양명학의 지행합일설과 행선지후설 : 주자학의 지행설에 대한 비판을 중심으로

홍원식 한국유교학회 1996 유교사상문화연구 Vol.8 No.-

Fe-Si 전기강판 폐스크랩을 이용한 3원계 Fe-9.8Si-6.0Al 합금의 연자성 특성

홍원식,양형우,박지연,오철민,이우성,김승겸,한상조,심금택,김휘준,Hong, Won Sik,Yang, Hyoung Woo,Park, Ji-Yeon,Oh, Chulmin,Lee, Woo Sung,Kim, Seung Gyeom,Han, Sang Jo,Shim, Geum Taek,Kim, Hwi-Jun 한국마이크로전자및패키징학회 2017 마이크로전자 및 패키징학회지 Vol.24 No.1

Fe-9.8Si-6.0Al mother alloy was manufactured using by Fe-3.5Si recycled scrap and Si powder. And then, soft magnetic alloy powder of $D_{50}$ size and sphere type were prepared by gas atomization process. To obtain the soft magnetic powder of a high aspect ratio, in the first, we conducted the ball milling process for 8 hours. And heat treatment was performed under $650^{\circ}C$, 2 hours and $N_2$ atmosphere condition for reducing the residual stress of the powder. Based on these process, we made around $50{\mu}m$ diameter Fe-9.8Si-6.0Al powder, which morphology and shape was a similar to the commercial Fe-Si-Al powder. Finally, the soft magnetic sheets were prepared by tape casting process using by those powders. The permeability of the tape casting sheet was measured, and we confirmed the possibility of reusing to the soft magnetic materials of Fe-Si electric sheet scrap.

공공성이란 무엇인가? 디지털 시대 방송 정책을 위한 시론

홍원식 한국방송협회 2020 방송문화 Vol.- No.420

무엇이 대학생을 투표하게 하였는가?

홍원식 한국방송학회 2011 한국방송학회 학술대회 논문집 Vol.2011 No.11

Fe-Si 전기강판 폐스크랩을 이용한 연자성 분말 및 테이프 제조기술

홍원식,김상현,박지연,오철민,이우성,김승겸,한상조,심금택,김휘준,Hong, Won Sik,Kim, Sang Hyun,Park, Ji-Yeon,Oh, Chulmin,Lee, Woo Sung,Kim, Seung Gyeom,Han, Sang Jo,Shim, Geum Taek,Kim, Hwi-Jun 한국마이크로전자및패키징학회 2016 마이크로전자 및 패키징학회지 Vol.23 No.2

This study focused on examining the possibility for recycling of Fe-Si electric sheet. We manufactured Fe-6.5Si mother alloy using by Fe-Si electric sheet scrap for transformer core materials. And then, soft magnetic alloy powder which diameter and shape were $45{\sim}150{\mu}m$ and sphere type was prepared by gas atomization process. As we compared to commercial Fe-6.5Si powder, its diameter distribution and microstructure of recycled powder was a similar. To investigate the possibility of reusing the soft magnetic composite sheet for electronics, recycled powder was treated to have a high aspect ratio (AR), and we finally obtained the 65~66 AR and $2.3{\mu}m$ thickness powder. To release the residual stress of powder, heat treatment was conducted under $300{\sim}400^{\circ}C$, $N_2$ gas. And then, soft magnetic sheet was made by tape casting process using by those powders. After the density and permeability of tape was measured, and we confirmed that the recycled Fe-Si electric sheet scrap was possible to reuse the soft magnetic materials of electronics.

한국인의 ‘우리’로서 관계 맺기와 그 철학적 배경

홍원식 동양사회사상학회 2005 사회사상과 문화 Vol.0 No.12

한국인은 ‘나’보다 ‘우리’라는 말을 즐겨 쓴다. 여기에는 한국인이 다른 사람과 관계 맺는 방식의 한 특징이 잘 나타나 있다. 곧 한국인은 다른 사람과 관계 맺을 때 나보다는 우리를 앞세운다. 이러한 한국인의 의식은 유교의 공동체주의적, 특히 유교의 가족 중심적 윤리와 관계가 있으며, 철학적으로 보면 주자학의 리기론理氣論과 긴밀한 관계가 있다. 이렇게 한국인들이 우리를 강조하는 가운데 ‘내’가 없다거나 우리 밖의 사람들에 대해 배타적이라는 비판이 있다. 그러나 주자학의 리기론에서 보면, 관계 속의 나는 존재하며, 또한 좁은 울타리를 넘어 끝없이 나를 넓혀 갈 것을 요구하였다. 오늘날 곳곳에서 공동체가 무너지는 소리가 들리고 있다. 혈연을 바탕으로 하는 가족 공동체마저 심각한 위기를 맞고 있다. 이에 따라 공동체를 다시 세워야 한다는 주장이 들리고 있다. 한국인들은 나보다는 우리라는 말에서 따스함을 느낀다. 여기에는 굳이 나를 주장하거나 남을 배척하려는 마음이 있지 않다. 따스한 공동체를 복원하는 데 한국인들의 이러한 ‘우리’라는 의식은 좋은 밑거름이 될 것이다.

SnCu계 무연솔더의 Ni, P 첨가에 따른 분극거동

홍원식,김광배,김휘성,박성훈 한국재료학회 2005 한국재료학회지 Vol.15 No.8

It is inclined to increase that use of hazardous substances such as lead(Pb), mercury (Hg), cadmium(Cd) etc. are prohibited in the electronics according to environmental friendly policies of an advanced nation for protecting environment of earth. As this reasons, many researches for ensuring the reliability were proceeding in Pb free soldering process. If the flux remains on the PCB(printed circuit board) in the soldering process or the electronics exposed to corrosive environment, it becomes the reasons of breakdown or malfunction of the electronics caused by corrosion. Therefore in this studies we researched the polarization and Tafel properties of Sn40Pb and SnCu system solders based on the electrochemical theory. The experimental polarization curves were measured in distilled ionized water and 1 mole 3.5wt% NaCl electrolyte of 40 ℃, pH 7.5. Ag/AgCl and graphite were utilized by reference and counter electrodes, respectively. To observe the electrochemical reaction, polarization test was conducted from -250 mV to +250 mV. From the polarization curves composed of anodic and cathodic curves, we obtained Tafel slop, reversible electrode potential(ECORR) and exchange current density(ICORR). In these results, we compared the corrosion rate of SnPb and SnCu solders.

PCB의 금속 이온 마이그레이션 현상에 관한 연구

홍원식,강보철,송병석 한국재료학회 2005 한국재료학회지 Vol.15 No.1

Recently a lots of problems have observed in high densified and high integrated electronic components. One of them is ion migration phenomena, which induce the electrical short of electrical circuit. Ion migration phenomena has been observed in the field of exposing the specific environment and using for a long time. This study was evaluated the generation time of ion migration and was investigated properly test method through water drop test and high temperature high humidity test. Also we observed direct causes and confirmed generation mechanism of dendritic growth as we reproduced the ion migration phenomena. We utilized PCB(printed circuit board) having a comb pattern as follows 0.5, 1.0, 2.0 mm pattern distance. Cu, SnPb and Au were electroplated on the comb pattern. 6.5V and 15V were applied in the comb pattern and then we measured the electrical short time causing by ion migration. In these results, we examined a difference of ion migration time depending on pattern materials, applied voltage and pattern spacing of PCB conductor.

SnAgCu계 무연솔더의 전기화학적 반응에 따른 타펠 특성

홍원식,김광배 한국재료학회 2005 한국재료학회지 Vol.15 No.8

Recently European Council(EU) published the RoHS(restriction of the use of certain hazardous substances in electrical and electronic equipment) which is prohibit the use of Pb, Hg, Cd, Cr+6, PBB or PBDE in the electrical and electronic equipments. So EU member States shall ensure that, from 1 July 2006, new electrical and electronic equipment put on the market does not contain 6 hazardous substances. The one of the most important in electronics manufacturing process is soldering. Soldering process use the chemical substances which are applied in fluxing and cleaning processes and it can generate the malfunction of electronics caused by corrosion in the fields conditions. Therefore this study researched on the polarization and Tafel properties of Sn40Pb and Sn3.0Ag0.5Cu(SAC) solder based on the electrochemical theory. We prepared SnPb specimens which was aged in 150℃, 180℃ for 15 minutes and Sn3.0Ag0.5Cu specimens that was aged in 180℃, 220℃ for 10 minutes. Experimental polarization curves were measured in distilled ionized water and 3.5wt%, 1mole NaCl electrolyte of 40℃, pH 7.5. Ag/AgCl and graphite were utilized by reference and counter electrode, respectively. To observe the electrochemical reaction, polarization test was conducted from -250 mV to +250 mV. From the polarization curves that were composed of anodic and cathodic curves, we obtained Tafel slop, reversible electrode potential(ECORR) and exchange current density(ICORR). In these results, corrosion rate for two specimen were compared Sn3.0Ag0.5Cu with SnPb solders

전기적 및 전기화학적 특성 측정을 이용한 전자제품 신뢰성평가

홍원식,오철민,박노창,송병석,정승부,Hong, Won-Sik,Oh, Chul-Min,Park, Noh-Chang,Song, Byung-Suk,Jung, Seung-Boo 대한용접접합학회 2007 대한용접·접합학회지 Vol.25 No.2