Korean Journal of Rheology, Vol.1, No.1, 36-45, November, 1989
유한요소법을 이용한 다단식 아이어닝공정의 유동특성에 관한 연구
A Study on the Flow Behaviors of the Multi-Pass Ironing process by the Finite Element Method
초록
아이어닝 공정은 제품의 치수정밀도가 정확하게 조절되는 정밀 금속 성형 공정이다. 아이어닝 공정은 대개 냉간상태에서 행하여지며 그리고 때로는 단공정 대신에 다단식이 적용된다.본 연구의 목적은 강소성 유한요소법으로 단공정과 다단식 아이어닝 공정을 해석하여 아이어닝공정에 대한 적절한 설계변수와 최적 설계조건을 찾는데 있다. 본 연구에서는 공정설계에 있어서 공정변수를 다이의 원추각과 단의 갯수로 주었다. 본 해석에서는 단공정 아이어닝과 다단식 아이어닝 공정의 성형하중, 응력과 변형도 분포 그리고 격자변형을 계산하였다. 그리고 이 값들에 대한 공정변수의 영향을 검토한 결과 성형하중과 격자변형에 있어서 계산 결과와 잘 일치하였다.
The ironing is a precision metal forming process by which dimensional accuracy of the product is precisely controlled. The ironing process is carried out usually in cold condition and often multi-passes are employed instead of a single-pass process. The objective of the present study is to analyze single-pass and multi-pass ironing by the rigid-plastic finite element method and to find proper design parameters and optimal design conditions for the ironing process. In the present study the semi-cone angle of the die and pass number are taken as process parameters in the design of the process. In the present analysis the forming load, stress and strain distributions and grid distortion are determined both for single-pass ironing and multi-pass ironing. Then the effect of process parameters on these values are discussed. Experiments are carried out for tube ironing of aluminum alloy specimens at room temperature. It is then shown that computed results are in good agreement with the experimental observation both in forming load and in grid distortion.
Keywords:Rigid-plastic finite element method/multi-pass Ironing/flow behavior/precision metal forming
- Larraguibel JS, "The Effect of Work-Hardening on Drawing Stresses in Multi-Pass WireDrawing," Proceedings of 4th NAMRC, pp. 147-151 (1976)
- Thomsen EG, "On the Mechanics of Rod and Wire Drawing," Proceedings of 10th NAMRC, pp. 21-26 (1982)
- Thomsen EG, Kobayashi S, "Comparison of Experiment with Theory for Single- and Multi-pass Drawing of Tough Pitch Copper and 2024 Aluminum," Proceedings of 12th NAMRC, pp. 96-99 (1984)
- Busch RK, "Untersuchungen uber das Abstreckziehen von Zylindrischen Hohlkorpern bei Raumtemperatur," Berichte aus dem Institut fur Umformtechnik, University Stuttgartt (TH) (1969)
- Hill R, "The Mathematical Theory of Plasticity," Oxford at the Clarenden Press (1950)
- Dodd B, J. Strain Anal., 14(2), 43 (1989)
- Avitzur B, Handbook of Meta-Forming Processes, A Wiley-Interscience Publication, John Wiley & Sons (1983)
- Odell EI, Trans. ASME J. Eng. Ind., 100, 31 (1978)