http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
김홍석(H. S. Kim),김낙현(N. H. Kim),이일환(I. H. Lee),최석탁(S. T. Choi),이영선(Y. S. Lee) 한국소성가공학회 2010 한국소성가공학회 학술대회 논문집 Vol.2010 No.5
The importance and application of helical gears as crucial parts of automobiles have been increased steadily owing to its higher power transferring performance with reduced geometrical limitations compared to spur gears. However, the traditional gear manufacturing methods such as hobbing and deburring require long processing time and expensive machines so that there have been intensive efforts trying to make gears by using forging process. Although forging processes for spur and bevel type gears have been developed as practical level, the manufacturing of helical gears has been still depended on traditional cutting process. Therefore, this paper seeks to develop a cold forging process for a helical gear with the helix angle of 18.4225° and the pitch diameter of 43.4571 ㎜. A cold extrusion process was applied due to the relatively small diameter of the target part and the material deforming behaviors according to die geometries were considered by using CAE analysis. Finally, extrusion experiments were conducted and it was found that the helical gear can be manufactured by the cold extrusion process.
연료전지 분리판의 마이크로 채널 제작을 위한 가변성형공정의 실험적 및 수치적 연구
김홍석(H. S. Kim),심재민(J. M. Shim) 한국소성·가공학회 2012 소성가공 : 한국소성가공학회지 Vol.21 No.8
The fuel cell is a very promising power generation system combining the benefits of extremely low emissions, high efficiency, ease of maintenance and durability. In order to promote the commercialization of fuel cells, a flexible forming process, in which a hyper-elastic rubber is adopted as a medium to transmit forming pressure, is suggested as an efficient and cost effective manufacturing method for fuel cell bipolar plates. In this study, the ability of this flexible forming process to produce the micro channel arrays on metallic bipolar plates was first demonstrated experimentally. Then, a finite element (FE) model was built and validated through comparisons between simulated and experimental results. The effects of key process parameters on the forming performance such as applied load and punch velocity were investigated. As a result, appropriate process parameter values allowing high dimensional accuracy without failure were suggested.
가변직경을 갖는 자동차용 카울크로스바의 복합인발공정 개발
김홍석(H. S. Kim),윤재웅(J. W Youn) 한국소성가공학회 2009 한국소성가공학회 학술대회 논문집 Vol.2009 No.5
Cowl cross bar, a component of automotive cockpit module, has been manufactured by using welding processes of several tube parts with different diameters. However, in order to reduce costs and increase the quality, it is required to develop a new production method to manufacture the cowl cross bar as one-piece. In this study, therefore, eliminating the welding process, tube drawing process which is one of meta forming processes was designed by using combined drawing technique. In addition, the selectable range of area reduction ratio was defined as a design guideline and the designed process sequence was verified by finite element analysis.