Proceedings of the Korean Society for Technology of Plasticity Conference (한국소성가공학회:학술대회논문집)
- 2005.10a
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- Pages.362-365
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- 2005
Development of the technique for prediction of the hub-hole crack with the punching effect
펀칭 효과를 고려한 허브홀의 파단 예측기법 개발
Abstract
The hub hole is usually formed with a flanging process followed by a blanking process of a ]tole. Since the hole is made by blanking, the blanked surface is so rough that the formability in the region is rather poor. The emerging task is to identify the formability of the blanked region in the forming simulation and to relate the criterion to the real forming process by experiments. In this paper, hole expansion tests are carried out with respect to various hole conditions to verify the hole condition effect on the hole expansion ratio. The hole of specimens is made by machining or punching. In the case of punching, two different punching clearances are used for making the hole. From the results of test, fracture mechanism of the hole expansion is explained.
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