• Steel and Composite Structures
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• 제44권3호
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• pp.339-351
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• 2022

A mortar-filled rectangular hollow structural section (RHS) can increase a structural section property as well as a compressive buckling capacity of a RHS member. In this study, the tensile performance of newly developed mortar-filled RHS members was experimentally evaluated with various connection details. The major test parameters were the type of end connections, the thickness of cap plates and shear plates, the use of stud bolts, and penetrating bars. The test results showed that the welded T-end connection experienced a brittle weld fracture at the welded connection, whereas the tensile performance of the T-end connection was improved by additional stud bolts inserted into the mortar within the RHS tube. For the end connection using shear plates and penetrating stud bolts, ductile behavior of the RHS tube was achieved after yielding. The penetrating bars increased load carrying capacity of the RHS. Based on the analysis of the load transfer mechanism, the current design code and test results were compared to evaluate the tensile capacity of the RHS tube according to the connection details. Design considerations for the connections of the mortar-filled RHS tubes were also recommended.

• 한국의류학회지
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• 제19권4호
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• pp.671-683
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• 1995

This paper described the changes of mechanical KES values after fusing 4 different (in weave & density) wool face fabrics with 3 different (in weave & extensibility) fusible interlining. The fusing condition was 15$0^{\circ}C$, 4kg.f/cm2 The results of the study were as follows: (1) After fusing, KES mechanical value of B, 2HB, G, 2HGS, WC increased, where as LT, WT werent't changed so much and EM, RT decreased. It means after fusing extensibility and recovery property were decreased and volume and stiffness were increased. (2) Within the limits of this investigation, tensile property seemed to be more influenced by the characteristics of face fabrics, and bending property nil by the effect of adhesive penetration and shear and compression property did by complex of the characteristics of face fabrics and interlining and the effect of adhesive penetration.

• 한국의류산업학회지
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• 제8권3호
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• pp.363-369
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• 2006

In this the study, Lyocell fabrics for blanket were developed to get high value added goods for elder and Infant. Therefore, the purpose of the study was determine the effect of twist per inch on the physical properties of developed fabrics, including compression property and abrasion resistance on the process for making Lyocell combined yarns. For comparison, commonly used cotton blanket was used. The results were as the follows: 1) Dimensional changes of Lyocell fabrics was in -3% which value was pretty stable, and antistatic property was very good with 10V of electric propensity voltage which means there was no static electricity at all. Pilling property of Lyocell fabrics showed 3 grade which was good and air permeability and moisture vapor transmission rate of Lyocell fabrics were higher than those of cotton fabric and keeping warmth rate of Lyocell fabrics was about 50% which means it very warms. 2) Twist per inch of Lyocell combined yarns increased with tensile strength and elongation of Lyocell fabrics. 3) Twist per inch of Lyocell combined yarns increased with decreasing thickness reduction rate and therefore, compression property of those was pretty good. Specially, compression property of Lyocell fabrics made with yarns of 3.9TPI was better than those of cotton fabric. 4) Twist per inch of Lyocell combined yarns increased with abrasion resistance of Lyocell fabrics.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2001년도 추계학술발표대회 논문집
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• pp.83-86
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• 2001

This paper presents an investigation of the contribution of fibers in energy absorption during impact and the effect of resin types on properties of the high strength polyethylene (Spectra-900 PE) composite. In high strength polyethylene fiber, main impact energy absorbing mechanism was tensile breakage and deformation of fiber. Two types of resin were examined : Unsaturated polyester (UP) and Epoxy. Tensile and 3-point bending test have been performed to investigate the changes of mechanical properties. In tensile and flexural testes, the Spectra Composite prepregged with UP showed higher properties than Spectra Composite prepregged with epoxy.

• 열처리공학회지
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• 제6권2호
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• pp.49-58
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• 1993

Isothermal transformation behavior during patenting and variations of microstructure and tensile strength of patented wires were investigated in Si-added high carbon steel. The TTT curves of the steels were made for two different austenitizing temperature. As the salt bath temperature was increased, the observed microstructures were bainite at $450^{\circ}C$, the mixture of bainite and pearlite at $500^{\circ}C$, and to pearlite at $600^{\circ}C$, The tensile strength of patented wire exhibited the highest value when the structure was pearlite. while the bainitic structure showed the lowest.

• 한국재료학회지
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• 제17권1호
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• pp.37-42
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• 2007

The effects of immersion time in the liquid nitrogen and deformation-induced martensitic transformation on the behavior of austenite stainless steels used for the hydrogen storage tank of auto-mobile at cryogenic temperature were investigated. With increasing of immersion time in the liquid nitrogen, the tensile strength of all austenite stainless steels at cryogenic temperature was increased because the martensite transformation of unstable austenite. The restraint of crack generation ana transmission also increased the tensile strength by the active ${\alpha}'$ transformation. The elongation decreasing of 321 steel is not the mechanical deformation of austenite phase but the stress induced martensite phase during the tensile test.

• 한국자동차공학회논문집
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• 제2권2호
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• pp.95-102
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• 1994

Aluminum sheet application to automobile body panels has now become an important objective to meet the requirements of automobile weight reduction. As the Mg content in Al-Mg based alloys increased up to 7.19%, the strength and elongation increased. For instance. Al-7.19Mg alloy had a high strength of 305MPa and a high elongation of 35%. A study was also made to investigate the interrelation between grain size and tensile properties with varying the contents of Mg, Ti and Zr elements and annealing conditions. The yield stress decreased as the grain size increased, which increased the uniform elongation. The strain hardening exponents n increased as the Mg content increased, which depended on the increasing difficulties of the cross slip of dislocation.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 춘계학술대회 논문집
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• pp.178-181
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• 2004

Heat treatment is one of important manufacturing process that determine the quality of the products. Because of a difference of mechanical property by heat treatment, It is necessary to This papers presents flow stress and yield point through tensile test. The goal of this study is to obtain the data of flow stress and yield point at martensite, bainite, ferrite/pearlite phase structure using SCM420, SCr420. The result of tensile test is satisfied and is expected to develop an available FEM analysis.

• Computers and Concrete
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• 제6권2호
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• pp.155-165
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• 2009

Splitting tensile strength (STS) of high-performance concrete (HPC) is one of the important mechanical properties for structural design. This property is related to compressive strength (CS), water/binder (W/B) ratio and concrete age. This paper presents a clustering-based fuzzy model for the prediction of STS based on the CS and (W/B) at a fixed age (28 days). The data driven fuzzy model consists of three main steps: fuzzy clustering, inference system, and prediction. The system can be analyzed directly by the model from measured data. The performance evaluations showed that the fuzzy model is more accurate than the other prediction models concerned.

• Nuclear Engineering and Technology
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• 제52권2호
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• pp.352-359
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• 2020

The effects of hydrogen precipitation on the mechanical properties of Zircaloy-4 and Zirlo alloys were examined with uniaxial tensile tests at room temperature and at 400 ℃ and accompanying microstructural changes in the Zircaloy-4 and Zirlo alloy specimens were discussed. The elastic moduli of Zircaloy-4 and Zirlo alloys decreased with increasing hydrogen concentrations. Yield strengths of both materials tended to decrease gradually. The reductions of yield stress seems to be caused by the dissipation of yield point phenomena shown in stress-strain curves. Ultimate tensile strengths (UTS) of Zircaloy-4 and Zirlo slightly increased at low hydrogen contents, and then decreased when the concentrations exceeded 500 and 700 wppm, respectively. Uniform elongations were stable until 600 wppm and drops to 0% around 1400 wppm at room temperature.