• 한국재료학회지
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• 제31권8호
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• pp.433-438
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• 2021

In this study, microstructural characteristics and constituent elements of fiberglass splint and cast are examined using a scanning electron microscope and an energy dispersive X-ray spectrometer. As observed by the scanning electron microscope, fiberglass splint and cast had a porous structure with many bundles of fiberglass textures well assembled. Spaces between bundles of the fiberglass splint are triangular or elliptical shaped and the long-axis diameter is measured at about 1 mm. The thickness of fiber bundles covered with plaster is measured at 600 ㎛ and the diameter of a single strand of fiberglass is up to 10 ㎛. The thickness of the fiberglass bundle of the fiberglass splint is measured at about 700 ㎛. Spaces between bundles are formed in the shape of triangles with gentle edges and long-axis diameter of up to 1.4 mm, which is larger than that of the splint. The thickness of a single strand of fiberglass of the plaster-coated cast is 11.5 ㎛, which is thicker than that of fiberglass of the splint. As a result of analyzing constituent elements of the fiberglass cast and the splint with an energy dispersive X-ray spectrometer, Ca, Si, and Al components are identically detected. This result shows that the fiberglass cast has a smoother surface with hardened plaster than the fiberglass splint. The thickness of the fiberglass bundle and the thickness of a single strand of the fiberglass are also larger than those of the fiberglass splint.

• Journal of the Korean Wood Science and Technology
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• 제44권4호
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• pp.505-514
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• 2016

To study mechanical properties of fiberglass reinforced wood-based composite (FRWC), fiberglass with a diameter of $20{\mu}m$ was selected to prepare test specimens. Mechanical properties of fiberglass reinforced wood-based composite were determined by three-point-bending test while its microstructure was characterizes by scanning electron microscopy (SEM). The results showed that mechanical properties of fiberglass reinforced wood-based composite were superior to that of the wood fiberboard based on the contrasting mechanical curves and the analysis of fracture mechanism. It is believed that the material design with this "sandwich" structure brings a unique buffering capacity of fiberglass into play in the composites. So the specimen did not produce a sudden fracture failure at high level of applied loads because it had a bearing ability. The SEM analysis showed that the working strength of PVAc adhesive was high; under a bearing force, it could properly transfer a load. In addition, glass fiber mesh and wood fiber board combined well.

• 한국임상수의학회지
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• 제13권2호
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• pp.204-207
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• 1996

Fiberglass may be a pulmonary toxin and carcinogen because it imitates asbestos, as do other man-made mineral fibers. A 5-months-old Jind dog was accidentally exposed to fiberglass extensively for 3 months in a site of apartment construction. Canine acute clinical pneumoconiosis caused by fiberglass was diagnosed by history, ezamination of environment, physical examination, and chest x-ray check of patient. The main signs were anorexia, dyspnea, increased irregular opacities and air trapping in lung field of chest x-ray films. Because the fiverglass which is used for several purpose are dangerous for health of animal and human. fiberglass dust must be controlled to minimize the adverse effects of fiberglass in the environment.

• 한국안전학회지
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• 제13권1호
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• pp.147-154
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• 1998

본 연구의 목적은 수공구 손잡이의 재질과 형태가 작업 성능과 소비자 만족도에 미치는 영향을 정량적으로 평가하는데 있다. 본 연구는 삽, 써래, 괭이 등 수공구의 손잡이에 기존의 목재를 사용한 것과 fiberglass를 사용한 것을 인간공학적 척도로 비교 분석하였다. 연구 결과 fiberglass 재질의 홈이 파진 손잡이를 사용한 수공구가 기존의 목재 손잡이를 사용한 수공구보다 약 12% 효율적이며, 소비자의 만족도 면에서도 우수한 것으로 나타났다.

• Restorative Dentistry and Endodontics
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• 제49권2호
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• pp.18.1-18.13
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• 2024

Objectives: This study was conducted to evaluate the mechanical properties of relined and non-relined fiberglass posts when cemented to root canal dentin using a conventional dual-cure resin cement or a self-adhesive resin cement. Materials and Methods: Two types of resin cements were utilized: conventional and self-adhesive. Additionally, 2 cementation protocols were employed, involving relined and non-relined fiberglass posts. In total, 72 bovine incisors were cemented and subjected to push-out bond strength testing (n = 10) followed by failure mode analysis. The cross-sectional microhardness (n = 5) was assessed along the root canal, and interface analyses (n = 3) were conducted using scanning electron microscopy (SEM). Data from the push-out bond strength and cross-sectional microhardness tests were analyzed via 3-way analysis of variance and the Bonferroni post-hoc test (α= 0.05). Results: For non-relined fiberglass posts, conventional resin cement exhibited higher pushout bond strength than self-adhesive cement. Relined fiberglass posts yielded comparable results between the resin cements. Type II failure was the most common failure mode for both resin cements, regardless of cementation protocol. The use of relined fiberglass posts improved the cross-sectional microhardness values for both cements. SEM images revealed voids and bubbles in the incisors with non-relined fiberglass posts. Conclusions: Mechanical properties were impacted by the cementation protocol. Relined fiberglass posts presented the highest push-out bond strength and cross-sectional microhardness values, regardless of the resin cement used (conventional dual-cure or self-adhesive). Conversely, for non-relined fiberglass posts, the conventional dual-cure resin cement yielded superior results to the self-adhesive resin cement.

• 한국가구학회지
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• 제21권5호
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• pp.347-353
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• 2010

This research examined the technical feasibility of composite that had 2- and 3- layers of fiberglass reinforcement to enhance the load carrying capacity of particleboard. Specimens were prepared from commercial particleboard. Results indicated that bending properties, hardness and impact bending energy increased as the number of layers of fiberglass reinforcement increased. The wood screw withdrawal load only decreased at the 3-layer of fiberglass reinforcement. The technique developed by this study may increase an opportunity to use particleboard for structural purposes.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.429-432
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• 2003

MMA-modified fiberglass-reinforced plastic composite pipe was produced by using the binder of MMA-modified unsaturated polyester resin in which low viscosity MMA was added to unsaturated polyester resin. Sixteen specimens were made of polymer mortar and fiberglass-reinforced plastic by the centrifugal method. For these specimens the external strength tests were carried out by taking the core thickness consisting of polymer mortar and the fiberglass content per unit area as experimental variables to figure out the effect of variations of these variables influencing on flexural rigidity that is an important property for the composite pipe. Results of this study are believed to provide the basic data for more economical and practical design of MMA-modified fiberglass-reinforced plastic composite pipe.

• Imaging Science in Dentistry
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• 제50권2호
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• pp.141-151
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• 2020

Purpose: This study aimed to quantify the influence of tooth position within the field-of-view (FOV) on cone-beam computed tomography (CBCT) imaging artifacts' intensity when assessing teeth restored with various intracanal materials. Materials and Methods: Seventy single-rooted teeth were divided into 7 groups (10 teeth per group): NiCr post (NC), AgPd post (AP), metal core fiberglass post (MCFG), fiberglass post (FG), anatomical fiberglass post (AFG), fiberglass post cemented with core build-up cement (FGCo), and anatomical fiberglass post cemented with core build-up cement (AFGCo). All posts were cemented using a regular dual-curing resin cement (Allcem), except FGCo and AFGCo which were cemented with a core build-up dual-curing resin cement (AllcemCore). Each tooth was scanned on a CS9000 in 5 positions within the FOV: a central position, anterior horizontal peripheral, peripheral superior, peripheral inferior, and posterior horizontal peripheral position. Hyperdense, hypodense, remaining teeth areas and ROI areas were quantitatively analyzed using ImageJ software. Results: Posterior horizontal peripheral position increased the intensity of artifacts on FGCo and AFGCo post groups (P<0.05), and specifically the hypodense artifact intensity on FG and AFG post groups (P<0.05). NC and AP groups presented greater intensity of artifacts than any other post groups(P<0.05). Conclusion: Artifact intensity increases in the presence of high atomic number materials and when the object is not centered within the FOV. The impact of positioning within the FOV on artifact was greater for fiberglass posts cemented with core build-up dual-curing cement than for metal posts and fiberglass posts cemented with regular dual-curing cement.

• Journal of the Korean Wood Science and Technology
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• 제35권3호
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• pp.29-35
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• 2007

본 연구는 목재 및 파티클보드의 기계적 성질들을 향상시키기 위해 유리섬유를 VARTM 방법에 의해 보강한 복합소재에 대해 조사하였다. 시편들은 상업용 파티클보드 및 간벌소경재로 생산된 목재로 제작하였다. 시편들은 대조구(control)와 유리섬유로 보강된 목재/파티클보드 사이의 변이를 줄이기 위해 제재목과 파티클보드를 각각 길이 방향으로 둘로 잘라 한쪽은 대조구 시편으로 사용했고, 다른 한쪽은 한 층의 단축방향으로 짠 유리섬유 조방사로 시편의 양면을 보강하였다. 목재 및 파티클보드를 VARTM 방법에 의해 유리섬유로 보강한 복합소재는 기계적인 성질들이 크게 향상되었다.

• Steel and Composite Structures
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• 제35권6호
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• pp.765-777
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• 2020

In the context of classic conical shell formulation, nonlinear forced vibration analysis of truncated conical shells and annular plates made of multi-scale epoxy/CNT/fiberglass composites has been presented. The composite material is reinforced by carbon nanotube (CNT) and also fiberglass for which the material properties are defined according to a 3D Mori-Tanaka micromechanical scheme. By utilizing the Jacobi elliptic functions, the frequency-deflection curves of truncated conical shells and annular plates related to their forced vibrations have been derived. The main focus is to study the influences of CNT amount, fiberglass volume, open angle, fiber angle, truncated distance and force magnitude on forced vibrational behaviors of multi-scale truncated conical shells and annular plates.