• Fibers and Polymers
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• 제2권1호
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• pp.144-147
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• 2001

The HVI properites and Mantis single fiber tensile properties were analyzed to evaluate the relationship between fiber and bundle tensile properties. For this study, a new method has been developed for estimating the modulus and toughness of cotton fiber bundles directly from the HVI tenacity-elongation curves. The single fiber tensile properties were shown to be translated well into the bundle tensile properties. The single fiber breaking elongation was found to be the most significant contributing factor to bundle tensile properties. The bundle breaking elongation and toughness were shown to increase as the single fiber breaking elongation increased. The bundle modulus increased as the single fiber breaking elongation and/or standard deviation of single fiber breaking elongation decreased.

• 대한전기학회논문지
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• 제43권4호
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• pp.601-606
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• 1994

This paper describes the effect of elongation on electrical properties and molecular structrue of high density polyethylene. Thin polyethylene films films obtained dy roll elongation after extruded at 220$^{\circ}C$ and elongated to draw rations of 16. Crystallinity of polyethylene films was measured by X-Ray diffraction and electrical properties were estimated by conductivity and TSC(Thermal Simulated Current). It was foung that the crystallinity increases and the electrical conductivity decreases as the elongation increases. The elongation dependence of electrical conductivity may be explained by the trap density. Thus, the control of polymer structure and crystallinity makes its properties better and can be applicated in order to get more active properties.

• 접착 및 계면
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• 제25권1호
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• pp.162-168
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• 2024

The effect of maleinized polybutadiene (MPB) on the mechanical properties of epoxy resins including adhesion strength, elongation and impact peel resistance was investigated in this study, in which MPB is an anhydride-functionalized polybutadiene prepolymer. Different molecular weights (3.1K and 5.6K) of MPB were added to diglycidyl ether bisphenol-A (DEGBA), an epoxy resin, to increase its impact peel strength and elongation. At various loading percent (5, 10, 15, 20 and 25 wt%) of MPB in the epoxy resin, significant improvements of mechanical properties were observed. According to the comparative analysis results, the modified epoxy system with 15 wt% (3.1K) MPB exhibited the highest lap shear strength, about 40% higher than that of neat epoxy. The tensile strength and elongation steadily and simultaneously increased as the loading percent of MPB increased. The impact peel strengths at low (-40℃) and room (23℃) temperatures were substantially improved by MPB incorporation into epoxy resins. Reactive and flexible MPB prepolymer seems to construct strong nano-structured networks with rigid epoxy backbones without sacrificing the tensile and adhesion strengths while increasing impact resistance/toughness and elongation properties. For higher impact peel while maintaining adhesion and tensile strengths, approximately 10-15 wt% MPB loading in epoxy resin was suggested. Consequently, incorporation of functionalized MPB prepolymer into epoxy system is an easy and efficient way for improving some crucial mechanical properties of epoxy resins.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1993년도 춘계학술대회 논문집
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• pp.55-58
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• 1993

In this paper, the relationship between trap properties and the molecular orientation owing to elongation was investigation from TSC, electrical conductivity and X-ray diffraction was investgated. The changes of the stretching direction, from an a-axis orientation(at low elongation) to a c-axis orientation(at high elongation), as the elongation increases. were determined from X-my diffraction patterns. These results suggest that the tendency for a decrease in the trap density at a higher elongation is consistent with a continuous change of the reorientation from the a-axis to the c-axis as the elongation increases.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.223-226
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• 1998

In this paper, we have investigated how morphology and electrical properties in Polyphenylene sulfide(PPS) are changed by uniaxial elongation. XRD pattern shows that interplanar distance and crystallinities are decreased by increasing elongation ratio. Electrical conduction mechanism of PPS is explained as schottky emission from analysis of electrical current. The electrical current is decreased by increasing elongation ratio. The conductivity is changed remarkably above the glass transition temperature around $(82^{\circ}C)$. The band gap of PPS is evaluated as 3.9-4(eV) from the results of photoconductivity. Increarnent of elongation ratio gives us some information about deep trap formation from photocurrent.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.1209-1211
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• 1993

In this paper, the relationship between electrical breakdown properties and the molecular orientation owing to elongation was investigation from electrical conductivity, electrical breakdown strength and X-ray diffraction wag investigated. The changes of the stretching direction, from an a-axis orientation(at high elongation) to a c-axis orientation(at high elongation), as the elongation increases, were determined from X-ray diffraction patterns. These results suggest that the tendency for a decrease in the trap density at a higher elongation is consistent with a continuous change of the reorientation from the a-axis to the c-axis as the elongation increases.

• 열처리공학회지
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• 제3권2호
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• pp.20-31
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• 1990

This investigation has been carried out to make clear the effect of deformation temperature, strain rate and grain size on the tensile properties of 304L stainless steel. Tensile properties of the metastable austenitic 304L steel remarkably influenced by deformation temperature. Tensile strength increased with decreasing deformation temperature and the elongation showed maximum value near $40^{\circ}C$. In order to obtain the high elongation, a large amount of deformation is available in austenite before martensitic transformation and the martensite has to be induced gradually. Tensile strength and elongation increased with decreasing grain size. The temperature representing the maximum elongation shifted to low temperature and the peak width of elongation became broaden with decreasing austenite grain size. The volume fraction of strain induced martensite decreased with decreasing austenite grain size. As the strain rate increase, the temperature representing the maximum elongation value shifted to high temperature and volume fraction of strain induced martensite decreased.

• 패션비즈니스
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• 제17권2호
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• pp.179-196
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• 2013

This research is about the mechanical properties of knit pullover of Shaping and WholeGarment according to structured patterns and form of the armhole. For the study 12 samples are prepared under different conditions and through comparative analysis of each sample's armhole around armpit in basic properties, tensile strength & elongation and residual elongation after repeated extensions, the conclusion is as follows. As a result of comparing basic properties of structured pattern of Shaping and WholeGarment samples, in all structured patterns Shaping samples weighed more. According to the comparative analysis of tensile strength & elongation of Shaping and WholeGarment samples, Machi on both sides of WholeGarment samples showed the highest strength. By comparing outcome of residual elongation by structured pattern of Shaping and WholeGarment samples, both types were observed to have the residual elongation increase in the order of Plain

• 한국전기전자재료학회논문지
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• 제17권8호
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• pp.893-897
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• 2004

In this paper, we studied the mechanical and thermal properties on slice XLPE sheet from 22 kV and 154 kV power cables. Interface structures are XLPE/semiconductor and XLPE/water/semiconductor. We evaluated mechanical property, thermal analysis, moisture analysis. Based on mechanical and thermal properties of the 22 kV XLPE sheet, elongation, mechanical strength, and melting point were evaluated to be 485.48 %, 1.74 kgf/$\textrm{mm}^2$ and $102.48^{\circ}C$, respectively. It was also evaluated from the mechanical and thermal properties of 154 kV XLPE sheet that elongation, mechanical strength, and melting point are 507.81 %, 1.8 kgf/$\textrm{mm}^2$, $106.9^{\circ}C$, respectively. A region shows a rapid increase in tension strength, and B region only shows increase in elongation under 1.0 kgf/$\textrm{mm}^2$, C region shows increase in both elongation and tension strength. Difference of melting point came from the chain of XLPE polymer and the difference of crystallization. Moisture density of semiconductor showed 800 ∼ 1200 ppm before extrude, 14000 ∼24000 ppm after extrude. These values were higher than the moisture density of XLPE (300∼560) ppm.

• Journal of Welding and Joining
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• 제22권1호
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• pp.77-82
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• 2004

The effect of bonding condition on tensile properties of joints diffusion bonded spheroidal graphite cast iron, FCD60 to Cr-Mo steel, SCM 440 was investigated. Diffusion bonding was performed with various temperatures, holding times, pressures and atmospheres. All tensile specimens were fractured at the bonding interface. The tensile strength and elongation was increased with increasing bonding temperature. Especially, tensile strength of joints bonded at 1123K was higher than that of a raw material, FCD60, and tensile strength of joints bonded at 1173K was equal to that of a raw material, SCM440, but elongation of all joints was lower than those of raw materials. There was little the effect of holding time on the tensile properties. In comparison with bonding atmosphere, the difference of tensile strength was not observed, but elongation of joint bonded at vacuum(6.7mPa and 67mPa) was higher than that of Ar gas. Higher the degee of vacuum, elongation increased. Tensile properties of diffusion bonds depended on microstructures of cast iron at the interface and void ratio. Microstructures of cast iron at interface changed with temperature, because decarburizing and interdiffusion at the interface occurs and transformation of austenite-1 ferrite + graphite occurs on the cooling process. The void ratio decreased with increasing temperature, especially, effected on the elongation.