• 제목/요약/키워드: Three-Dimensional Forging Simulation

검색결과 27건 처리시간 0.023초

삼차원 소성가공 공정 시뮬레이션을 위한 지능형 사면체 요소망 자동생성 (AUTOMATED ADAPTIVE TETRAHEDRAL ELEMENT GENERATION FOR THREE-DIMENSIONAL METAL FORMING SIMULATION)

  • 이민철;전만수
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2005년도 춘계학술대회 논문집
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    • pp.203-208
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    • 2005
  • In this paper, an automated adaptive mesh generation scheme, based on an advancing-front-Delaunay method, is developed for finite element simulation of three dimensional bulk metal forming processes. During the simulation, the finite element mesh system is adaptively remeshed whenever the mesh is unacceptable. Several schemes are developed such as curvature compensation scheme to minimize volume loss, optimal smoothing scheme to improve element quality, etc. The presented approach is evaluated and applied to automatic forging simulation in order to demonstrate the effect of the developed schemes.

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고속 타격단조시 발생되는 편심부하의 유한요소해석 (Finite element analysis of eccentric loading in high-velocity impact forging)

  • 유요한;양동열
    • 대한기계학회논문집A
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    • 제21권10호
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    • pp.1589-1597
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    • 1997
  • The high-velocity impact forging process with eccentric loading condition is analyzed using the explicit time integration finite element method. In order to consider the strain hardening, strain rate hardening and thermal softening effects, which are frequently observed in high-velocity deformation phenomena, the Johnson-Cook constitutive model is applied to model the workpiece. It is assumed that the material response of the dies is elastic in the study. As a result of the eccentric loading simulation, it is found that the increase of the eccentric ratio and the allowable tilting angle cause the decrease of the maximum forging load and the blow efficiency, and it is also found that the forging load and the blow efficiency generated in the high-velocity impact forging process with three-dimensional geometry can be obtained efficiently.

배압 성형기술을 이용한 Lock-up Hub의 정형제조 기술에 관한 연구 (A Study on Net-shape Technology of Automotive Lock-up Hub using Cold Back Pressure Forming)

  • 권용철;이정환;이영선
    • 소성∙가공
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    • 제17권2호
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    • pp.124-129
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    • 2008
  • Net shape forging technologies give many effects into the costs and qualities for the finished products. So, the studies to reduce the additional machining amount are very important in forging industry. Specially, there are two main topics in cold forging industry, such as, tool life and precision forging. In this study, new forging technique was proposed to eliminate the machining process for fixing up the length and improve the lead accuracy of gear. The luck-up hub is manufactured through many processes, such as upsetting, piercing and direct extrusion. The gear is formed in direct extrusion process; however, lead accuracy of the gear is over allowance limit. Therefore, the additional sizing process must be added. In this study, process design for closed-die forging of a lock-up hub used for a component of automobile transmission was made using three-dimensional finite element simulations, and the strain distributions and velocity distributions are investigated through the post processor. The rigid-plastic finite-element method for back pressure forging has been used in order to reduce development time and die cost. Using the FEM simulation, we found the optimum value of back pressure. The prototypes of lock-up hub parts were forged into the net-shape. In the experiment, lead precision of tooth are measured by the CCMM(Contact Coordinate Measuring Machine). The dimensional accuracy of forged part was improved up to the 40% when back press was applied.

배압 성형기술을 이용한 Lock-up Hub의 정형제조 기술에 관한 연구 (A study on Net-shape technology of Automotive Lock-up Hub using Cold back pressure forming)

  • 권용철;이정환;이영선
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2007년도 추계학술대회 논문집
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    • pp.173-176
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    • 2007
  • The characteristics of the tool system give many effects into the costs and qualities for the finished components. This study proposes a new method for manufacturing of high manufacturing productivity, production process reduction and low cost through back pressure forming. The Lock-up hub is manufactured through many processes, such as upsetting($1^{st}$ Forming), piercing, direct extrusion($2^{nd}$ Forming), final sizing process($3^{rd}$ Forming). In this study, process design for closed-die forging of a Lock-up hub used for a component of automobile transmission was made using three-dimensional finite element simulations, and the strain distributions and velocity distributions are investigated through the post processor. The rigid-plastic finite-element method for back pressure forging has been used in order to reduce development time and die cost. Using the FEM simulation, we found the optimum value of back pressure. The prototypes of Lock-up hub parts were forged into the net-shape. In the experiment, lead precision of tooth are measured by the CCMM(Contact Coordinate Measuring Machine). The dimensional accuracy of forged part was improved up to the 40% when back press was applied.

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3 차원 프린팅 기술의 열간 체적 성형 공정 적용에 관한 기초 연구 - 예비형상 설계 예 및 열간 금형강으로 적층된 표면 특성 분석 (A Preliminary Study on the Application of Three-Dimensional (3D) Printing Technologies to Hot Bulk Forming Processes - Example of Preform Design and Investigation of Hot-working Tool Steel Deposited Surface)

  • 안동규;김세훈;이호진
    • 한국정밀공학회지
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    • 제31권12호
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    • pp.1093-1100
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    • 2014
  • The goal of this paper is to investigate preliminary the applicability of 3D printing technologies for the development of the hot bulk forming process and die. 3D printing technology based on the plastic material was applied to the preform design of the hot forging process. Plastic hot forging dies were fabricated by Polyjet process for the physical simulation of the workpiece deformation. The feasibility of application of Laser-aided Direct Metal Rapid Tooling (DMT) process to the fabrication of the hot bulk metal forming die was investigated. The SKD61 hot-working tool steel was deposited on the heat treated SKD61 using the DMT process. Fundamental characteristics of SKD 61 hot-working tool steel deposited specimen were examined via hardness and wear experiments as well as the observation of the morphology. Using the results of the examination of fundamental characteristics, the applicability of the DMT process to manufacture hot bulk forming die was discussed.

강소성 유한요소해석에서 Hourglass Control (Hourglass Control in Rigid-Plastic Finite Element Analysis)

  • 강정진;오수익
    • 대한기계학회논문집A
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    • 제20권4호
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    • pp.1290-1300
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    • 1996
  • The finite element method, based on rigid-plastic formulation, is widely used to simulate metal forming processes. In order to improve the computational efficiency of the rigid-plastic FEM, one-point integration is used to evaluate the stiffness matrix with four-node rectangular elements and eight-node brick elements. In order to control the hourglass modes, hourglass strain rate components were introduced and included in the effective strain rate definition, Numerical tests have shown that the proposed one-point integration scheme reduces the stiffness matrix evaluation time without deteriorating the convergence behavior of Newton-Raphson method. Simulations of a ring compression, a plane-strain closed-die forging and the three-dimensional spike forging processes were carried out by using the proposed integration method. The simulation results are compared to those obtained by applying the conventional integraiton method in terms of the solution accuracy and computational efficiency.

오목형 피스톤 조립체의 볼과 소켓의 체결을 위한 점진적 성형공정의 유한요소해석 (Finite Element Analysis of an Incremental Forming Process for Joining the Ball with the Socket of a Concave Piston Assembly)

  • 이민철;엄재근;전만수
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2006년도 춘계학술대회 논문집
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    • pp.353-358
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    • 2006
  • A three-dimensional finite element approach to process analysis and design for joining the socket with the ball by a kind of the rotary forging processes is presented in this paper. The rigid-plastic finite element method is employed and its results are used to reduce the number of process design tryouts. The approach is applied to developing a concave piston assembly for a high pressure hydraulic pump. Experiments show that the developed piston assembly satisfies the quality requirement on geometrical tolerance.

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