A novel method to alleviate flash-line defects in coining process

作者：Xu Jiang ping; Khan Kamran A; El Sayed Tamer^*

来源：Precision Engineering-Journal of the International Societies for Precision Engineering and Nanotechnology, 2013, 37(2): 389-398.

DOI：10.1016/j.precisioneng.2012.11.001

• Coining
• Flash line
• Constitutive model
• Radial friction work
• Finite element analysis

We employ a finite element framework based on a dynamic explicit algorithm to predict the flash-line defects in the coining process. The distribution of the flash-line is obtained by building a radial friction work model at the element level. The elasto-plastic behavior of porous materials undergoing large deformations is considered where the constitutive level updates are the result of a local variational minimization problem. We study the material flow at different strokes of the die across the entire coining process and observe that the change in the flow direction of the material in the rim region may contribute to the flash lines. Our proposed framework shows that a part of the rim region in which the flash-line defects appear is consistent with the reported experimental results: We also propose a novel method of redesigning the rim geometry of the workpiece to alleviate the flash-line defects which also shows good agreement with experiments.

• 出版日期2013-4