• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2621-2625
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• 2007

This study aims at analyzing the flow characteristics of the electromagnetic pump using a linear induction motor (LIM) for transferring molten metals. The flow characteristics of the pump are simulated by magnetohydrodynamic(MHD) program. In this system, the LIM is used for transferring molten metal by electromagnetic force. The molten metal is treated as the secondary part of the LIM. Since the LIM produces an electromagnetic force in the duct, the molten metal can flow from the furnace to the reservoir. The flow characteristics of the pump are analyzed using MHD program for magnetic field of 0.1[T] in duct. In order to prove the analysis, we made a prototype electromagnetic pump using LIM.

• 열처리공학회지
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• 제6권2호
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• pp.98-106
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• 1993

Ultra high carbon steel (Fe-1.4%C) was prepared by means of a high frequency induction furnace. The preferred nucleation site of martensite was observed. The changes of hardness and impact thoughness due to tempering temperatures, and the spheroidization of cementite by controlled -rolling were also studied for the steel. The preferred nucleation site of martensite in the ultra high carbon steel is prior austenite grain boundary. The hardness of the steel is slightly increased up to about $300^{\circ}C$, and then decreased with further tempering temperature. However, the impact energy keeps a almost constant value, independent of the tempering temperature. The spheroidization of cementite is accelerated as the reduction in thickness per rolling pass is increased and the number of the rolling passes becomes greater.

• 대한치과기공학회지
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• 제33권2호
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• pp.137-145
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• 2011

Purpose: To evaluate the accuracy of zirconia copings in terms of clinical verified for the clinical application of CAD/CAM. Methods: Zirconia copings (n=5) were prepared using CAD/CAM system and were sintered using the relevant electrical induction furnace, which uses a 2h sintering program with a maximum temperature of $1500^{\circ}C$. The copings placed at the models and the interval values were measured. Results: The meas interval values between the die and the zirconia copings were $44.14{\mu}m$(A), $44.57{\mu}m$(B), $44.72{\mu}m$(C). 51.05 ${\mu}m$(D). Conclusion: The maximum interval values between the die and the zirconia copings were $51.3{\mu}m$ which is acceptable for clinical use. ${\mu}m$ Proper understanding of the test conditions will help enhancing the accuracy of zirconia coping.

• 한국안전학회지
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• 제25권3호
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• pp.28-33
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• 2010

Ni alloy steel is able to use during long time because of good acid and corrosion resistance. So, it's research has focused on developing the alternative alloy which is economically feasible. Recently, consumption of Kovar steel is gradually increased in field of the jet engine and the gas turbine because of its low thermal expansive characteristics. The specimens of Kovar steel(29%Ni-17%Co) contain 0.00%C, 0.03%C, 0.06%C, 0.10%C and 0.20%C, respectively. Ingots are manufactured by VIM(vacuum induction melting furnace) and then specimens are made by automatic hot rolling after heat treatment. Strength of Kovar steel according to carbon contents is estimated by hardness, tensile and impact test. Hardness of the 0.20%C specimen is more improved approximately 14.4% than one of base metal. Its strength increases 32.4% of a base metal, and its impact energy is also enhance 11.5%.

• 한국정밀공학회지
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• 제10권2호
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• pp.146-153
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• 1993

Thd specimens were melited in high frequency induction furnace. The samples for measurements were prepared by machining cylinder of 9.5mm diameter and 15mm height. These samples were then hot-pressed according to strain rate ( .epsilon. ). These samples were decanned and cut out, and subsequently heat treated at 1000 .deg. C for 4hours. These were investigated for the change of microstructure, domain pattern, X-ray diffraction and magnetic properties. The stress distributions in the specimens during compressing process were calculated by a finite element method program(SPID). The calculated stresses were effective stress( .sigma. $_{eff}$), compressive direction stress( .sigma. $_{z}$), and shear stress( .tau. $_{rz}$ ). These stresses were compared with the experimental data.a.a.

• 소성∙가공
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• 제17권5호
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• pp.356-363
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• 2008

An evaluation system of the thermal properties of exothermic & insulating materials was developed. By measuring the power supply of the induction furnace, the thermal property of exothermic & insulating materials could be evaluated with high reproducibility at elevated temperature of molten steel. The thermal properties of exothermic & insulating materials were affected by mixing condition of raw materials. The effect of main components of exothermic & insulating materials such as metallic aluminum and $Fe_2O_3$ powder on the exothermic and insulating properties was examined. It could be expected to design and develop various exothermic & insulating materials by means of the evaluation system of the thermal properties.

• 한국주조공학회지
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• 제23권3호
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• pp.122-129
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• 2003

The abilities and fading behaviors of 5 different inoculants were evaluated by the thermal analyses of the melts which were held at constant temperature after addition in induction furnace. The silicon content was preserved at the high holding temperature of 1,450${\sim}$1,500$^{\circ}C$, which reduced by oxidation at the low one. The inoculation temperature should be higher to obtain better and reproducible result. The inoculation performance of 1%Ba-Fe-Si was the best on the bases of effect and fading behavior.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.73-76
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• 1999

In this thesis, we fabricate a zero-magnetostrictive amorphous ribbon measure the impeadance effect, and then Investigate possibility as a sensor material. $Co_{72.5}$F $e_{0.5}$M $o_{2}$ $B_{15}$ S $i_{5}$ is used as composition of specimen alloy. We first melt the specimen in high frequency induction furnace and then rapidly quench it by using single roll technique. As the result, we obtain a ribbon where thickness is 12${\mu}{\textrm}{m}$, width is 1mm and length is 93mm. Consequently, it is proved through this study that zero-magnetostrictive amorphous ribbon can be used as an excellent magnetic sensor material.rial.l.

• 자원리싸이클링
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• 제25권4호
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• pp.54-59
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• 2016

전기로 공정에서 슬래그는 Fe를 약 20 ~ 35 wt.% 함유한 채로 슬래그 포트로 배출되어 냉각되고 있다. 슬래그 배출 전에 환원하여 용강으로 회수한다면 제강회수율을 향상할 수 있으며, 슬래그 배출량을 감소할 수 있다. 일반적으로 전기로 공정에서는 슬래그 포밍과 (FetO)의 환원제로 카본계의 환원제가 활용되고 있다. 본 실험은 Metal을 유도용해로에 용해한 후 슬래그와 환원제로 흑연분탄과 저가의 Al dross powder를 Pellet으로 투입하여 (FetO)의 환원 회수와 복인(復燐)에 대한 영향성을 조사하였다. 실험결과 Al dross에 의한 환원 회수율은 흑연분탄에 비해 2.5배 이상의 효과를 나타내었으며, 복인(復燐)에 대한 영향은 50 ppm 이하로 크지 않은 것으로 나타났다.

• 대한심미치과학회지
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• 제25권2호
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• pp.79-87
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• 2016

당일수복 보철물 제작을 위해 디지털 프로세스 사용은 필수적이다. 이러한 디지털 프로세스는 구강스캔, 컴퓨터를 이용한 보철물을 디자인 과정(CAD)과 보철물을 가공하는 과정(CAM)을 포함한다. 지르코니아의 굴곡강도는 900Mpa로 리튬디실리케이트의 400MPa보다 더 단단하지만, 리튬디실리케이트를 이용한 보철물 기공시간이 지르코니아와 비교하여 더 짧기에 당일수복 보철물 제작시 리튬디실리케이트 사용이 선호되었다. 하지만, TZI C 와 LUXEN Enamel 와 같은 새로운 소재의 지르코니아가 출시되고, 새로운 소결방식이 개발되어 지르코니아 기공시간을 단축시킬수 있게 되었고, 높은 투명도의 풀지르코니아 크라운을 짧은 시간 안에 제작할 수 있게 되었다. 이러한 발전은 당일 풀지르코니아 보철수복을 현실로 이끌고 있다.