• 제목/요약/키워드: micro hole

검색결과 328건 처리시간 0.032초

마이크로 Deep hole 가공 특성에 관한 연구 (A Study on the characteristic of micro deep hole drilling)

  • 김동우;조명우;이응숙;강재훈;민승기
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2001년도 춘계학술대회 논문집
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    • pp.1064-1067
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    • 2001
  • Micro drilling is used in the production of fuel injection nozzle, watch, camera, air bearing and pinted circuit boards(PCB) are demanded for high precision. Recently industries of precision production require more small hole, high aspect ratio and high speed working for micro deep hole drilling. But the undesirable characteristics of micro drilling is the small signal to noise ratios, wandering motion of drill, high aspect ratio and the increase of cutting force as cutting depth increase. So in this paper to obtain the optimization of cutting condition a study on the characteristics of micro deep hole drilling used Tool dynamometer is proposed.

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미소경 드릴링 머신의 시작과 감시에 관한 연구 (A Study on the Development and the Monitoring of Micro Hole Drilling Machine)

  • 백인환;정우섭
    • Journal of Advanced Marine Engineering and Technology
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    • 제18권4호
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    • pp.62-68
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    • 1994
  • Recently, the trends toward reduction in size and weight of industrial products increased the application of micro hole for manufacturing gadgets of high precision and gave rise to a great deal of interest for micro hole drilling M/C. Quite a few research work is performed on micro drilling on domestic basis compared with the tendency of analyzing cutting mechanism, adaptive control, monitoring of generally available drills of diameter greater than 1mm. This study adresses the design, manufacturing and controlling a micro hole drilling M/C with the overload detection instrument and the step feed mechanism. Controlling and monitoring of the drilling process are acomplished on PC basis for more user interfaces and effectiveness. The test machine of the results of this research shows a good foundation for extending further micro hole machining technique.

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금속 소재의 미세 홀 펀칭 시 전단 파괴 거동 연구 (A Study on Shear Fracture Behavior of Metal in Micro Hole Punching Process)

  • 유준환;임성한;주병윤;오수익
    • 소성∙가공
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    • 제12권4호
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    • pp.314-319
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    • 2003
  • In the micro hole punching, the size and shape of burr and burnish zone are very important factors to evaluate quality of micro holes which depend on punch-die clearance, strain rate, workpiece material and etc. To get micro holes with small burr and wide burnish zone for industrial demands, not only the parametric study but also a study on fracture behavior in shear band are necessary. In this study, 100 $\mu$m, 25 $\mu$m micro holes in diameter were fabricated on brass (Cu63/Zn37) and SUS 316 foils as aspect ratio 1:1, and the characteristics of micro holes was investigated comparing with those of macro holes over several mm by scanning electron microscopic views and section views. Like macro hole, micro hole is also composed of 4 portions, rollover. burnish zone, fracture zone and burr, and it shows similar fracture behavior in shear band. But by high strain rate (10$^2$∼10$^3$s$^{-1}$ ) condition unlike that of macro hole fabrication and by the increment of relative grain size in the direction of the workpiece thickness, fracture zone is not observed.

프리크랙과 微小圓孔材의 크랙成長 下限界條件에 관한 硏究 (A Study on the Threshold Condition of Crack Propagation for Pre-Crack and Micro-Hole Specimens)

  • 송삼홍;윤명진
    • 대한기계학회논문집
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    • 제12권2호
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    • pp.278-285
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    • 1988
  • 본 연구에서는 SM15C재와 SM35C재에 퍼얼라이트, 페라이트 조직의 영향을 배재한 비교적 균질한 조직인 구상화시멘타이트조직과 SM35C재에 실용조직 이면서 비교적 균질한 조직인 마르텐사이트 조직을 만들고, 가공하였다.

미세 홀 펀칭시 전단 파괴 거동 연구 (A Study on Fracture Behavior in Shear Band during Micro Hole Punching Process)

  • 유준환;임성한;주병윤;오수익
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2003년도 춘계학술대회논문집
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    • pp.230-235
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    • 2003
  • In the micro hole punching, the size and shape of burr and burnish zone are very important factors to evaluate quality of micro holes which depend on punch-die clearance, stain rate, workpiece material and etc. To get micro holes with small burr and wide burnish zone for industrial demands, not only the parametric study but also a study on fracture behavior in shear band are necessary. In this study, 100 $\mu\textrm{m}$, 25 $\mu\textrm{m}$ micro holes in diameter were fabricated on brass (Cu63/Zn37) and SUS 316 foils as aspect ratio 1:1, and the characteristics of micro holes was investigated comparing with man holes over several mm by scanning electron microscopic views and section views. Like macro hole, micro hole is also composed of 4 portions, rollover, burnish zone, fracture zone and it shows similar fracture behavior in shear band, but? by high strain rate (10$^2$∼ 10$^3$s$\^$-1/) unlike macro hole fabrication and increment of relative grain size several different results are shown.

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미세 구멍 펀칭 기구 개발 (Development of Micro Punching System)

  • 주병윤;오수익;전병희
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2001년도 춘계학술대회 논문집
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    • pp.213-216
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    • 2001
  • A micro hole punching system was developed and micro holes of 100m in diameter were successfully made on brass sheets of loom in thickness. A micro punch made of tungsten carbide was designed to withstand the punch load, considering the buckling and the bending moment due to possible misalignment error. The punch was fabricated by the grinding process with diamond wheel. The die was designed considering the punch load and fabricated by micro electrodischarge machining process. In this system the stripper is designed to guide punch tip to minimize the possible misalignment. The punch was installed on a vertical stepper and the die was mounted on an X-Y translation unit. The precision motion controller controlled all motions of the micro hole punching system. In this study technical difficulties and solutions in the micro hole punching process were also discussed.

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마이크로 드릴링 M/C에 의한 미세구멍가공특성에 관한 연구 (A Study on the Characteristics of Micro Deep Hole Machining in Micro Drilling Machine)

  • 민승기;이동주;이응숙;강재훈;김동우
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2001년도 춘계학술대회 논문집(한국공작기계학회)
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    • pp.275-280
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    • 2001
  • Recently, the trends of industrial products grow more miniaturization, variety and mass production. Micro drilling which take high precision in cutting work is requested more micro hole and high speed working. Especially, Micro deep hole drilling is becoming more important in a wide spectrum of precision production industries, ranging from the production of automotive fuel injection nozzle, watch and camera parts, medical needles, and thick multi-layered Printed Circuit Boards(PCB) that are demanded for very high density electric circuitry. This paper shows the tool monitoring results of micro drill with tool dynamometer. And additionally, microscope with built-in monitor inspection show the relationship between burr in workpiece and chip form of micro drill machining.

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초단펄스 전해 국부화를 이용한 미세구멍 가공 (Localized Electro-chemical Micro Drilling Using Ultra Short Pulses)

  • 안세현;류시형;최덕기;주종남
    • 한국정밀공학회지
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    • 제20권8호
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    • pp.213-220
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    • 2003
  • By the localization of electro-chemical dissolution region, we succeeded in a few micrometer size hole drilling on stainless steel with the radial machining gap of about 1 ${\mu}{\textrm}{m}$. Tens of nanosecond duration voltage pulses were applied between WC micro-shaft and stainless steel in the 0.1 M $H_2SO_4$ solution. Pt balance electrode was used to drill the high aspect ratio micro-hole without generation of Cr oxide layer on the machined surface. The effects of applied voltage, pulse duration, and pulse period on localization distance were investigated according to machining time. We suggested the taper reduction technique especially brought up on blind-hole machining. High quality micro-holes with 8 ${\mu}m$ diameter with 20 ${\mu}m$ depth and 12 ${\mu}m$ diameter with 100 ${\mu}m$ depth were drilled on 304 stainless steel foil. The various hole shapes were also produced including stepped holes and taper free holes.

微小圓孔 및 微小슬릿材의 疲勞크랙 傳播擧動 (Behavior of Fatigue Crack Propagation of Micro-Hole and Micro-Slit Specimensns - For High-Frequency Heat Treantment Specimens -)

  • 송삼홍;윤명진
    • 대한기계학회논문집
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    • 제10권1호
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    • pp.78-85
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    • 1986
  • 본 연구에서는 결함재의 결함선단에 발생 전파하는 피로거동을 검토하기 위해서 미소원공과 미소슬릿을 가공하고, 이것들의 피로한도를 기준으로 해서 이들 결함의 형상이 피로크랙 전파특성에 미치는 영향을 상세히 고찰하고자 한다.

미세심공드릴 가공에 있어서 Be-Cu 재료의 절삭조건에 관한 연구 (A Study on Cutting Conditions of the Be-Cu Material in Micro Deep Hole Drilling Operation)

  • 김희남;유숙철;이형원;이원영;이종화;이인수
    • 대한안전경영과학회지
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    • 제2권2호
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    • pp.117-126
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    • 2000
  • Recently micro deep hole drilling is required in the whole industry. However, micro deep hole drilling has still much difficulty because of the lack of drill rigidity and the interruption of chip. We treated a micro deep hole(diameter 0.35mm, depth 3mm) used in a connector jack pin. Therefore, a surface roughness is very important. In this paper, we studied on the variation of the surface roughness for cutting conditions during micro deep hole drilling of Be-Cu material. Most of all, we tried to drill on CNC for the realization of automatization.

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