• 소성∙가공
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• 제28권3호
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• pp.123-129
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• 2019

Hypereutectic Al-Si alloys have been widely utilized for wear-resistant components in the automotive industry. In order to expand the application of Hypereutectic Al-Si alloys, the addition of alloying elements forming a stable precipitate at high temperature is required. Thermally stable inter metallic compounds can be formed through the addition of transition elements such as Fe, Ni to Al alloys. However, the amount of transition element to be added to Al alloys is limited due to their low solid solubility. Also, hypereutectic Al-Si-Fe alloys form coarse primary Si phases and needle-shaped intermetallic compounds during solidification in the general casting processes. In this study, the effects of the destruction of Intermetallic compound and Si phase are investigated via hot extrusion. Both the microstructure and mechanical properties are discussed under different extrusion conditions.

• 주류산업
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• 제19권1호
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• pp.1-9
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• 1999

• 주류공업
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• 제6권2호
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• pp.32-38
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• 1986

• 주류공업
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• 제8권2호
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• pp.20-29
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• 1988

• 주류산업
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• 제23권3호
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• pp.1-11
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• 2003

• 주류산업
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• 제21권4호
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• pp.1-9
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• 2001

• 주류산업
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• 제33권4호
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• pp.26-29
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• 2013

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2009년도 학술발표대회
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• pp.27-31
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• 2009

• 동력기계공학회지
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• 제17권4호
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• pp.94-102
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• 2013

Manufactured $SiC_f/SiC$ composites by NITE method was investigated fracture characteristics according to the size of the surface crack. Coated surface crack with a $SiO_2$ colloid in several ways was evaluating the possibility of healing. The strength of CCS and UCS is 313 and 230MPa, respectively and it is about 1/3 of the SPS. Bending strength of $SiC_f/SiC$ composites has no effect with the pre-crack size to the critical crack size. $SiC_f/SiC$ composites can not generate large amount of $SiO_2$ oxides to the bottom of crack, and is only generated randomly on surfaces, and can not contribute to the recovery of bending strength.

• Advances in nano research
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• 제2권1호
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• pp.23-56
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• 2014

The significant growth of the Si photovoltaic industry has been so far limited due to the high cost of the Si photovoltaic system. In this regard, the most expensive factors are the intrinsic cost of silicon material and the Si solar cell fabrication processes. Conventional Si solar cells have p-n junctions inside for an efficient extraction of light-generated charge carriers. However, the p-n junction is normally formed through very expensive processes requiring very high temperature (${\sim}1000^{\circ}C$). Therefore, several systems are currently under study to form heterojunctions at low temperatures. Among them, carbon nanotube (CNT)/Si hybrid solar cells are very promising, with power conversion efficiency up to 15%. In these cells, the p-type Si layer is replaced by a semitransparent CNT film deposited at room temperature on the n-doped Si wafer, thus giving rise to an overall reduction of the total Si thickness and to the fabrication of a device with cheaper methods at low temperatures. In particular, the CNT film coating the Si wafer acts as a conductive electrode for charge carrier collection and establishes a built-in voltage for separating photocarriers. Moreover, due to the CNT film optical semitransparency, most of the incoming light is absorbed in Si; thus the efficiency of the CNT/Si device is in principle comparable to that of a conventional Si one. In this paper an overview of several factors at the basis of this device operation and of the suggested improvements to its architecture is given. In addition, still open physical/technological issues are also addressed.