• Steel and Composite Structures
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• 제15권3호
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• pp.267-279
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• 2013

This article describes a simple and cost effective fabrication procedure by using hand lay-up technique that is employed for the manufacturing of thin-walled axi-symmetric composite shell structures with carbon, glass and hybrid woven fabric composite materials. The hand lay-up technique is very commonly used in aerospace and marine industries for making the complicated shell structures. A generic fabrication procedure is presented in this paper aimed at manufacture of plain Carbon Fabric Reinforced Plastic (CFRP) and Glass Fabric Reinforced Plastic (GFRP) shells using hand lay-up process. This paper delivers a technical breakthrough in fabrication of composite shell structures without any joints and wrinkling. The manufacture of stiffened CFRP shells, laminated CFRP shells and hybrid (carbon/glass/epoxy) composite shells which are valued by the aerospace industry for their high strength-to-weight ratio under axial loading have also been addressed in this paper. A fabrication process document which describes the major processing steps of the composite shell manufacturing process has been presented in this paper. A study of microstructure of the glass fabric/epoxy composite, carbon fabric/epoxy composite and hybrid carbon/glass/fabric epoxy composites using Scanning Electron Microscope (SEM) has been also carried out in this paper.

• 한국의류산업학회지
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• 제3권1호
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• pp.35-41
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• 2001

Dyeing properties of silk fabric with onion shell were studied by investigating the effect of dyeing conditions, such as concentration of onion shell, dyeing temperature, dyeing time and pH, on dye uptakes. And also the effects of mordants and mordanting methods or color change and dye uptakes were investigated. For the practical use, the various color fastness of dyed and mordanted fabric were evaluated. The color fastness was improved when Fe mordant was added.

• 폴리머
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• 제34권2호
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• pp.89-96
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• 2010

Methyl methacrylate(MMA), ethyl acrylate(EA), n-butyl acrylate(BA), styrene(St) 단량체를 수용성 개시제인 ammonium persulfate(APS)와 음이온 유화제인 sodium dodecyl benzene sulfonate(SDBS)를 사용하여 organic/organic core-shell 구조의 접착바인더를 중합 후 부직포와 피혁에 함침시키고 플라즈마 표면 처리 후 속도론적인 해석과 기계적인 물성을 평가하였다. Core-shell 바인더 중합시 전환율은 단량체의 조성이 등몰에서 MMA/EA, MMA/BA core-shell 복합입자 모두 90% 이상이 되었다. 등몰에서 부직포/부직포에 core-shell 복합입자를 함침시키고 플라즈마 처리 후의 상태접착 박리강도는 MMA/St, EA/BA, BA/MMA, EA/St, EA/MMA의 순으로 되었고, 또한 부직포/피혁에 core-shell 복합입자를 함침시키고 플라즈마 처리 후의 상태접착 박리강도는 MMA/BA, BA/EA, MMA/EA, St/MMA, EA/St의 순으로 되었다.

• 한국의류산업학회지
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• 제9권4호
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• pp.441-444
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• 2007

For the purpose of application to new natural dyestuff, the dyeability of Purple onion shell extract was analyzed. It was dyed in cotton fabric according to various dye weight, dyeing temperature, dyeing time. And the effects of mordanting conditions were examined as color differences and color fastnesses. The dyeaffinities were increased as were increased dye weight, especially 100% owf. The optimum dyeing condition of Purple onion shell extract was 40minutes at $60^{\circ}C$. The dyeaffinity was increased at pre-mordanted condition, and color difference was increased distinctly at post mordanted condition. The hue of all mordanted cotton fabrics changed into Yellow where as non mordanted cotton fabric was Red. The color fastnesses of mordanted cotton fabrics were generally not so god, but light fastness was improved in post-Cu mordanted fabric.

• The International Journal of Costume Culture
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• 제4권3호
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• pp.241-248
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• 2001

Re water resistance of shell fabrics intended for we in outdoor apparel was measured using three different standard test methods, ASTM D 751, hydrostatic resistance, procedure A(Mullen test -- with and without a fabric support) and Procedure B (Hydrostatic head test). A database of information on their water resistance performance was created. The data collected with different methods were correlated and the advantages and disadvantages of each method were compared. The Mullen test with a support appears to give higher and more favorable water resistance values on shell fabrics preventing fabric rupture during the test. The hydrostatic head test gave lower hydrostatic pressure values than those measured on the two Mullen tests. The Mullen test is recommended for testing the water resistance of fabrics that high a relatively high water resistance because the Mullen tester applies a wide range of pressure. The hydrostatic head test is recommended for testing the fabrics that have relatively low water resistance. The area of the fabric sample that is in contact with the water is smaller in the Mullen test, so higher pressure levels can be reached and more samples should probably be tested to get a representative value for each fabric types. Furthermore, the hydrostatic head test was deemed more repeatable than the Mullen tests in his study.

• 한국염색가공학회지
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• 제13권3호
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• pp.165-171
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• 2001

In this study, UV/vis. spectra of color solution extracted from onion shell and dyeing properties of polyamide fibers such as wool, silk, and nylon were investigated. Also, the effect of mordanting on wash fastness and light fastness was Investigated. The amount of colors extracted was increased with extracting temperature and time. The wavelength of maximum absorption of onion shell extract corresponds to flavonol peak and quercetin peak. Also, spectra of color solution were shifted to longer wavelength at higher pH values. It appeared that the optimum condition of the dyeing of wool, nylon, and silk fabrics with onion shell extract was $60^\circ{C}$ , 30min, and pH 4.0 of dyed bath. Surface colors of the dyed fabrics were different according to the used mordants: Al and Cr mordanted fabrics were dyed in yellowish colors, Cu mordanted fabric in greenish color, Sn mordanted fabric in orange color, and Fe mordanted fabric in khaki color. The mordanting was effective at improving wash fastness and light fastness.

• 복식
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• 제58권4호
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• pp.26-34
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• 2008

The purpose of this study was to create a database of information on the mechanical properties of two different waterproof and breathable shell fabric groups(high density woven and PTFE laminate) used for outdoor apparel and to compare and correlate data of their mechanical properties and hand values. The results of this study were as follows; There were no statistically significant differences between two fabric groups in extension, bending and shearing properties. There were statistically significant differences between two fabric groups in MMD, SMD, LC and we values. High density woven fabrics had smoother surface than PTFE laminated fabrics. PTFE laminated fabrics can be compressed easily more than high density woven fabrics but their recovery after compression was not better than high density woven fabrics. There were statistically significant differences between two fabric groups in NUMERI, FUKURAMI. There was statistically significant difference between two fabric groups in total hand value. Total hand value and mean deviation of MIU had a very high and statistically significant negative correlation coefficient.

• 한국재료학회지
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• 제29권1호
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• pp.43-51
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• 2019

Nacre of abalone shell features a "brick-and-mortar" microstructure, in which micro-plates of calcium carbonate are bonded by nanometers-thick layers of chitin and proteins. Due to the microstructure and its unique toughening mechanisms, nacre possesses an excellent combination of specific strength, stiffness and toughness. This study deals with the possibility of using nacre fragments obtained from abalone shell for making a bulletproof armor system. A composite plate laminated with abalone shell fragments is made and compression and bend tests are carried out. In addition, a bulletproof test is performed with hybrid armor systems which are composed of an alumina plate, a composite plate, and aramid woven fabric to verify the ballistic performance of nacre. The compressive strength of the composite plate is around 258.3 MPa. The bend strength and modulus of the composite plate decrease according to the plate thickness and are about 149.2 MPa and 50.3 GPa, respectively, for a 4.85 mm thick plate. The hybrid armor system with a planar density of $45.2kg/m^2$, which is composed of an 8 mm thick alumina plate, a 2.4 mm thick composite plate, and 18 layers of aramid woven fabric, satisfy the NIJ Standard 0101.06 : 2008 Armor Type IV. These results show that a composite plate laminated with abalone shell fragments can be used for a bulletproof armor system as an interlayer between ceramic and fabric to decrease the armor system's weight.

• 한국의류산업학회지
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• 제23권1호
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• pp.129-141
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• 2021

This study investigated fabrics, washing and cares, design, pattern, subsidiary materials, and sewing methods with a focus on the functional outers using moisture-permeable waterproof fabric as a shell; in addition, each element was analyzed for differences depending on fabric type. The characteristics of 34 outers were investigated through labels, online product introductions, visual inspection, observations from two experts with more than 30 years experience and wear tests. Moisture-permeable waterproof fabrics used for the outer were classified into two types; in addition, the shell of the high-density fabric and the 2 & 3-layer fabrics had different characteristics. Various fabrics, detailed designs, and three-dimensional patterns suitable for each part of the human body were used to improve functionality. In addition, various subsidiary materials and sewing methods were used to form an organic relationship. The same washing and cares, patterns and subsidiary materials were used regardless of fabric type; however, the fabric type influenced the detailed design and sewing. The outers with high-density fabric had a loose fit, short placket, e-banded cuffs, lock-stitch, and lock-stitch+binding. However, the outer with 2 & 3 layer fabric had a slim fit, hood width adjustment, zippered pockets, cuffs with tab, seamless adhesive sewing such as laminating, lock-stitch+ seam-sealing, and welding.

• 한국항공우주학회지
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• 제47권4호
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• pp.256-265
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• 2019

본 논문에서는 평직물 CFRP로 제작한 직교 격자 쉘의 굽힘 하중에 의한 점진적 손상 연구를 수행하였다. 직교 격자는 복합재 바닥면과 함께 경화하여 제작하였다. 굽힘을 받는 직교 격자 쉘의 점진적 손상 해석은 Hashin-Rotem 파손 기준과 Matzenmiller-Lubliner-Taylor (MLT) 모델으로 비선형 유한요소법을 이용하여 수행하였다. 또한, 직교 격자 쉘에 대한 3점 굽힘 시험을 수행하였으며, 시험 결과와 해석 결과를 비교하였다. 변형률과 변위에 대한 시험과 해석 결과는 유사하게 나타났다. 손상 영역은 점진적 손상 해석으로 예측하였으며, 육안 검사와 초음파 비파괴 검사를 통해 측정한 결과와 비교하였다.