• Proceedings of the KSME Conference
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• 2004.04a
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• pp.410-414
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• 2004

Under longitudinal loading continuous fiber reinforced metal matrix composite(MMC) have interpreted an outstanding performance. However, the applicability of continuous fiber reinforced MMCs is somewhat limited due to their relatively poor transverse properties. Therefore, the transverse properties of MMCs are significantly influenced by the properties of the fiber/matrix interface. In this study, elastic-plastic behavior of transversely loaded unidirectional fiber reinforced metal matrix composites investigated by using elastic-plastic finite element analysis. Different fiber placement(square and hexagon) and fiber volume fractions were studied numerically. The interface was treated as three thin layer (with different properties) with a finite thickness between the fiber and the matrix. The analyses were based on a two-dimensional generalized plane strain model of a cross-section of an unidirectional composite by the ANSYS finite element analysis code.

• Journal of the Korean Society of Industry Convergence
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• v.4 no.3
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• pp.267-273
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• 2001

In this study, the survival rate of fiber is investigated by nozzle size difference in injection/mold sides. The survival rate of fiber is influenced about the nozzle size differ. Also, The mechanical properties of short carbon glass fiber reinforced polypropylene are experimentally measured as functions of fiber volume fraction and nozzle size difference. These mechanical properties are compared with the survival rate of fiber and fiber volume fraction using image analysis after pyrolytic decomposition. The survival rate of fiber as well as fiber volume fraction is influenced by injection processing condition, the used materials, mold conditions and nozzle sides difference, etc, In particular, the survival rate of fiber is great influenced when injection/mold nozzle sides are different more than that of the same. Consequently, the mechanical properties of short carbon/glass fiber reinforced polypropylene arc improved as the nozzle sides are the same in injection mold sides.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.10a
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• pp.79-82
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• 2001

In this research, tile effects of reinforcements type on mechanical properties of MMCs were studied. Six kinds preform were fabricated by using Saffil short fiber, HTZ short fiber, $Al_2O_3$ particle, and SiC particle. MMCs were fabricated by using squeeze casting methods. Various tests were conducted to show the effects of reinforcements type on mechanical properties of MMCs. Tensile and compressive properties of MMCs depend on short fiber, however wear properties depend on particle reinforcement. Generally, properties of fiber/particle hybrid MMCs were excellent than those of MMCs with short fiber.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.5 s.248
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• pp.543-549
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• 2006

The bursting properties under various conditions were investigated to ascertain the optimum conditions to yield the best properties. Fiber aspect ratio (AR: length of fiber/diameter of fiber), interphase condition and fiber content were considered as variables which impact the bursting pressure, bulge constant, torsional rigidity ratio. The bursting pressure of reinforced rubber increases up to 8.73 times compared to the virgin material. The better interphase condition shows the higher bursting pressure at given AR and fiber content. The bulge constant and torsional rigidity highly decrease with increasing AR and better interphase condition at same fiber content. The bulge constant and torsional rigidity reveal the minimum of 11% and 0.6% of the matrix, respectively. The bursted shape after test shows the different patterns between unfilled and reinforced rubbers. The case of virgin rubber shows a radiating shape while that of reinforced rubber shows a fluctuating straight line. Overall, it was found that the fiber AR and interphase condition have an important effect on bursting properties.

• Proceedings of the Korea Concrete Institute Conference
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• 1993.10a
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• pp.150-155
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• 1993

The use of polypropylene fibers in concrete has been widely advertised by the fiber manufacturers. However, the behavior of concrete containing plastic fibers has not been fully understood. The effects of fiber on concrete have been forcused on shrinkage crack control mainly from field observation, and the mechanism and the side effect of fiber such as workability reduction have been neglicted. In this paper, the effect of fiber on workability and shrinkage properties have been studied. The addition of fiber significantly reduce workability and requires additional water to maintain the workability, which causes adversal effects on concrete properties.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.321-327
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• 1996

The result of an experimental study on the mechanical properties of different types of polypropylene fiber reinforced concrete are presented in this paper. This study has been performed to obtain the properties of PFRC such as slump, Vee-Bee time, compressive strength, tensile strength, flexural strength, toughness and resistance to impact. The test variables are fiber content, fiber types, fiber length and W/C ratio. Polypropylene fibers were effective in reinforcing the matrix. A remarkable increase in toughness was observed by the addition of polypropylene fibers.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.2
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• pp.61-66
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• 2010

Corn stalk, one of the most abundant agricultural residue in the world, was examined in this study to use it as an alternative fiber source of wood fiber. In order to find the proper way to utilize corn stalk more efficiently, the morphological properties and the papermaking properties of the, bast fibers and the corn pith, were evaluated respectively. Although the bast fiber fraction showed comparable properties to those for hardwoods in the fiber properties and the papermaking properties, the pith resulted in low brightness and low drainage rate. But the short and flexible fibers in pith fraction led to dense and compact handsheet structure, correspondingly the higher sheet strength. There big differences in properties between bast fiber and pith should be considered for the fully utilization of corn stalk.

• Fibers and Polymers
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• v.6 no.1
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• pp.35-41
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• 2005

Research and development of nano fiber products is very active over the world. Physical characteristics and dyeing properties of nylon 66 nano fiber were investigated in this study. X-ray diffraction, DSC, analysis of amino end group, and water absorption were performed to get information concerning physical properties of nano fiber. Nylon 66 nano fiber was dyed with high molecular mass acid dyes. Effects of dyeing temperature, pH of dyeing solution, and concentration of acid dyes on dyeing properties such as rate of dyeing and the extent of exhaustion, were examined and compared to those of regu­lar fiber. It was found that nano fiber adsorbed acid dyes at lower temperature, got rapidly dyed, and its extents of exhaustion at specific dyeing temperature were higher than regular fiber. It was also observed that nano fiber could adsorb a large amount of acid dye without a significant loss in the extent of exhaustion. Washing fastness of the dyed nano fiber was lower by $1/2\~1$ grade, light fastness by 1 grade than the dyed regular fiber.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.11a
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• pp.77-86
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• 2002

In this study we intended to investigate properties of cement mortar with recycled PET fiber, PE fiber, and PP fiber such as slump flow, compressive strength, tensile strength, and flexural strength. As results of experiment, several properties of specimen with recycled PET fiber were little low comparing those of specimen with PE fiber and PP fiber. But if we see from point of economy and recycle of industrial wastes, it has enough reason to be used. Compressive strength of specimen with recycled PET fiber at 56 days was about 10% higher, but tensile strength and flexural strength were lower than that of no-fiber.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.05a
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• pp.27-30
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• 2006

This study investigated influence of organic fiber type and contents on engineering properties of concrete. Test showed that increase of fiber contents decreased fluidity of fresh concrete and it was even worse in concrete adding cellulose fiber. It is decided that concrete containing more than proper level of fiber should be considered. In addition, concrete adding more fiber, nylon and cellulose, resulted in increase of air content but it was satisfied in aimed value. Bleeding capacity of concrete containing more fiber significantly declined and setting time of that was also slightly retarded. For the properties of strength, both compressive and tensile strength of fiber containing concrete were indicated at similar value to control concrete. However, it is clear that if those concrete containing fiber revised the value of increased air contents at fresh state, the strength value of that would be slightly increased.