• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.3
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• pp.90-95
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• 2000

Today fiber composite materials are routinely used in such wide applications as ships automobiles aircraft space vehi-cles containers sporting goods and appliances. The current knowledge of machining glass fiber reinforced polyester com-posites unfortunately is inadequate for its optimum utilization in many applications. Therefore This paper deals with drilling characteristic of glass fiber reinforced polyester composites. In the drilling of glass fiber reinforced polyester the quality of the cut surfaces is strongly dependent on the drilling parameters. drilling tests were carried out on glass fiber reinforced polyester using standard HSS tools. The material containing random chopped strand fibers and woven roving was fabricated by hand lay-up The entrance and exit surface of the holes was examined. The cutting force was also mea-sured to analyze the drilling characteristics,.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.377-380
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• 1999

The experimental investigating is mainly focused on the hole machining characteristics of glass fiber reinforced polyester at different surface conditions, cutting conditions and machining methods. The entrance and exit surface holes of the glass fiber reinforced polyester is observed and the surface photographs of drilled holes is showed. The cutting force is also measured.

• Polymer(Korea)
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• v.24 no.4
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• pp.459-468
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• 2000

To improve the mechanical properties of fiber-reinforced polymer matrix composites, laminated composites plates were fabricated using different matrix resins and glass or aramid fibers. The effect of matrix resin system were evaluated by tensile, flexural strength measurements. In the case of surface treated aramid fiber and unsaturated polyester resin composite, maximum flexural properties were observed in the composite prepared from the glass fiber treated with 0.5 wt% silane coupling agents. Vinylester resin composites show the highest tensile properties and isophthalic polyester composites have the highest flexural properties among the unsaturated polyester resin composites studied. The relationship between overlap laminated composites plates and mechanical properties of polymer composites is also investigated in order to improve mechanical properties of glass fiber and unsaturated polyester resin composites.

• Journal of the Korean Society of Safety
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• v.16 no.1
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• pp.88-93
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• 2001

This study discusses frequency analysis based on autoregressive (AR) time series model, and process characterization in orthogonal cutting of a fiber-matrix composite materials. A sparsely distributed idealized composite material, namely a glass reinforced polyester (GFRP) was used as workpiece. Analysis method employs a force sensor and the signals from the sensor are processed using AR time series model. The resulting pattern vectors of AR coefficients are then passed to the feature extraction block. Inside the feature extraction block, only those features that are most sensitive to different types of cutting mechanisms are selected. The experimental correlations between the different chip formation mechanisms and AR model coefficients are established.

• Composites Research
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• v.36 no.1
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• pp.37-41
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• 2023

The treated water inside the ballast electrolytic cell creates a highly alkaline atmosphere due to hydroxide generated at the DSA(Dimension Stable Anode) electrode during electrolysis. In this study, a composite material that can replace the weakness of the PE-coated steel pipe used in the existing ballast pipe was prepared. The test samples are BRE(Basalt fiber reinforced epoxy), BRP(Basalt fiber reinforced unsaturated polyester), GRE(Glass fiber reinforced epoxy), and GRP(Glass fiber reinforced unsaturated polyester). And then it was immersed in NaOH for 720 hours. The friction test of each specimen was conducted. The Friction coefficient analysis according to material friction depth and interfacial adhesion behavior between resin and fiber were analyzed. As a result, the mechanism of interfacial separation between resin and fiber could be analyzed. In the case of the unsaturated polyester resin with low interfacial bonding strength the longer the immersion time in the alkaline solution, the faster the internal deterioration caused by the deterioration that started from the surface, resulting in a decrease in the friction coefficient. It is hoped that this study will help to understand the degradation behavior of composite materials immersed in various chemical solutions such as NaOH, acid, and sodium hypochlorite in the future.

• Journal of the Korean Society of Safety
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• v.16 no.3
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• pp.135-142
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• 2001

This study discusses frequency analysis based on the frequency spectrum and process characterization in orthogonal cutting of Fiber-matrix composite materials. A sparsely distributed idealized composite material, namely a glass reinforced polyester(GFRP) was used as workpiece The present method employs a force sensor and the signals from the sensor are processed using the fast Fourier transform(FFT) technique. The experimental correlations between the different chip formation mechanisms and power spectrum me established. Effects of fiber orientation, cutting parameters and tool geometry on the cutting mechanisms me also discussed.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.3
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• pp.21-27
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• 2016

This study was performed to evaluate engineering properties of carbon and glass fiber reinforced recycled polymer concrete. Fiber reinforced recycled polymer concrete were used recycled aggregate as coarse aggregate, natural aggregate as fine aggregate, $CaCO_3$ as filler, unsaturated polyester resin as binder, and carbon and glass fiber as fibers. The compressive and flexural strength of carbon fiber reinforced recycled polymer concrete were in the range of 68~81.5 MPa and 19.1~21.5 MPa at the curing 7days. Also, the compressive and flexural strength of glass fiber reinforced recycled polymer concrete were in the range of 69.4~85.1 MPa and 19~20.1 MPa at the curing 7days. Abrasion ratio of carbon and glass fiber reinforced recycled polymer concrete were decreased 21.6 % and 11.6 % by fiber content 0.9 %, respectively. After impact resistance test, drop numbers of initial and final fracture were increased with increase of fiber contents. Accordingly, carbon fiber and glass fiber reinforced recycled polymer concrete will greatly improve the hydraulic structures, underground utilities and agricultural structures.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.797-803
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• 2001

The on-line cure monitoring of fiber reinforced thermosetting resin matrix composite material was performed for the better quality and productivity during manufacturing. Since the dissipation factor measured by dielectrometry method is dependent on the degree of cure and temperature of resin, in this study, a new method to obtain the degree of cure during on-line cure monitoring for glass/polyester composites was developed by employing a combination function of the temperature and the dissipation factor. Two sensor signals from a K-type thermocouple and an interdigitated dielectric sensor were processed during curing process under various cure cycles. The DSC (Differential Scanning Calorimetry) data was also used for the reference of degree of cure.

• International Journal of Safety
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• v.3 no.1
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• pp.1-5
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• 2004

This study discusses frequency analysis based on autoregressive (AR) time series model, and the characterization of surface quality in orthogonal cutting of a fiber-matrix composite materials. A sparsely distributed idealized composite material, namely a glass reinforced polyester (GFRP) was used as workpiece. Analysis method employs a force sensor and the signals from the sensor are processed using AR time series model. The experimental correlations between the fiber pull-out and AR model coefficients are then established.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2000.06a
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• pp.52-57
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• 2000

This paper discusses frequency analysis based on frequency spectrum in orthogonal cutting of fiber-matrix composite materials. A glass reinforced polyester (GFRP) was used as workpiece. Analysis method employs a force sensor and the signals from the sensor are processed using a fast Fourier transform (FFT) technique. The experimental correlation between the different chip formation mechanisms and model coefficients are then established. (omitted)