning was controlled up to 4/1 with increasing spinning velocity from 5 to 40 m/min. Skin structure of was developed at lower acidity or higher concentration of coagulants. Fineness, tenacity and elongation of the regenerated cellulose fibers were in the range of 1.5-27 denier, 1.2-2.2 g/d, and $8-11.3\;\%$, respectively. All of CC-Na and cellulose fibers spun from CC-Na exhibited cellulose II crystalline structure. Crystallinity index was increased with increasing take-up speed.

• 한국염색가공학회지
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• 제10권5호
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• pp.13-18
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• 1998

Polypropylene-ethylene/vinyl acetate copolymer (PP-EVA) blends were prepared by mechanical blending using relatively semi-crystaline ethylene-vinyl acetate copolymer and polypropylene. In order to obtain dyeable PP fiber, PP-EVA blends were prepared using below 10wt.％ of EVA and formed a filament by the melt spinning method. The resultant fibers had tensile strengh of 2∼3g/d, elongation of 330∼600%, initial modulus of 22∼46g/d, and exhibited markedly improved dyeing property.

• 한국의류산업학회지
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• 제15권4호
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• pp.606-612
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• 2013

This paper investigates the physical properties of organic cotton staple yarns manufactured by ring and siro spinning methods as well as analyzes the physical properties of fabric specimens knitted with staple yarns made by these two methods. The breaking stress and evenness of organic ring staple yarns showed the same level for the Japanese specimens as the control yarns; in addition, the same coefficient for the friction of the manufactured yarns and Japanese specimens was also shown. These results makes it possible to manufacture organic staple ring yarns from organic cotton fibers. The tenacity and breaking strain of siro staple yarns were higher than ring staple yarns. The evenness and friction coefficient of siro staple yarns were lower than the ring staple yarns; in addition, hairiness and the number of siro staple yarns was significantly lower than the ring staple yarns. The dimensional stabilities of knitted fabrics by 20 Ne and 30 Ne siro staple yarns were superior to ring staple yarns. The color fastnesses of washing, perspiration and abrasion of knitted fabrics by two spinning methods showed the same level as the 4.5 grade; however, the light fastness of knitted fabric by siro staple yarns was superior to ring staple yarns. It was shown that the siro spinning method (using eco-friendly organic cotton fibers) was applicable to a high sensible knitted garment that overcame drawbacks of organic fibers related to shrinkable properties after washing and low color fastness to light.

• 한국의류학회지
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• 제39권6호
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• pp.877-884
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• 2015

Polytrimethylene Terephthalate (PTT) is an eco-fiber with good elastic properties; however, it requires more detailed studies related to spinnability according to blending of various kinds of fibers. The evolution of spinning technology was focused on improved productivity with good quality; in addition, air vortex spinning was recently invented and applied on the spinning factory as the facility with good productivity and quality. More detail spinning technology according to the blending of various kinds of fibers on the air vortex spinning system is required to obtain good quality yarns for high emotional fabrics. In this paper, the physical properties of air vortex, compact and ring staple yarns using PTT/wool/modal blend fibers were investigated with yarn structure to promote high functional PTT that includes fabrics for high emotional garments. Unevenness of air vortex yarns was higher than those of compact and ring yarns; in addition, imperfections were greater than those of compact and ring yarns, which was attributed to a fascinated vortex yarn structure. Tenacity and breaking strain of air vortex yarns were lower than those of compact and ring yarns, caused by higher unevenness and more imperfections of air vortex yarns compared to compact and ring yarns. Vortex yarns showed the highest initial modulus and ring yarns showed the lowest ones which results in a stiff tactile feeling of air vortex yarns in regards to the initial modulus of yarns. Dry and wet thermal shrinkages of air vortex yarns were lower than ring yarns. Good shape retention of vortex yarns was estimated due to low thermal shrinkage.

• Composites Research
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• 제32권5호
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• pp.265-269
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• 2019

직접적으로 탄소 나노 튜브(CNT) 섬유를 방사하는 기술은 향후 고성능 소재분야에서 유망한 방법이다. 수직으로 정렬된 CNT 어레이에서 직접 방사하는 연구는 보고된 이래 연구가 활발히 진행되고 있다. 그러나, 보고된 CNT 어레이의 대부분은 방사성을 갖고 있지 않다. 이 연구에서는, 방사특성을 향상시기키 위해 촉매, 탄소원등의 조건을 제어함으로써, CNT의 방사성 정도가 CNT 어레이의 형태와 밀접하게 관련되어 있음을 증명하였다. 탄소원인 아세틸렌에 추가 탄소원으로 에틸렌을 첨가함으로서 CNT 어레이의 waviness를 감소시킬 수 있었으며, 이는 촉매의 활성화를 유도하여 CNT축 방향으로의 선형화를 증가시켰다. 또한 이러한 탄소원 조성의 변화는 촉매 입자의 유착(coalescence)을 제어함으로써, 어레이의 밀도 및 합성된 CNT의 직경 과 길이등 물성을 동시에 제어할 수 있었다. 합성된 CNT 어레이는 잘 정렬되어 있으며, 방사 가능한 어레이의 합성조건을 도출할 수 있었다.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2009년도 학술발표대회
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• pp.106-107
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• 2009

• 한국염색가공학회지
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• 제16권4호
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• pp.1-9
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• 2004

In recent, development of nano fiber has been one of the most active subjects in the world. Nano fiber is defined as a ultra fine yarn with a diameter unit of $10-100\times10^{-9}meter$, which is possible to be produced by an electro-spinning technology. In this study, physical characteristics and dyeing properties of nylon 66 nano fiber were investigated. Nylon 66 nano fiber was dyed with levelling type acid dyes. X-ray diffraction method and DSC analysis were used for the measurement of the degree of crystallization. Analysis of amino end groups was also performed in order to examine a relationship between number of amino groups and its dyeing property as well as water absorption behavior. The maximum exhaustion % of dyes and dyeing rate under various dyeing conditions, such as dyeing temperature and pH in dye bath, along with build-up properties for 2 acid dyes were evaluated. It was found that the degree of crystallization of nano fiber was smaller than that of regular fiber, and amino end groups of nano fiber were less than regular fiber. Half dyeing time of nano fiber was shorter than regular fiber because of the bigger specific surface area. Effect of pH on exhaustion % was small in case of nano fiber. Exhaustion of nano fiber increased with higher concentration of dye.