• The Optical Journal
• /
• s.104
• /
• pp.51-51
• /
• 2006

본 고는 사단법인 일본기계공업연합회 및 일본옵토메카트로닉스협회에서 2003년도 3월에 발행한“옵토메카트로닉스 로드맵 작성 조사연구보고서(정밀가공 및 계측요소기술)”로서 국내 광학산업 발전에 도움이 되고자 한국광학기기협회에서 일부 자료를 번역한 것이다. 3월호의 정밀가공 기술로드맵에 이어 5월호와 7월호에서는 계측요소기술 로드맵을 2회 나누어 게재한다.

• Transactions of Materials Processing
• /
• v.1 no.2
• /
• pp.7-13
• /
• 1992

분말의 압축과 소결책의 단조 공정에서 균일하고 강도 높은 제품을 얻기 위해서는 밀도 및 밀도 분포의 조절이 매우 중요하다. 이 연구에서는 재료의 밀도 변화 특성을 고려할 수 있고, 임계 밀도 이하에서도 적용시킬 수 있는 다공질 재료의 항복조건을 유한요소법에 적용시켜 업셋 단조, 3차원 압흔 공정을 해석하였다.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2007.10a
• /
• pp.368-368
• /
• 2007

• Journal of the Korean Society of Propulsion Engineers
• /
• v.9 no.4
• /
• pp.16-22
• /
• 2005

The flow forming has been used to produce long thin walled tube parts, with reduced forming force and enhanced mechanical and surface quality for a good finished part, compared with other method formed parts. So flow forming technique is used widely in industrial production. Especially spinning and flow forming techniques are used frequently in automotive, aerial, defense industry. In this paper, finite element method analysis of three-roller backward flow forming of a workpiece is carried out to study effects of forming depth and feed rate on forming force. The axial and radial forces on several forming depth and feed rate conditions are obtained.

• Journal of the Korean Society for Precision Engineering
• /
• v.13 no.11
• /
• pp.114-123
• /
• 1996

The major objective of the present paper is to estabilish analytical technique in order to closely understand and analyze the actual shearing process. First of all, isothermal and non-isothermal FE-simulation of the shearing process are carried out using finite element software DEFORM. Based on preliminary simulation using DEFORM, the finite element program to analyze two dimensional shearing process is developed. The ductile fracture criterion and the element kill method are also used to estimate if and where a fracture will occur and to investigate the features of the sheared surface in shearing process. It can be seen that the developed program combined with the ductile fracture criterion and element kill method has enabled the achievement of FE-simulation from initial stage to final stage of shearing process. The effects of punch-die clearance on shearing process are also investigated. In order to verify the effectiveness of the proposed technique the simulation results are compared with the known expermental data. It is found that the results of the present work are in close agreement with the published experimental results.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2001.10a
• /
• pp.63-67
• /
• 2001

근래 가공소재로 폭넓게 활용되고 있는 신소재의 대부분은 난삭재로 분류되고 있으며 난삭재 사공에 대한 연구도 활발하게 진행되고 있다. 난삭성에 영향을 미치는 민감한 요인은 재표특성과 가공요소의 복합성을 들 수 있고, 난삭재의 가공은 재료마다 그 최상요건이나 가공방법이 다르므로 일률적인 취급은 곤란하여 각각의 특성을 정확하게 파악하는 것이 중요하다고 하겠다.

• Transactions of Materials Processing
• /
• v.5 no.1
• /
• pp.37-46
• /
• 1996

Superplastic forming/diffusion bonding (SPF/DB) processes were analyzed using a rigid visco-plastic finite element method. The optimum pressure-time relationship for a target strain rate and thickness distributions were predicted by two-node line elements based on the membrane approximation for plane strain. Material behavior during SPF/DB of the integral structures having complicated shapes was investigated. The tying condition is employed for the analysis of inter-sheet contact problems. A movement of rib structure is successfully predicted during the forming.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.9 no.5
• /
• pp.50-56
• /
• 2010

Meshfree methods show many advantages over finite element method(FEM) in the class of problems for which the remeshing process is inevitable when the conventional FEM used, such as propagating crack problems, large deformation and so on. One of the promising applications of meshfree methods is the adaptive refinement for problems having multi-scale nature. In this study, an adaptive node generation procedure is proposed and several numerical examples are also presented to illustrate the efficiency of proposed method.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1990.04a
• /
• pp.62-66
• /
• 1990

최근 미래지향적 첨단 산업 전반에 걸친 고부가가치 부품의 소재대체로 추진되고 있는 제 3의 소재 화인 세라믹스는 우수한 특성과 다양한 기능성으로 각광을 받고 있는 신소 재이나 고경도와 취성등으로 난삭재에 속한다. 화인 세라믹스는 제조법상 소결 공정을 필수로 하여그 수축현상을 피할 수 없으며, 고정도의 요소 부품화를 위해선 후가공을 필요로한다. 국내에선 일종의 세라믹스인 보석등의 미세구멍 가공등에만 국한되어 사용되어질뿐, 아직 화인 세라믹스의 형상 제거 가공등에는 그 가공법이 거의 적용되어 지지 않고 있는 초음파 가공에 대한 실험적 연구를 수행함으로써, 향후 최적 가공기술을 정립하는데 있어 지침이 되고자 한다.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.14 no.1
• /
• pp.9-14
• /
• 2015

To build a high precision machine tool and increase its productivity, structural analysis needs to be carried out for vibration and stiffness of the machine tools before any detailed design. Therefore, in this paper, static and dynamic analysis is carried out to evaluate 8-axis multi tasking machining beds for automotive power train shafts; then, selection of an appropriate device is made for application to bed design. The results of structural and modal analysis confirmed the structural characteristics of the 8-axis multi tasking machine for automotive power train shaft beds: and the second shape bed is the safest is considered secure.