Increasing the Deep Drawability of Al-1050 Aluminum Sheet using Multi-Point Blank Holder

Aluminum alloys have been widely used in the fields of automobile and aerospace industries. Due to their bad cold-formability in deep drawing, a lot of forming methods have been implemented to increase the drawing height and the limiting drawing rate (LDR). The conventional deep drawing process is limited to a certain limit drawing ratio beyond which failure will ensue. The purpose of this experimental study is to examine the possibilities of increasing this limitation using the multi-point blank holder. The results from the experiments showed that the multi-point blank holder is effective way to promote deep drawability of Al-1050 sheet

Forming sheet metals by means of multi-point deep drawing method

Multi-point deep drawing (MPDD) is an advanced manufacturing technology for 3D sheet metal parts and it can form a variety of part shapes without the need for solid dies. In this study, a test set has been prepared for multi-point deep drawing process utilizing the multi-point forming technology. Drawability attributes of gradually rectangular shaped container have been observed using a sheet, which has the quality of Erdemir 7114 and is suitable for deep drawing process, and also using multi-pointed punch with a given tool geometry and a draw velocity. The blank shape to be drawn without wrinkling and tearing has been determined. Wrinkles and dimples are the major forming defects in the MPDD process. In conventional deep drawing, the method to form sheet metal with a blank holder is an effective way to suppress wrinkling; and the same is true in MPDD. The process of multi-point forming technology decreases production cost of die, provides flexible usage, and it is convenient to achieve the most even deformation distribution. © 2006 Elsevier Ltd. All rights reserved

Study on forming tool module with variable stiffness blank-holder for applications in high strength steel and laser welding parts

This study presents experimental and numerical results of a development prototype tool that includes blank-holder plates of variable stiffness. The application is analyzed for high-strength steel parts and tailor welded blanks manufactured from dissimilar steel grades using laser welding. A numerical model was constructed within the Ansys software platform incorporating appropriate material constitutive models parameters for high-strength Dual-Phase steels. The obtained results show a positive control of springback geometries. Experimental tests were performed on the relevant geometries. The presented numerical and experimental results constitute a validation of a variable-stiffness blank-holder approach for this particular case study.The funding support from Project I&DT AdvancedTOOLING CENTRO-01-0247- FEDER-011399 is acknowledged