• 대한기계학회논문집A
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• 제21권3호
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• pp.430-438
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• 1997

Deburring and edge finishing technology as the final process of machining operation is required for manufacturing of advanced precise conponents. But, deburring is considered as a difficult problem on going to the high efficient production and automation in the FMS. Removal of burr couldn't have a standard of its definition because of its various shapes, dimensions and properties and mostly depends on manual treatment. Especially, deburring for cross hole inside is very difficult owing to its shape passing through out perpendicular to a main hole. The electrochemical method is suggested as its solution in practical aspect. Therefore, electrochemical deburring technology needs to be developed for the high efficiency and automation of internal deburring in the cross hole. In this study, the new process in the eliminating burr inside cross hole, electrochemical deburring by the wheel electroplated with Cubic-Boron-Nitrade abrasives, is suggested. Its deburring mechanism is described and machining performances is investigated. Also, CBN electroplated wheel is designed and manufactured and then characteristics of electrochemical deburring are investigated through experiments. Overall electrochemical deburring performance against burr inside cross hole is examined in the various power sources such as peak current and direct current.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 춘계학술대회 논문집
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• pp.19-23
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• 1996

Deburring and edge finishing technology as the last process of machining operation is required for manufacturing of advanced procesion components, duburring has treated as a difficult problem on going tothe highefficency, automation in the FMS. Removal of butt with various shapes, dimensions and properties coultn't has a standard and has depended on manual treatment. Especially, deburring for cross hole inside owing to passing through out perpendicular to a main hole is more difficult, the electrolytic method is proper as its solution at practical aspects. Therefore, for the high effciency and automation of intermal deburring in the cross hole, development of electrolytic debutting technology is needed. So, the new process in the burr treatment is supposed. In this study, in the eliminating burr inside cross hole, the principle and machining performances of electrochemical deburring by Cubic-Boron-Nitrade abrasive electroplate wheel are investigated, Design and manufacture of CBN electroplated wheel and analysis of characteristics with electrolytic debutting are achieved. Also deburring efficiency and electrolytic performance for cross hole were examined according to electrolytic current and electrolytic deburring condition corresponding to acquired edge quality was found out.

• 한국세라믹학회지
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• 제34권3호
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• pp.249-256
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• 1997

100-500KHz범위의 주파수전원을 인가하여 발생한 플라즈마를 이용하여 질화붕소(boron nitride)막의 합성시 육방정상(hexagonal phase)과 입방정상(cubic phase)의 생성거동을 관찰하였다. BCl3와 NH3를 붕소와 질소의 공급기체로 선택하였고 Ar과 수소를 carrier기체로 사용하였다. 합성변수로는 플라즈마전원의 전압, 기판의 bias, 합성압력, 기체의 조성, 기판의 온도이었는데, 합성된 박막은 FT-IR결과로부터 육방정과 입방정의 혼합상으로 나타났고, 각 상의 분률은 변수의 크기에 의존하였다. TEM분석결과 육방정으로만 구성된 박막은 비정질상으로 이루어졌으며, 입방정과 육방정의 혼합상의 경우는 비정질기지상에 수십 nanometer크기의 입방정입자가 분산된 구조를 하고 있었다.

• Composites Research
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• 제36권6호
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• pp.435-440
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• 2023

본 연구에서는 기존 사용후핵연료(Spent nuclear fuel) 운반/저장 용기에 사용되는 중성자 흡수용 B₄C/Al 복합소재의 열전도도를 개선하기 위해 탄화붕소(B₄C)와 입방정 질화붕소(cBN)를 동시에 강화재로 사용한 알루미늄(Al) 기지 복합소재를 제조하고 평가를 진행하였다. 이를 위해서 교반주조 공정을 통해 복합재 잉곳을 제조하고 이를 압연하여 중성자 흡수용 소재를 성공적으로 제조하였다. 제조된 소재의 평가를 위해 cBN 첨가에 따른 열전도도와 중성자 흡수능 변화를 관찰하였다. 열전도도 측정 결과, B₄C 단일 입자만을 사용한 복합소재 대비 B₄C, cBN을 함께 사용한 복합소재가 동일 체적률 조건 하에서 약 3%의 열전도도 증가가 발생하는 것을 확인하였으며 중성자 흡수 단면적 계산을 통해 중성자 흡수능이 무시할 수 있는 수준으로 저하가 발생하는 것을 확인하였다. 본 연구의 결과를 바탕으로, 중성자 흡수 소재의 새로운 설계 방안을 제시하고 고성능 운반/저장 용기의 개발에 기여할 수 있을 것으로 기대된다.