• Journal of the East Asian Society of Dietary Life
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• v.11 no.6
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• pp.485-497
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• 2001

For a period of 5 days, the quality of breads with Paecilomyces japonica powder were investigated using chemical, sensory, and mechanical evaluations at $25^{\circ}C$. The result of analysis of chemical properties revealed that the pH value of dough was increased as the amount of Paecilomyces japonica powder increased, but volume of dough and baking loss rate were decreased. Breads with 1% and 2% Paecilomyces japonica powder showed a good overall preference in sensory evaluation. As storing time passed. moisture content, lightness, and redness were decreased in all breads, but yellowness increased. Hardness and gumminess of texture analysis were increased as storing time passed, but springiness decreased. Springiness of the mechanical properties was negatively correlated with pH value of dough and volume of bread, while was positively correlated with volume of dough and baking loss rate. In the analysis of correlation between sensory and mechanical properties showed that hardness of mechanical properties had negative correlation with softness, moistness, and springiness. Cohesiveness of mechanical properties had positive correlation with acceptability.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.10a
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• pp.60-63
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• 2003

Semi-solid forming is the process of stirring alloy during solidification, making the mixture of liquid and solid, solidifying it, reheating it to the solid-liquid coexistent temperature, and then injecting this semi solid slurry into dies. In the semi-solid die casting process, it is very important to find out the correlation of injection condition, microstructure and mechanical properties. Especially, an improper injection condition is the main cause of liquid segregation and non-homogeneous mechanical properties due to the difference of solid fraction according to the position of the products. To ensure the database requisite to the semi-solid die casting product, it is essential to acquire the mechanical properties considering liquid segregation to the injection condition. In this study, the effect of injection condition on liquid segregation, formability, microstructure and mechanical properties in a thin product was investigated.

• The Korean Journal of Ceramics
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• v.3 no.2
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• pp.101-104
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• 1997

Although tribological behavior of Si incorporated DLC films have been intensely investigated, their mechanical properties were not consistent among previous publications. The present work reported the structural change by adding Si, and their effects on the mechanical properties. Si incoporated DLC films were deposited using mixtures of benzene and diluted silane with hydrogen of various volume fractions. We could obtain the films of $X_{si}$ (defined by the Si fraction without considering hydrogen) ranging from 0.01 to 0.21, and found that the mechanical properties of the films changed significantly in the range less than $X_{si}=0.06$. In this range, the hardness and stress increased with Xsi. For higher content of Si, the hardness and stress showed saturated behavior with $X_{si}$. This behavior was discussed in terms of the changes in atomic bond structures.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.04a
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• pp.116-120
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• 2005

In this study, composites with polypropylene(PP) and Jute fiber were prepared by compression molding technique. Generally, hydrophilic jute fibers do not adhere well to PP, which is hydrophobic. Maleic anhydride grafted polypropylene(MAPP) had been widely used as a coupling agent to improve the bonding between ligno-cellulosic fibers and PP. The coupling agent improved the tensile and flexural properties when the mechanical properties were tested by using a UTM. The mechanical properties of natural fiber composites(NFCs) by modified thermoplastics were higher than those of NFCs by unmodified thermoplastics. Fracture surfaces of the composites and the fiber orientations were investigated by scanning electron microscopy. The mechanical performance of NFCs by modified thermoplastics appeared to be improved by the enhanced interface adhesion between the fiber and the matrix.

• Transactions of Materials Processing
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• v.15 no.5 s.86
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• pp.360-365
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• 2006

Carbon nanotubes (CNTs) have been the subject of intensive studies for applications in the fields of nano technologies in recent years due to their superior mechanical, electric, optical and electronic properties. Because of their exceptionally small diameters (${\appros}\;several\;nm$) as well as their high Young's modulus (${\appros}1\;TPa$), tensile strength (${\appros}\;200\;GPa$) and high elongation (10-30%) in addition to a high chemical stability, CNTs are attractive reinforcement materials for light weight and high strength metal matrix composites. Although extensive researches have been performed on the electrical, mechanical and functional properties of CNTs, there are not many successful results on the mechanical properties of CNT dispersed nanocomposites. In this paper, we applied equal channel angular pressing for consolidation of CNT/Cu powder mixtures. We also investigated the hardness and microstructures of CNT/Cu nanocomposites used experimental for metal matrix composites.

• Journal of the Korean Ceramic Society
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• v.42 no.1
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• pp.16-21
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• 2005

The effect of additive composition, using AlN and $Er_{2}O_{3}$ as sintering additives, on the mechanical properties of liquid-phase-sintered, and subsequently annealed SiC ceramics was investigated. The microstructures developed were quantitatively analyzed by image analysis. The average thickness of SiC grains increased with increasing the $Er_{2}O_{3}/(AlN + Er_{2}O_{3})$ ratio in the additives whereas the aspect ratio decreased with increasing the ratio. The mechanical properties versus $Er_{2}O_{3}/(AlN + Er_{2}O_{3})$ ratio curve had a maximum; i.e., there was a small composition range at which optimum mechanical properties were realized. The best results were obtained when the ratio ranged from 0.4 to 0.6. The flexural strength and fracture toughness of the SiC ceramics were $550\~650\;MPa$ and $5.5\~6.5$ MPa${\cdot}m^{1/2}$, respectively.

• Journal of the Korean Ceramic Society
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• v.34 no.5
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• pp.491-499
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• 1997

High flexible lightweight composites containing tobermorite as a main mineral is produced using various amorphous silicates, lime, cement and fibers. Here, Mechanical properties of the composites were studied by observing microstructures of hydrates and fibers. Amorphous silicates having better hydraulicity retarded the crystallization of tobermorite due to better formation of C-S-H gel in water bath curing, but, difficult conversion from C-S-H gel to tobermorite in hydrothermal reaction. In the low molar ratio of CaO/SiO2 (0.67), faster crystalization was observed dued to more impurities such as Al2O3 alkali, resulting in improving mechanical properties due to small crystal size and many contact points. It was identified that a lot of calcium silicate hydates formed at surface of pulps increase bonding strength and the crack-resistance of matrix in the composites, but decrease hardness and compressive strength. The choice of amorpous silicates having better hydraulicity, low CaO/SiO2 adding each fibers bellow about 5% in the raw mixs and lower molding pressure should be needed at improve mechanical properties of composites.

• Laser Solutions
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• v.6 no.2
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• pp.19-26
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• 2003

6061 aluminum alloy sheets were I-square butt welded using a continuous wave Nd:YAC laser. Heat inputs were varied from 54.6 to 80 J/mm for butt welding using different sets of the laser power and the weld speed. I-square butt welds were also made with and without Ar shielding gas. The effect of Ar shielding gas and heat input on the mechanical properties and formability was investigated using Vickers hardness, transverse-weld tensile and bulge test. Porosity on the weld beads and sections and hot crack on the fracture surfaces of transverse-weld tensile test specimens were investigated using optical and scanning electron microscopy The experimental results showed that mechanical properties and formability of 6061 aluminum alloy laser welds were degraded compared to those of base metal. Mechanical properties and formability of 6061 aluminum alloy laser welds were not substantially changed when Ar shielding gas was supplied or heat inputs were varied.

• Journal of Industrial Technology
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• v.35
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• pp.31-34
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• 2015

The purpose of the study was to investigate the mechanical properties (diametral tensile strength, flexural strength, compressive strength, Vickers hardness) of 4 kinds of composit resins; Bis-GMA based composit, Bis-EMA based composit, Bis-GMA/UDMA based composit, and Bis-EMA/UDMA based composit, The composit resin based Bis-GMA showed stronger mechanical properties than Bis-EMA. It was found that the addition of UDMA to both Bis-GMA based composit and Bis-EMA based composit highly improved mechanical properties. However, the mechanical properties of the composit resins prepared in this study were lower than those of the commercialized products in market(Charmfil flow(Denkist), Quadrant flow(CAVEX)), since the composit resins prepared in this study has much lower inorganic filler content of 43wt% comparing with 50~70wt% inorganic filler content of the commercialized products.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.2
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• pp.108-114
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• 1998

Development on the mechanical properties of steel sheet for the automobile body panel is very important in the BAF(Batch annealing furnace) annealing process. Because of the heat treatment method in the BAF, mechanical properties was decided on the heat treatment method of the coil. So, we tested on the development of mechanical properties according to heat treatment method at the annealing furnace using the Ax(H$_2$75%, $N_2$25%) atmospheric gas and the HNx(H$_2$4%, $N_2$96%) atmospheric gas. As a result of several investigations. We confirmed the following characteristics ; mechanical properties was changed under the influence of the annealing cycle, the heat treatment method and the atmospheric gas. And, elongation in the HNx BAF was better than the Ax BAF. Finally, most important thing in the BAF is using of proper annealing cycle in order to get a good quality.