• Proceedings of the Korean Fiber Society Conference
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• 2000.04a
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• pp.117-120
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• 2000

• Journal of Technologic Dentistry
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• v.25 no.1
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• pp.21-28
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• 2003

The purpose of this study was to process bio-active glass ceramic composite, reinforced with sapphire fibers, by hot press. Also to study the interface of the matrix and the sapphire fiber, and the mechanical properties. Glass raw materials melted in Pt crucible at 1300$^{\circ}C$ during 3.5 hours. The melt was crushed in ball mill and then crushed material, ground and sieved to $<40{\beta}{\mu}m$. Sapphire fibers cut (30mm) and aligned. Powder and fibers hot pressed. The micrographs show good bonding between the matrix and the fiber and no porosity in the glass matrix. This means ideal fracture phenomena. Glass is fractured before the fiber. This is indication of good fracture strength. EDXS showing aluminum rich phase and crystalline phase. Bright field image of the matrix showing crystalline phase. Also diffraction pattern of TEM showing the crystalline phase and more than one phase. Strength of the samples was determined by 3 point bend testing. Strength of the 10vol% sample was approximately 69MPa, while strength of the control sample is 35MPa. Conclusions through this study as follow: 1. Micrographs show no porosity in the glass matrix and the interface. 2. The interface between the fiber and the glass matrix show no gaps. 3. Fracture of the glass indicates characteristic fiber-matrix separation. 4. Presence of crystalline phase at high processing temperature. 5. Sapphire is compatible with bioactive glass.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.05a
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• pp.263-267
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• 2001

The changes of interfacial properties and microfailure degradation mechanisms of bioabsorbable composites with hydrolysis were investigated using micromechanical test and acoustic emission (AE). As hydrolysis time increased, the tensile strength, the modulus and the elongation of PEA and bioactive glass fibers decreased, whereas those of chitosan fiber changed little. Interfacial shear strength (IFSS) of bioactive glass fiber/poly-L-lactide (PLLA) composite was significantly higher than that two other systems. The decreasing rate of IFSS was the fastest in bioactive glass fiber/PLLA composite, whereas that of chitosan fiber/PLLA composite was the slowest. With increasing hydrolysis time, distribution of AE amplitude was narrow, and AE energy decreased gradually.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.6
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• pp.41-48
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• 2000

The Compression molding process is widely used in the automotive industry to produce parts that are large, thin, light-weight, strong and stiff. Compression molded parts are formed by squeezing a glass fiber reinforced polypropylene sheet, known a glass mat thermoplastic(GMT), between two heated cavity surfaces. In this study, the anisotropic viscosity of the Unidirectional Fiber-Reinforced Plastic Composites is measured using the parallel plastometer and the composites is treated as an incompressible Newtonian fluid. The effects of molding parameter and fiber contents ratio on longitudinal/transverse viscosity are also discussed.

• Composites Research
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• v.14 no.4
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• pp.15-26
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• 2001

Interfacial properties and microfailure degradation mechanisms of the bioabsorbable composites fur implant materials were investigated using micromechanical technique and nondestructive acoustic emission (AE). As hydrolysis time increased, the tensile strength, the modulus and the elongation of poly(ester-amide) (PEA) and bioactive glass fibers decreased, whereas these of chitosan fiber almost did not change. Interfacial shear strength (IFSS) between bioactive glass fiber and poly-L-lactide (PLLA) was much higher than PEA or chitosan fiber/PLLA systems using dual matrix composite (DMC) specimen. The decreasing rate of IFSS was the fastest in bioactive glass fiber/PLLA composites whereas that of chitosan fiber/PLLA composites was the slowest. AE amplitude and AE energy of PEA fiber decreased gradually, and their distributions became narrower than those in the initial state with hydrolysis time. In case of bioactive glass fiber, AE amplitude and AE energy in tensile failure were much higher than in compression. In addition, AE parameters at the initial state were much higher than those after degradation under both tensile and compressive tests. In this work, interfacial properties and microfailure degradation mechanisms can be important factors to control bioabsorbable composite performance.

• Elastomers and Composites
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• v.45 no.1
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• pp.32-39
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• 2010

The mechanical properties of PTFE 100%, PTFT 90% + carbon black 10%, PTFE 85% + glass fiber 15%, PTFE 80% + glass fiber 15% + molybdenum disulfide ($MoS_2$) 5%, PTFE 75% + glass fiber 25%, and PTFE 75% + carbon black 18% + graphite 7% composites were investigated in this study. The differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to examine the heat of fusion(${\Delta}H_f$) and thermal stability of the composites. Also, the wear surface and wear volume of PTFE lip seal were examined using the durability test. Wear surface was observed using scanning electron microscope (SEM). It was found that the hardness, wear resistance and durability were enhanced by adding glass fiber and molybdenum disulfide into pure PTFE, but tensile strength and elongation were decreased. According to the experimental results, the composite (PTFE + 15% glass fiber + 5% molybdenum disulfide) showed the best properties for applying to oil-seal among six types of PTFE composites.

• Journal of Ocean Engineering and Technology
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• v.20 no.2 s.69
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• pp.52-58
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• 2006

The effect of various environmental conditions on the durability of E-glass fiber/vinylester resin composites have been investigated using the tensile test specimen of strand type. It was found that the durability test method performed by the stand type specimen was more convenient and reliable than other conventional test method. The weight gains increased with the immersion time in both water and alkaline solution, and the Weight gains at $50^{\circ}C$. were much bigger than those at $20^{\circ}C$ in both conditions. The tensile strength decreased with the pass of immersion time in all aqueous solution, and the tensile strength at $80^{\circ}C$ in alkaline solution decreased very steeply at beginning of immersion time. The decrement of tensile strength according to the immersion time in various environmental conditions was mainly caused by the degradation of interface and the damage of glass fiber surface.

• Textile Coloration and Finishing
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• v.29 no.4
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• pp.239-246
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• 2017

Recently fiber-reinforced thermoplastic composites have attracted great interest from industry and study because they offer unique properties such as high strength, modulus, impact resistance, corrosion resistance, and damping reduction which are difficult to obtain in single-component materials. The demand for plastics is steadily increasing not only in household goods, packaging materials, but also in high-performance engineering plastic and recycling. As a result, the technology of recycling plastic is also attracting attention. In particular, many paper have studied recycling systems based on recycled thermoplastics. In this paper, properties of Glass Fiber Reinforced Thermoplastic(GFRTP) materials were evaluated using recycled PET for injection molding bicycle frame. The effect on thermal and mechanical properties of recycled PET reinforced glass chop fiber according to fiber cross section and fiber content ratio were studied. And it was compared void volume and torque energy by glass fiber cross section, which is round section and flat section. Mechanical characteristics of resulting in GF/rPET has been increased by increasing fiber contents, than above a certain level did not longer increased. And mechanical properties of flat glass fiber reinforced rPET with low void volume were most excellent.

• Composites Research
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• v.29 no.5
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• pp.293-298
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• 2016

In this paper, Glass Fiber Reinforced Thermoplastic (GFRTP) for automotive headlight source module was fabricated by compounding and injection molding using PPS (Poly Phenylene Sulfide) resin with glass fiber which has three cross section (round type, cocoon type, flat type). Tensile, flexural, impact properties were investigated on effect of cross section, glass fiber contents. And it was observed flatness, dimensional stability, fluidity depending on glass fiber cross section. As a result, flat glass fiber reinforced thermoplastic's mechanical properties were most excellent. Also, dimensional stability and flatness showed better results when using flat glass fiber.

• Journal of Adhesion and Interface
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• v.3 no.2
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• pp.17-29
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• 2002

Interfacial properties and microfailure degradation mechanisms of the bioabsorbable composites for implant materials were investigated using micromechanical technique and measurement of surface wettability. As hydrolysis time increased, the tensile strength, the modulus and the elongation of poly(ester-amide) (PEA) and bioactive glass fibers decreased, whereas those of chitosan fiber almost did not change. Interfacial shear strength (IFSS) between bioactive glass fiber and poly-L-lactide (PLLA) was much higher than PEA or chitosan fiber/PLLA systems using dual matrix composite (DMC) specimen. The decreasing rate of IFSS was the fastest in bioactive glass fiber/PLLA composites whereas that of chitosan fiber/PLLA composites was the slowest. Work of adhesion, $W_a$ between bioactive glass fiber and PLLA was the highest, and the wettability results were consistent with the IFSS. Interfacial properties and microfailure degradation mechanisms can be important factors to control bioabsorbable composite performance.