• 제목/요약/키워드: ceramic tool

검색결과 224건 처리시간 0.024초

저순도 알루미나 예비소결체의 절삭유제에 따른 세라믹, CBN, 다이아몬드공구의 가공 특성 평가 (Evaluation of Wet Machining Characteristics of the Presintered Low Purity Alumina with the Ceramic, CBN and Diamond Tools)

  • 이재우
    • 한국정밀공학회지
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    • 제24권2호
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    • pp.33-40
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    • 2007
  • In this study, presintered and full sintered low purity alumina ceramics were machined with various tools to clarify the effect of cutting fluid in machinability. The main conclusions obtained were as follows. When the presintered ceramics were wet machined with sintered diamond tool, the tool wear becomes extremely large, and higher cutting speed can be used than in the case of full sintered ceramics. The productivity of wet cutting with the sintered diamond tool is much higher than that of dry cutting. In the case of the CBN and ceramic tools, the tool wear were smaller at wet cutting than at dry cutting, especially exhibiting considerably larger grooved tool wear in wet cutting with ceramic tool.

세라믹 성형체의 미소구멍 가공 시 다이아몬드 입자 전착 드릴의 공구 수명 예측 모델 (Model for predicting tool life of diamond abrasive micro-drills during micro-drilling of ceramic green bodies)

  • 이학구;이대길
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.593-598
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    • 2003
  • Ceramic plates containing many micro-holes are used in diverse applications such as MCP (Microchannel Plate). catalytic converters, filters, electrical insulators in integrated circuits, and so on. One of the efficient methods for machining many holes in ceramic plates is wet drilling of ceramic green bodies followed by sintering them. Since the strength of ceramic green bodies is much lower than the strength of sintered ceramic plate, ceramic green bodies can be drilled with high feed rate. The axial force during micro-drilling of ceramic green bodies increases rapidly at high feed rate, which induces the crack in workpiece. Therefore, the tool lift of micro-drill with respect to feed rate may be determined by the predicting increase of axial force. In this work, the axial force during micro-drilling was calculated using the chip flow model on the micro-drill tip. from which the tool life of diamond abrasive micro-drill during micro-drilling of ceramic green bodies was calculated.

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세라믹공구와 TiN피복 세라믹 공구의 초기파손에 관한 비교연구 (Comparative Study on the Ceramic and the TiN Coated Ceramic Tools for the Early Fracture)

  • 이명재
    • 한국생산제조학회지
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    • 제7권4호
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    • pp.123-129
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    • 1998
  • Ceramic and CBN tools are available for the difficult-to -cut-materials such as hardened carbon tool steel. stainless steel and etc. Ceramic tools are suitable for continuous turning cut, not for intermittent milling cut. Ceramic tools are likely to be chipped and abruptly broken before the appearance of normal wear in turning. In this study, TiN coated ceramic tools were found to restrain the chipping, breaking and early fracture and to increase the critical cutting velocity owing to TiN coating in PVD method.

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오스템퍼링 처리한 구상흑연주철의 AE신호에 의한 절삭공구 손상의 검출에관한 연구 (Detection of the Cutting Tool's Damage by AE Signals for Austempered Ductile Iron)

  • 전태옥;박흥식;이공영;예규현
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 춘계학술대회 논문집
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    • pp.526-530
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    • 1996
  • In this paper, three different types of commercially tools-P20, NC123K and ceramic-have been used to working austempered ductile iron(ADI). In the austempered condition the materials are hard, strong and difficult to machine. Thus, we selected a optimum tool material among three different types of used tools in machining of austempered ductile iron. It was used acoustic emission(AE) to know cutting characteristic for selected tool and flank wear land of the ceramic too. The obtained results are as follows; (1) The ceramic tool among three different types of tools is the best in machining austempered ductile iron. (2) In case of ceramic tool, the amplitude level of AE signal(AErms) is mainly affected bycutting speed in cutting speed in cutting condition and it is proportioned to cutting speed. (3) There have the relationship of direct proportion between the amplitude level of AE signal and flank wear land of the tool. (4) If it find the value of AErms at each cutting speed, the in-process detection to ceramic tool's wear is possible

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알루미나 세라믹 가소결재의 피삭성 -다이아몬드 및 CBN공구의 절삭 성능- (Machinability of Pre-sintered Alumina Ceramics)

  • 김성청
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 1996년도 춘계학술대회 논문집
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    • pp.41-46
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    • 1996
  • In this study, unsintered and pre-sintered low purity alumina ceramics were machined with various tools to clarify the machinability, optimum tool materials and optimum cutting conditions. The main conclusions obtained were as follows. (1)In the case of dry cutting, the sintered diamond and natural diamond tools exhibit better performance in machining of the ceramic pre-sintered at lower temperature, and the tool lives of both tools in machining the ceramics pre-sintered at high temperature becomes extremely short. (2)The performance of CBN tool becomes better in dry machining of the ceramics pre-sintered at higher temperature. (3)When the pre-sintered ceramics were wet machined with sintered diamond, the tool life becomes considerably long, and higher cutting speed can be used than in the case of the CBN and ceramic tools, the tool lives becomes shorter at wet cutting than at dry cutting, especially exhibiting extremely short tool life in wet cutting with ceramic tool.

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세라믹공구 재료의 피복특성에 관한 연구 (A Study on the Coated Characteristics of Ceramic Tools)

  • 이명제;임홍섭;유봉환
    • 대한기계학회논문집A
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    • 제24권4호
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    • pp.900-906
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    • 2000
  • Ceramic, PCD and CBN tools are available for the difficult-to-cut-materials such as hardened carbon tool steel, stainless steel, Inconel 718 and etc. Ceramic tools are likely to be chipped and abruptly broken before the appearance of normal wear in turning. Ceramic tools are suitable for continuous in turning, not for intermittent in milling. In this study, TiN/TiCN multi-layer coated ceramic tools were found to restrain the chipping, breaking and early fracture and to increase the critical cutting speed owing to TiN/TiCN multi-layer coating in Arc Ion Plating of PVD method.

SiC-$Si_3 N_4$ 세라믹공구를 위한 소결시간과 조성변화의 최적화 (Optimization of the Sintering Time and Composition for SiC-$Si_3 N_4$ Ceramic Tool)

  • 김경재;박준석;이성구;권원태;김영욱
    • 한국공작기계학회논문집
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    • 제10권6호
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    • pp.78-84
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    • 2001
  • In the present study, SiCSi-$Si_3 N_4$-SiC ceramic composites that contained up to 30 wt% of dispersed SiC particles were fabricat-ed cia hot-pressing with an oxynitride glass. The microstructure, the mechanical properties and the cutting performance of resulting ceramic composites were investigated. By fixing the composition as $Si_3 N_4$-20wf%SiC, the effect of sintering time on the microstructure, the mechanical properties and the cutting performance were also investigated. The longer sir-tering time is, the bigger the grain size of SiC is. The fracture toughness(-$K_k$) of the $Si_3 N_4$-SiC ceramic composites increased with the increase of gain size, while the flexural strengthh($\sigma$) decreased. For machining SCM440, the insert with 20wt%r SiC sintered for 8 hours showed the longest tool life while the insert with 20wt% SiC sintered for 12 hours showed the longest tool life for machining gray cast iron.

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TiN 코팅 공구의 절삭저항에 관한 연구 (A Study for Cutting Resistance of TiN Coated Tools)

  • 김광래
    • 한국생산제조학회지
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    • 제9권2호
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    • pp.87-95
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    • 2000
  • By using AIP(Arc Ion Plating) of a physical vapor deposition for the first time in Korea a ceramic tool whose surface is coated single layeredly with TiN is developed. In addition cutting resistance appearing in the process of finishing cut of hardened carbon tool steel STC3 is studied. The principal and radial components of cutting resistance in those cutting conditions appear to be the same or similar and the feed component is relatively small. The feed component is found to be in proportion to cutting width and the radial component in proportion to cutting thickness. Owing to coating the cutting resistance of a TiN coated ceramic tool increas-es compared with that of a general ceramic tool.

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TiN 피복 세라믹공구의 절삭저항에 관한 실험적 연구 (On the Experimental Study about Cutting Resistance of TiN Coated Ceramic Tools)

  • 이명재
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 1999년도 추계학술대회 논문집 - 한국공작기계학회
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    • pp.307-314
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    • 1999
  • By using AIP(Arc Ion Plating) of a physical vapor deposition for the first time in Korea a ceramic tool whose surface is coated single layeredly with TiN is developed. In addition, cutting resistance appearing in the process of finishing cut of hardened carbon tool steel, STC3 is studied. The principal and radial components of cutting resistance in those cutting conditions appear to be the same or similar, and the feed component is relatively small. The feed component is found to be in proportion to cutting width, and the radial component in proportion to cutting thickness. Owing to coating the cutting resistance of a TiN coated ceramic tool increases compared with that of a general ceramic tool.

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탄소공구량에 대한 세라믹공구의 초기파손 특성에 관한 연구 (A Study on the Early Fracture Characteristics of Ceramic Tool for Carbon Tool Steel)

  • 김광래;유봉환
    • 한국정밀공학회지
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    • 제12권6호
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    • pp.112-119
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    • 1995
  • Early fracture and cutting force of ceramic tool for hardened STC3 steel was investigated in this study. It was found that early fracture of ceramic tool was mostly occurred before normal wear was progressed beyond a critical cutting speed and normal wear was performed under the critical cutting speed. The relationships among critical cutting speed, which was a cause of early fracture, suggested cutting cross section, that is, maximum thickness of cut and width of cut, and cutting force were examined. The following conclusions were obtained: (1)Critical cutting speed showed a high value in the case of small maximum thickness of cut and large nose radius, but was not influenced by width of cut, (2)Principal, feed and radial force, respectively, showed the proportional value to constant cutting area, width of cut and maximum thickness of cut orderly, (3)Occurrence of early fracture was dependent upon radial force.

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