TY - CHAP

T1 - Reduction of springback by use of deep drawing tools with locally and temporally varying stiffness

AU - Mennecart, Thomas

AU - ul Hassan, Hamad

AU - Fruth, J.

AU - Wagner, T.

AU - Güner, Alper

AU - Ben Khalifa, Noomane

AU - Tekkaya, A. Erman

PY - 2013

Y1 - 2013

N2 - With the increased use of high strength steels in automotive industry, the springback also became a big problem which has to be reduced already during the design process. For the case of low production volumes, as in the design process, deep drawing tools can be made of polymers. In these tools different regions of stiffness can be created by use of springs or actuators. Actuators allow the temporal variation of stiffness while springs allow just a local adjustment. With the use of tools with such stiffness varying elements it is possible to reduce the springback and to improve the forming quality of the final part. In the experiments, deep drawing tools are made of polymers and elements for the stiffness adjustment are positioned in the die and in the blankholder. Such stiffness varying elements are positioned at the radii where springback can be reduced by increasing tension in the part by adjusting the stiffness to a suitable level. Actuators allow smooth changes of stiffness during the forming process. Finite element method (FEM) based simulations of the processes are also performed. The comparison of results is carried out and a profile of optimal variation of tool stiffness is generated to minimize the springback. In the experiments a small reduction of geometry deviation of the parts could be reached by varying the stiffness with springs and actuators placed into the die.

AB - With the increased use of high strength steels in automotive industry, the springback also became a big problem which has to be reduced already during the design process. For the case of low production volumes, as in the design process, deep drawing tools can be made of polymers. In these tools different regions of stiffness can be created by use of springs or actuators. Actuators allow the temporal variation of stiffness while springs allow just a local adjustment. With the use of tools with such stiffness varying elements it is possible to reduce the springback and to improve the forming quality of the final part. In the experiments, deep drawing tools are made of polymers and elements for the stiffness adjustment are positioned in the die and in the blankholder. Such stiffness varying elements are positioned at the radii where springback can be reduced by increasing tension in the part by adjusting the stiffness to a suitable level. Actuators allow smooth changes of stiffness during the forming process. Finite element method (FEM) based simulations of the processes are also performed. The comparison of results is carried out and a profile of optimal variation of tool stiffness is generated to minimize the springback. In the experiments a small reduction of geometry deviation of the parts could be reached by varying the stiffness with springs and actuators placed into the die.

KW - Engineering

UR - http://www.gbv.de/dms/tib-ub-hannover/772841578.pdf

M3 - Article in conference proceedings

SN - 9783851252941

SP - 309

EP - 320

BT - TTP2013 conference proceedings

A2 - Kolleck, Ralf

PB - Verlag Technische Universität Graz

T2 - Conference Tools and Technologies for Processing Ultra High Strength Materials - TTP 2013

Y2 - 19 September 2013 through 20 September 2013

ER -