Defect Improvement of Extrusion Dies Using Combination of Fem Stress Analysis With the Taguchi Method

Abstract

This study aims at analyzing the influence of the maximum principal stress on Tungsten Carbide Steel die core in an extrusion die which caused the crack of die core, and then adjusts the dies assembly method in order to improve the service life of die. In this study, we combine FEM simulation software with the Taguchi Method L9(34) to choose the cobalt content for die core materials, and the quantity of shrink fit while assembling the die core and die case as the reference parameters. When carrying out the simulation process, we compared the changes of the maximum principal stress of the die core caused by the plastic deformation of die materials to achieve the minimum expected value as the goal for the most optimal die combination. Then, the results obtained are to make dies in trial and mass-production practically; as a result, the die life is improved from the original 1000 to 150,000 pcs, which is more than 150 times better than before.

Die Defects and Die Corrections in Metal Extrusion

“…In other cases, further repair is not possible after various die corrections have been done, resulting in the scrapping of the die. Many researchers have attempted to investigate or analyze individual die defects [26,27]. Arif et al [17] conducted a more comprehensive study on die failure modes and mechanisms and presented a statistical analysis of the main die failure types and their sub-divisions.…”