• Textile Coloration and Finishing
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• v.27 no.3
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• pp.165-174
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• 2015

To develop automobile parts, the unsaturated polyester based matrix resin(PR)/reinforcement(randomly oriented chopped E-glass fiber, GF) composites were prepared using sheet molding compound(SMC) compression molding. The effects of GF length(0.5, 1.0 1.5 and 2.0inch)/content (15, 20, 25, 30wt%) and number of ply(3, 4 and 5) on the specific gravity and mechanical properties of PR/GF composites were investigated in this study. The optimum length of GF was found to be about 1.0inch for achieving improved mechanical properties(tensile strength and initial modulus). The tensile strength and initial modulus of composites increased with increasing GF content up to 30wt%, which is favorable content range for SMC. The specific gravity, tensile strength/initial modulus, compressive strength/modulus, flexural strength/modulus and shear strength increased with increasing the number of ply up to 5, which is the maximum number of ply range for SMC. The effectiveness of ply number increased in the flexural strength > shear strength > compressive strength > tensile strength.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.6
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• pp.809-818
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• 1999

This study was performed to evaluate the tensile bond strength and modulus of elasticity of three permanent soft denture liners (Molloplast $B^{(R)}$, Ufi Gel $C^{(R)},\;Tokuyama^{(R)}$) before and after thermocycling. And their water sorption were also evaluated. Each soft denture liner was bonded to PMMA denture base resin blocks and the tensile bond strength and modulus of elasticity were measured by using universal testing machine. For the water sorption, weight measured after immersion of sea denture liners in $37{\pm}1^{\circ}C$ water bath for 4 weeks. The results were as follows : 1. Molloplast $B^{(R)}$ had the highest tensile bond strength, while Tokuyama had the lowest tensile bond strength. There was no significant difference between $Tokuyama^{(R)}$ and Molloplast $B^{(R)}$ in the both nonthermocycling and thermocycling. There was significant difference in tensile strength of $Tokuyama^{(R)}$ before and after thermocycling(p<0.05). 2. For the modulus of elasticity, there was no significant difference between Ufi Gel $C^{(R)}\;and\;Tokuyama^{(R)}$ in the both nonthermocycling and thermocycling. There was significant difference in modulus of elasticity of $Tokuyama^{(R)}$ before and after thermocycling(p<0.05). 3 The failure modes of Molloplast $B^{(R)}$ and Ufi Gel $C^{(R)}$ were mainley adhesive type and that of $Tokuyama^{(R)}$ was mainly mixed type in case of nonthermocycling and cohesive type after thermocycling. 4. The water sorption of each soft liners was within ${\pm}2%$ in times (p<0.05) but. there was no significant difference among the soft liners in times.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.7
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• pp.91-98
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• 2009

A reliable tensile test technique for PDP's barrier rib materials was introduced. A tensile specimen was prepared by punching out of green sheet, curing the specimen in a high temperature furnace, attaching sand paper tabs on each grip ends, and then attaching two strain gages for the strain monitoring and specimen alignment. Preliminary tensile tests were successfully done with the specimens made from ZnO-based lead-free green sheet. The specimens cured at 3 different maximum curing temperatures were tested to demonstrate the applicability of the test method. The Young's modulus was 88 ${\pm}$ 4 GPa regardless of the maximum curing temperature. The ultimate tensile strength was decreased with increasing the temperature. The tensile test method proposed in this study was proven to be reliable, useful and easy to estimate the bulk mechanical properties of barrier rib materials.

• Journal of Korean Association for Spatial Structures
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• v.10 no.1
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• pp.51-58
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• 2010

ETFE is the abbreviation of Ethylen Tetra Fluoro Etylene, a sort of colorless and transparent granules. The advantage ETFE film has daylight transmission and chemical the resistance and The thickness of ETFE film is used to from $50{\mu}m$ to $300{\mu}m$ and tensile strength of ETFE film changes from 40MPa to 60MPa and the tensile strain at break can get to about 300-400%. In this paper, ETFE film carried out the tensile proprieties, such as the tensile strain at break, the tensile strength are examined.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.399-402
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• 2007

The classical two dimensional modulus of rupture test was generalized to three dimensions. Using this new method, the biaxial tensile strength can be measured with only one actuator. A circular plate is used in this method unlike a prismatic beam in the classical modulus of rupture test. The stress field in this specimen is isotropic and uniform in a plane paralle1 to the bottom surface of the specimen. The relation between the applied load and the maximum stress is derived analytical1y using Timoshenko's solution. A set of experimental data is presented.

• Computers and Concrete
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• v.12 no.3
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• pp.285-301
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• 2013

This paper concentrates on the results of experimental work on tensile strength of self-compacting concrete (SCC) caused by flexure, which is called rupture modulus. The work focused on concrete mixes having water/binder ratios of 0.35 and 0.45, which contained constant total binder contents of 500 $kg/m^3$ and 400 $kg/m^3$, respectively. The concrete mixes had four different dosages of a superplasticizer based on polycarboxylic with and without silica fume. The percentage of silica fume that replaced cement in this research was 10%. Based upon the experimental results, the existing equations for anticipating the rupture modulus of SCC according to its compressive strength were not exact enough. Therefore, it is decided to use artificial neural networks (ANN) for anticipating the rupture modulus of SCC from its compressive strength and workability. The conclusion was that the multi layer perceptron (MLP) networks could predict the tensile strength in all conditions, but radial basis (RB) networks were not exact enough in some circumstances. On the other hand, RB networks were more users friendly and they converged to the final networks quicker.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.370-376
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• 2001

When an adhesive joint is exposed to high environmental temperature, the tensile load capability of the adhesive joint decreases because the elastic modulus and failure strength of structural adhesive decrease. The thermo-mechanical properties of structural adhesive can be improved by addition of fillers to the adhesive. In this paper, the elastic modulus and failure strength of adhesives as well as the tensile load capability of tubular single lap adhesive joints were experimentally and theoretically investigated with respect to the volume fraction of filler (alumina) and the environmental temperature. Also the tensile modulus of the fille containing epoxy adhesive was predicted using a new equation which considers filler shape, filler content and environmental temperature. The tensile load capability of the adhesive joint was predicted by using the effective strain obtained from the finite element analysis and a new failure model, from which the relation between the bonding length and the crack length was developed with respect to the volume fraction of filler.

• Journal of Power System Engineering
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• v.17 no.5
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• pp.69-77
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• 2013

The purpose of this study is to improve the properties of epoxy resin using the big-sized titanium oxide nanoparticles. The effects of particle weight fraction and shape of sample on the thermal and mechanical properties in titanium oxide reinforced epoxy resin has been investigated. In addition, the effect of particle dispersion situation on the mechanical properties of nanocomposites has been studied. As a result, the Tg was almost same regardless of the content of nanoparticles. Storage modulus increased up to the content of 3wt% particles and then decreased. Tensile strength and modulus of film-shaped sample with 1wt% was higher than the one of pure epoxy, while other composites were not. The tensile strength of dogbone-shaped sample with 1wt% was only higher than the one of pure epoxy, while other composites were lower than the one of pure epoxy. Tensile modulus of dogbone-shaped samples increased with the content of particles.

• Macromolecular Research
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• v.12 no.3
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• pp.293-302
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• 2004

We added surface-modified silica nanoparticles to poly(ethylene 2,6-naphthalate) (PEN) to investigate their effect on the mechanical properties on the PEN nanocomposite material. The torque and total torque values of the composites decreased in the silica nanoparticle composites. The tensile modulus of the composites reinforced with unmodified silica nanoparticles increased upon increasing the silica content, while the tensile strength and elongation decreased accordingly. In contrast, stearic acid-modified, silica nanoparticle reinforced PEN composites exhibited an increase in elongation and a decrease in tensile modulus upon addition of the silica nanoparticles because the stearic acid that had adsorbed onto the surface of the silica nanoparticle in multilayers could act as a plasticizer during melt compounding. Stearic acid modification had a small effect on the crystallization behavior of the composites. We calculated theoretical values of the tensile modulus using the Einstein, Kerner, and Nielsen equations and compared these values with the experimental data obtained from the composites. The parameters calculated using the Nielsen equation and the Nicolais- Narkis model revealed that the interfacial adhesion between silica nanoparticles and the PEN matrix could be improved.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.52-54
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• 2003

Poly(vinyl alcohol) (PVA) obtained by the saponification of poly(vinyl ester) is a linear semicrystalline polymer; these polymers have been widely used as fibers for clothes and industries, binders, films, membranes, medicines for drug delivery system, and cancer cell-killing embolic materials. PVA fibers have high tensile and compressive strength, tensile modulus, and abrasion resistance because of the highest crystalline lattice modulus. (omitted)