• 제목/요약/키워드: Surface finish

검색결과 433건 처리시간 0.028초

PCB 표면처리에 따른 Sn-3.0Ag-0.5Cu 무연솔더 접합부의 in-situ 금속간 화합물 성장 및 Electromigration 특성 분석 (Effects of PCB Surface Finishes on in-situ Intermetallics Growth and Electromigration Characteristics of Sn-3.0Ag-0.5Cu Pb-free Solder Joints)

  • 김성혁;박규태;이병록;김재명;유세훈;박영배
    • 마이크로전자및패키징학회지
    • /
    • 제22권2호
    • /
    • pp.47-53
    • /
    • 2015
  • 인쇄회로기판 솔더 상부 및 하부 접합부의 서로 다른 표면처리 조건에 따른 Sn-3.0Ag-0.5Cu (SAC305) 접합부의 열처리 및 전류 인가에 따른 금속간 화합물 성장거동을 비교하기 위하여 in-situ 미세구조분석 및 electromigration (EM) 수명평가를 실시하였다. 솔더 접합 직후, 상부 접합부의 electroless nickel immersion gold (ENIG) 표면처리에서는 $(Cu,Ni)_6Sn_5$, 하부 접합부의 organic solderability preservative (OSP) 표면처리에서는$ Cu_6Sn_5$, $Cu_3Sn$ 금속간 화합물이 접합 계면에서 생성되었다. EM 수명평가 결과 온도 $130^{\circ}C$, 전류밀도 $5.0{\times}10^3A/cm^2$ 하에서 평균파괴시간이 약 78.7 hrs으로 도출되었고, 하부 OSP 표면처리에서 전자가 솔더로 빠져나가는 부분에서 Cu의 소모에 의한 단락이 주 손상기구로 확인되었다. In-situ 주사전자현미경을 통해 계면 미세구조 분석 결과 상부 접합부 ENIG 표면처리에서 전자의 방향에 따른 미세구조의 큰 차이가 없고 뚜렷한 손상이 관찰되지 않았으나, 하부 접합부 OSP 표면처리의 경우 전자가 솔더로 유입되는 부분에서 빠른 Cu 소모로 인한 보이드 성장이 관찰되었다. 따라서, SAC305무연솔더 접합부에서 ENIG 표면처리가 OSP 표면처리보다 보다 우수한 EM확산방지막 역할을 하여 금속간 화합물 성장을 억제하고 보다 우수한 EM 신뢰성을 보이는 것으로 판단된다.

코로나 방전처리에 의한 폴리에스테르 및 P/C 혼방직물의 복합기능화 가공(II) - 복합 기능화 가공 - (Multi-Functional Finish of Polyester and P/C blend Fabrics by Corona Discharge(II) - Multifunctional finish-)

  • Lee, Bang One;Pak, Pyong Ki;Yeo, Joo Hong;Lee, Hwa Sun
    • 한국염색가공학회지
    • /
    • 제9권3호
    • /
    • pp.1-9
    • /
    • 1997
  • Plasma techniques permit modification of the surface layers of the substrate while maintaining its bulk properties. The use of plasma treatment on textile fibers and fabrics is very limited, however, the limitations, plasma treatments have been used to modify surface properties of textiles. In this study, multifunctional finish was performed by corona discharge technique for surface functionalization. Electron spectroscopy for chemical analysis(ESCA) was used to determine the ratios of carbon, oxygen, nitrogen, and phosphor at a 20$\AA$ sampling depth. K/S value and limiting oxygen index(LOI) value were used to obtain information on the effect of the finished fabrics. The mechanism of the flame retardancy was analyzed by the thermogravimetry-and the residue number. In ESCA, relative N1s intensity increased in case of mixtrure. The flame retardancy of the polyester and polyester/cotton fabrics treated with JA-6034 and JA-6050 was found to be operative mainly in the condensed phase mechanism. The multifunctional finish was better effect for the post treated finish agent.

  • PDF

알루미늄 선삭공정에서 발생되는 음향 신호 특성 (An Investigation of Acoustic Signal Characteristics in Turning of Aluminum)

  • 이창희;김용연
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2007년도 춘계학술대회논문집
    • /
    • pp.457-462
    • /
    • 2007
  • This paper reports on the research which investigates acoustic signals acquired in turning with rough and finish simultaneously. The material is aluminum thin pipe. Two acoustic sensors were set on CNC machine. One was set on the finish bite and the other the rough. Two signals were first analyzed in order to consider how much the acoustic signal from the finish bite was coupled by that from the rough. A simple data collecting system to acquire signals from the finish was then determined because two acoustic signals were little coupled. Second the fundamental experiments were accomplished to study the effects of machine vibration and material state. The signal characteristics due to surface defects were studied from the collected acoustic signal data. The signal analysis was based on real time data, root mean squared average and frequency spectrum by fast fourier transform. As a result, the acoustic signals were made effects by machine condition, material structure. The acoustic signal from the finish bite was closely correlated with surface quality. Two types surface micro defects were then evaluated by the signal characteristics.

  • PDF

건축물 벽체용 문양거푸집 개발을 통한 의장콘크리트의 표면광택 특성 (Properties of Surface Grossing on the Design-Concreat by Developing of Design-Forms for Building Wall)

  • 오중근;공민호;조상영;정근호;정상진;정재영
    • 한국건축시공학회지
    • /
    • 제3권1호
    • /
    • pp.131-138
    • /
    • 2003
  • Contemporary architecture calls for a wide range of surface textures and treatments. A surface compatible with the architect's design may vary from a glass-smooth finish to one requiring special sculptured ornamentation. These surfaces require many different types of form sheathing and lining. The purpose of study is development of new design form and made elaborateness shape. Architecture finish material not used expenses working hours, personnel expenses, architecture finish material cost. After this, building wall apply a variety shape in concrete surface and Easy to used in field.

건축벽체용 의장콘크리트 개발에 관한 기초적 연구 (The Fundamental Study on Development of Design-Concrete used Building Wall)

  • 임현준;정근호;김우재;김성식;정재영
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2002년도 학술논문발표회
    • /
    • pp.27-30
    • /
    • 2002
  • Contemporary architecture calls for a wide range of surface textures and treatments. A surface compatible with the architect's design may vary from a glass-smooth finish to one requiring special sculptured ornamentation. These surfaces require many different types of form sheathing and lining. The purpose of study development new design form and made elaborateness shape. Easy to used in field that architecture finish material not used expect effective reduce of working hours, personnel expenses, architecture finish material, cost. After this, building wall apply a variety shape in concrete surface.

  • PDF

건축물에 적용할 수 있는 문양거푸집 개발을 위한 기초적 연구 (A Fundamental Study for Developing Design Forms Application in Building Constructions)

  • 임현준;김광기;김병천;김우재;정재욱;정상진
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 2001년도 가을 학술발표회 논문집
    • /
    • pp.1053-1058
    • /
    • 2001
  • Contemporary architecture calls for a wide range of surface textures and treatments. A surface compatible with the architect's design may vary from a glass-smooth finish to one requiring special sculptured ornamentation. These surfaces require many different types of form sheathing and lining. Chemical retarders applied to the form surface make It possible to remove surface mortar and expose the aggregate after forms have been removed. Variation in finish may also be achieved by grinding, chiseling, hammering, and sandblasting after the concrete has set. Precast panels as forms or liners may provide the desired surface finish; sometimes a combination several of these techniques is used.

  • PDF

황삭 및 정삭을 고려한 통합형 NURBS 곡면 인터폴레이터 (Integrated NURBS Surface Interpolator Considering Both Rough and Finish Cuts)

  • 구태훈;지성철
    • 대한기계학회논문집A
    • /
    • 제27권11호
    • /
    • pp.1958-1966
    • /
    • 2003
  • Three-axis CNC surface machining entails a series of processes including rough cutting, intermediate cutting and finish cutting for a reference surface defined in CAD/CAM. This study is targeting development of an integrated NURBS surface interpolator that can incorporate rough, intermediate and finish cutting processes. In each process, volume to be removed and cutting condition are different according to the shape of a part to be machined and the reference surface. Accordingly, the proposed NURBS surface interpolator controls motion in real-time optimized for the machining conditions of each process. In this paper, a newly defined set of G-codes is proposed such that NURBS surface machining through CNC is feasible with minimal information on the surface composition. To verify the usefulness of the proposed interpolator, through computer simulations on NURBS surface machining, total machining time, size of required NC data and cutting force variations are compared with the existing method.

문양콘크리트의 광택화를 위한 기초적 성능평가에 관한 실험적 연구 (An Experimental Study for Basic Performance Evaluation According to the Glossing Surface Design Concrete)

  • 김재은;김우상;조상영;김성식;임남기;정상진
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2004년도 학술.기술논문발표회
    • /
    • pp.109-112
    • /
    • 2004
  • Contemporary, architecture calls for a wide range of surface textures and treatments. A surface compatible with the architecture's design may vary from a glass-smooth finish to one requiring special sculptured ornamentation. These surfaces require many different types of form sheathing and lining. The purpose, of study development new design form and made elaborateness shape. Easy to used in field that architecture finish material not used expect effective reduce of working hours, personnel expenses, architecture finish material, cost, through this study, we have figured out the best mix proportion for durability and glossability of glossing exposure concrete.

  • PDF

표면염화물량 산정을 위한 건축마감재별 비래염분 부착율 분석 (Attachment Rate Analysis of Airborne Chlorides by Construction Finish Material to Measure the Amount of Chlorides on the Surface)

  • 조규환;지동헌;정재민;박동천
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2014년도 추계 학술논문 발표대회
    • /
    • pp.57-58
    • /
    • 2014
  • For durability design to protect against chloride-induced corrosion, it is important to estimate the amount of chlorides on the surface. However, it is difficult to estimate the airborne chlorides, a boundary condition, due to the difference between the amount of chlorides attached to a surface of an actual structure and that in the air. Therefore, in this study the attachment rate analysis of airborne chlorides was evaluated for 13 types of finish materials. As a result, despite differences in the amount of airborne chlorides according to the finishing type, it was found that 60 percent of airborne chlorides were attached to mortar, 30 percent were attached to steel, and 25 percent were attached to tiles compared with the amount of chlorides in the air.

  • PDF

STUDY FOR DEVELOPMENT OF AN ADDITIVE FOR SEMI-BRIGHTNESS FINISH FOR NICKEL ELECTOPLATING

  • Han, M.K.;Lee, J.K.
    • 한국표면공학회지
    • /
    • 제32권3호
    • /
    • pp.208-210
    • /
    • 1999
  • A new additive for semi-brightness finish in nickel electroplating, having a quarternary ammonium salt structure, has been developed in this study. The effectiveness of the new additive was tested in laboratory-scale eletroplating tests as well as in a full-scale factory plating line. An examination of the plated surface showed that the new additive is as good as the one produced by the most commonly used additive in the nickel plating industry. The plated surface was examined by SEM, EPMA, and Reflectance Spectroscopy, and was found to be compatible to the one obtained with commercial additives. The new additive has a shelf life comparable with those of other commercially available additives. The additive developed in this study has an excellent potential to be used commercially.

  • PDF