• 원예과학기술지
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• 제16권2호
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• pp.242-243
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• 1998

상사화에 chipping, half-chipping, twin-scaling, coring, scooping 및 notching을 실시하여 번식능력과 1인1일구근처리량을 조사하여 가장 경제적인 인공번식법을 구명하고자 본 실험을 실시하였다. 번식능력의 경우 twin-scaling에 의해 1구당 42.19개의 가장 많은 자구를 얻었고 다음은 half-chipping (23.2개) > chipping(18.2개) > notching(14.3개) 순이었으며, coring과 scooping에 의해서는 평균 1개의 자구를 얻어 전혀 효과적인 인공번식법이 아님이 확인되었다. 이상의 결과에서 twin-scaling의 경우 일시에 많은 개체를 얻을 수 있었으나 하루에 200구 정도 작업이 가능하여 번식작업에 가장 많은 시간이 소요되었고 형성된 자구도 매우 작았다. 그러나 chipping의 경우는 하루에 480구 정도로 다른 인공번식법에 비해 가장 많은량을 작업할 수 있었고 또 자구도 비교적 큰 것을 얻을 수 있었으며, 유일하게 기계화가 가능하므로 가장 경제적인 인공번식법으로 판단되었다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.343-346
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• 2005

This study makes the performance evaluation of water-jet chipping through analysis of ruggedness of chipping surface. The ruggedness is mapped by 3D Laser Scanner and the results are also compared with the chipping surface by mechanical chipping. And the details of in-situ works is investigated for increasing interface adhesion between existing concrete and repairing mortar. Water-jet has good operation efficiency which is up $60m^2$ per hour when the chipping depth is 7cm and also has a large ruggedness about 1.65.

• 비파괴검사학회지
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• 제11권1호
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• pp.31-37
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• 1991

Acoustic emission(AE) signals detected during metal cutting were applied as the experimental test to sensing tool wear and chipping on the NC vertical milling machine. The in-process detection of cutting tool wear including chipping, cracking and fracture has been investigated by means of AE in spite of vibration or noise through intermittent metal cutting, then the following results were obtained 1) When the tool wear is increased suddenly, or the amplitude of AE signals changes largely, it indicates chipping or breaking of the insert tip. 2) It was confirmed that AE signal is highly sensitive to the cutting speed and tool wear. 3) At the early period of cutting, the wear were large and RMS value increased highly by the influence of minute chipping and cracking, etc. Therefore, the above situations should be considered for the time when the tool would be changed.

• 대한기계학회논문집
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• 제16권7호
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• pp.1266-1277
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• 1992

본 연구에서는 공구의 형상과 절삭조건에 따른 공구의 결손형태를 예측하기 위하여 현재 가장 널리 쓰이고 있는 인볼류우트커터의 결손형태를 절삭날의 응력분포 값으로 예측하고 실험에 의하여 검증함과 동시에 기어 절삭실험을 통한 공구 결손의 성장거동을 고찰하였으며, 또한 마멸과 결손이 발생함에 따른 절삭력의 변화와 평형을 관찰하여 상호관련성을 비교함으로써 인볼류우트 기어커터의 초기 결손을 해석적으로 예측하였다.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1999년도 추계학술대회 논문집 - 한국공작기계학회
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• pp.502-506
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• 1999

Recently, the miniature of electric products such as notebook, cellular-phone etc. is apparently appeared, due to the smaller size of the semiconductor chips. As the size of chip gets smaller, the circuit could be easily damaged by the slightest influence, so it is important to control the chipping generation in the process of dicing. This paper deals with chipping of the silicon wafer dicing. The relationships between the dicing force and the wafer chipping are investigated. It is confirmed that the wafer chipping increases as the dicing force increases.

• 오토저널
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• 제8권3호
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• pp.28-36
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• 1986

This study was investigated the feasibility of AE application on in-process detection of tool fracture and chipping. Carbon steel SM45C workpiece with longitudinal slots was turned interruptedly on a lathe. AE RMS signal at tool fracture was observed and also the tangential force and the feed observed at the time of tool fracture, the levels of tangential force and the feed force at the time of fracture decrease considerably. In chipping, high level AE signal was observed but there were no changes of cutting force. Peak AE RMS squared is proportional to the area of tool fracture and resultant force. Fracture model of tool fracture is proposed as $V_{p}$ = $C_{1}$ $E_{1}$F(.DELTA. A)$_{0.5}$ and peak AE RMS shows strong correlation with the fracture parameter F(.DELTA.A)$^{0.5}$.

• 한국정밀공학회지
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• 제17권4호
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• pp.106-113
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• 2000

One of the recent changes in machining technology is rapid application of micro- and high precision grinding processes. A fine groove generation is necessary for the fabrication of optics, electronics and semiconductor parts. Slot grinding is very efficient for the generation of micro ordered groove with hard and brittle materials. In the process of slot grinding, chipping at the sharp edges and microcracks of the ground grooves are inevitable defects. Chipping should be reduced for the improvement of surface integrity. Mechanical contact with diamond grits causes microcracks at the grooves. This damage resides subsurface, and can be the cause of failure of the punch die. This paper deals with chipping generation at the sharp edges, surface integrity of side groove and fracture strength is related to the microcracks in the slot grinding.

• 한국정밀공학회지
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• 제16권1호통권94호
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• pp.18-25
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• 1999

Chipping is an unavoidable phenomenon in the slot grinding process of hard and brittle materials. However, it should be reduced for the improvement of surface integrity in the manufacture of optical and semiconductor components. Electrolytic In-process Dressing (ELID) technique for metal bonded superabrasive grinding wheel has been developed for mirror surface grinding of hard and brittle materials. Electrically dressed wheel surface has sharply exposed abrasives and results in lower grinding force, higher grinding efficiency in grinding. The paper deals with a newly developed method for slot grinding using ELID and was implemented to improve grooved surface quality and decreases chipping size on the edge of the groove. As a result, we accomplished chipping-free grooves and obtained the clear ground surfaces on glass and WC.

• 한국기계가공학회지
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• 제4권1호
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• pp.18-23
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• 2005

This paper reports experimental results on microdrilling process for silicon parts used in semiconductor equipments. An experimental system was developed consisting of a high speed precision machine, microscope system, and project profile instrument. The experimental results indicate that the amount of chipping at the entrance and exit of micro hole decreases as the spindle speed increases up to 18,000 rpm. At higher spindle speed, however, the amount of chipping increases rapidly. The amount of chipping and infeed rate show proportional relationship up to 20 m/min of infeed rate. Beyond that infeed rate, however, sudden increase in the amount of chipping has occurred.

• 타이어
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• 통권81호
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• pp.2-12
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• 1979

요지:특수하게 처리한 Cellulose Fiber를 고무에 배합함으로써 배합고무의 기계적 성질을 향상시킬 수 있다. 즉, 소량의 Cellulose Fiber를 천연고무 또는 합성고무에 배합하여 배합고무의 내절상(Cut)성장, 내 Chipping성을 향상시킬 수 있다.