Transactions of Materials Processing (소성∙가공)

The Korean Society for Technology of Plasticity and materials processing (한국소성∙가공학회)
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Void Closing Conditions of Large Ingot by Path Schedules

대형 잉곳의 기공압착 효과 향상을 위한 폐쇄조건 연구

  • Received : 2010.09.29
  • Accepted : 2010.11.11
  • Published : 2010.12.01
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Abstract

In this work, the closing behavior of cylindrical-shaped voids was experimentally investigated according to various parameters such as reduction ratio in height, initial void size and billet rotation during hot open die forging process. The reduction ratio in height, number of path, and billet rotation were chosen as key process parameters which influence the void closing behavior including the change of void shape and size. On the other hand, values of die overlapping and die width ratio were set to be constant. Void closing behavior was estimated by microscopic observation. Based on the observations, it was confirmed that application of billet rotation is more efficient to eliminate the void with less reduction ratio in height. The experimental results obtained from this study could be helpful to establish the optimum path schedule of open die forging process.

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References

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