• 항공우주시스템공학회지
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• 제15권5호
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• pp.1-7
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• 2021

Ti-6Al-4V 티타늄 합금은 무게 대비 우수한 강도와 고온 강도 특성 때문에 수요가 증가하고 있지만 상온에서 낮은 성형성 때문에 고온으로 성형을 해야 한다. 현재 진행된 고온 성형 연구는 하부 금형을 가열하여 시편을 가열하는 방식이기 때문에 제약이 많다. 기존 고온 성형 방식과 다르게 제품을 국부적으로 가열할 수 있는 고주파 유도가열을 적용한다면 가공의 효율성을 높일 수 있을 것으로 예상된다. 또한 공정 기술 개발 시 신뢰도 높은 해석 기법으로 미리 공정을 시뮬레이션한다면 시간과 비용을 절약할 수 있다. 본 논문에서는 고주파 유도가열을 이용하여 Ti-6Al-4V 합금을 가열하였고 실험 결과와 전자기-열전달 연동 해석 결과를 비교하여 해석의 신뢰도를 판단하였다.

• Composites Research
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• 제33권2호
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• pp.55-60
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• 2020

구조용 일액형 에폭시 접착제에 나노 및 마이크로 크기의 Fe₃O₄ 분말을 첨가하여 유도가열용 접착제를 제조하였고, 제조된 접착제를 이용하여 GFRP 피착재의 두께 및 Fe₃O₄ 분말의 첨가량 변화에 따른 가열 성능을 평가하였다. 실험 결과, 접착제의 승온 거동이 유도 가열로 가열한 경우 오븐경화에 비해 GFRP 피착재의 두께에 영향을 작게 받는 것이 관찰되었으며 접착제 내의 Fe₃O₄ 분말의 함량이 증가할수록 가열 속도와 전단 강도가 증가하는 경향을 나타냈다.

• 한국기계가공학회지
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• 제19권4호
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• pp.79-84
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• 2020

Induction bending via high-frequency heating is widely used for manufacturing pipe and section steel bends. It allows productivity improvement, unit cost reduction, delivery time compliance, and good mechanical properties. The recent increase in high-end vessels and offshore plants has raised the demand for high-frequency bending, which should improve the product quality and reduce the costs by simplifying the fabrication process; therefore, the characteristics and performance of this technique must be studied and proper design technology is required. During hot pipe bending via induction heating, the outward wall thickness of the pipe is thinned due to tensile stress and this thickness reduction cannot exceed 12.5%. This study focused on pipe bends with a bending curvature of 5D and their optimization design; in particular, the conditions that can both improve the productivity of the high-frequency bending process and keep the maximum thickness reduction below 12.5% were determined.

• 한국기계가공학회지
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• 제21권2호
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• pp.87-93
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• 2022

The demand for metal-polymer joining technology have been increasing, especially in the industrial fields of automotive and aerospace, which require the manufacturing of various lightweight parts. Conventional joining processes have technical hurdles on aspects such as thermal degradation, need for chemical surface treatment, or complicated process settings. These issues can be alleviated by employing interlocking structures for the metal-polymer joined interface. In this study, we joined 3D-printed metal and polymer parts, which were featured with 3D-printed interlocking structures at their interface. By using high frequency induction heating, the joined region could be locally heated to reduce the thermal degradation and distortion of polymer parts. In addition, through the adjustment of interface morphologies and compression conditions, the polymer flow could be optimized to completely fill the interlocking grooves on metal parts, thereby achieving high joining strength. This suggests feasible guidelines for manufacturing metal-polymer joined structures involving 3D-printed architectures.

• 한국정밀공학회지
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• 제22권2호
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• pp.139-147
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• 2005

The lubricant impregnated MC nylon has good frictional properties, but its mechanical strength is inferior to steel for the mechanical elements. For the tribological application Nylon as gears, sliding bearings, cam and etc, the steel shafts are fitted in pre-heated nylon cylinder by a process of interference expansion fit and bonded by induction heating method. The joint shear strength of the two materials was measured by a universal test machine. From the study, the adhesive shear strength between these two materials was affected by the factors of the interference between nylon and steel, the size of nylon cylinder, knurl of steel shaft and inducting heating conditions. The most effective jointing conditions were analyzed and decided for the practical application in the industry.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2005년도 전력전자학술대회 논문집
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• pp.466-468
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• 2005

Recently, the demand for the development of high quality and high speed laser printer and efficient power utilizations are required. Among complicate electro-mechanic devices in laser printer, the toner fusing unit consumes above 90[%] of all electrical energy needed for printing devices. Therefore, the development of more effective energy-saving toner fusing process becomes a significant task of much great demand. Generally, there are several way to implement fusing unit, among them this paper present a new hybrid induction heating method. The proposed induction heating method enables to increase coupling coefficient between heating coil and heat roller also to Increase total energy transfer efficiency. Therefore the proposed IH inverter system provide very fast W.U.T.(Warm UP Time), also high efficiency. Through experimental result, the proposed control system is verified.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2010년도 하계학술대회 논문집
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• pp.287-288
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• 2010

The Induction Heating equipment is widely used for steel plate heating in the surface treatment process of steel industries. In the case of thin steel plate, for high efficiency We need the high frequency induction heating equipment more than 100kHz. But it is difficult to realize the high frequency and high power at the same time. That's why most high frequency equipment more than 100kHz has been imported from advanced Manufacturer. This paper will describe the development of 100kHz/5MVA inverter module for 100kHz/20MVA induction heating. We used the LCL resonance topology and ZVS/ZCS switching technology. And we also developed the low loss gate drive board and plate busbar inverter stack. We proved the performance by various experiment.

• 한국정밀공학회지
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• 제33권4호
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• pp.287-293
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• 2016

A monobloc tubular drive shaft is designed to obtain the improved structural safety and the weight reduction of the drive shaft together. The monobloc tubular drive shaft can be manufactured from an incremental hot rotary forging process. The aim of this study was to experimentally determine conditions of an incremental hot rotary forging process for a monobloc tubular drive shaft. Induction heating experiments were performed to estimate a proper heating time of an initial workpiece in an induction heating process. Several incremental hot rotary forging experiments were carried out using a mechanical press with the designed set-up. The step distance and the step angle were chosen as controllable forming parameters. Based on the results of the experiments, the influence of forming parameters on the quality of the forged part was investigated. Finally, a forming map and a proper forming condition of the incremental hot rotary forging process were estimated.

• Advances in Computational Design
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• 제2권4호
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• pp.283-291
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• 2017

High frequency full bridge series resonant inverters have become increasingly popular among power supply designers. One of the most important parameter for a High Frequency Full Bridge Series Resonant Inverter is optimal coil design. The optimal coil designing procedure is not a easy task. This paper deals with the New Approach to Optimal Design Procedure for a Real-time High Frequency Full Bridge Series Resonant Inverter in Induction Heating Equipment devices. A new design to experimental modelling of the physical properties and a practical power input simulation process for the non-sinusoidal input waveform is accepted. The design sensitivity analysis with Levenberg-Marquardt technique is used for the optimal design process. The proposed technique is applied to an Induction Heating Equipment devices model and the result is verified by real-time experiment. The main advantages of this design technique is to achieve more accurate temperature control with a huge amount of power saving.

• 한국산학기술학회논문지
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• 제10권4호
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• pp.740-746
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• 2009

본 논문에서는 공진형 유도가열기를 이용한 2단 직렬 부하형 유도가열 과열증기 발생장치를 제안하였다. 발열방식은 외부의 가열코일로부터 특수 합금 발열체에 비접촉 상태로 전자유도 와전류를 구조체에 흐르게 하였다. 인버터는 풀-브리지 고주파 직렬 부하 공진형 이며, LC 공진 설계에서 부하자체를 인덕터로 선정하여 효율을 최대화 하였다. 개발된 장치는 전자유도가열 발열체와 유체이동에 의한 새로운 열교환 방식으로 일체의 연소과정 없이 기체, 액체 및 증발체 등을 상온에서 고온에 이르기까지 고정도의 가열이 가능하다.