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When drawing non-axissymmetric sheet metal parts it is necessary to control the flow of material between the lower and upper binder in such a manner that prevents the occurrence of both tears and wrinkles in the drawn part. One possibility for the control of the material flow is through the deliberate adjustment of the normal forces. If one can measure the flow-in of the material into the die cavity as a function of punch stroke with a special sensor, and if this information can be used to produce an empirical flow-in curve over the stroke for good parts, then it is possible to construct a closed- loop BHF control system. Building such control system is feasible by implementation of special dies with hydraulically supported segmented binders. This system allows an automatic response to a change in the friction conditions.

The costs for development and production of draw dies for car outer panels are extremely high and should be reduced. Furthermore it is necessary to reduce the time for developing, designing and producing the dies for the production of parts. This paper discusses new press techniques, die designs and an adjustment program for press operators. The trend goes to single action presses with CNC-controlled multipoint cushion systems in the press table and to special designed dies. These systems lead to a more robust and reproducible forming process with improved product quality. This paper deals with: Cushion Systems, New Binder Designs for Draw Dies for Sheet Metal Automotive Parts, New Computer Program to Adjust the Blankholder Forces of Modern Hydraulic Cushion Systems of Single Action Presses and Pressure Measurement for Detecting the Pressure between the Blank and the Binders of Draw Dies for Sheet Metal Automotive Parts.

In cooperation with industrial companies at the Institute for Metal Forming Technology (IFU) of the University of Stuttgart, Germany, a new press concept specially for hydroforming tubes and extrusions was developed. The press has a capacity of 3500 tons closing force and a press table size of 2500 mm × 900 mm. A great reduction in costs can be achieved by integrating spacers between the frame of the press and the ram. This paper introduces this new press.

Thixoforming is another word for Semi-Solid-Metalforming (SSM) which means that metal will be formed between solid and liquid temperature. In this state the material behavior is thixotropic. Aluminum alloys can be formed in this thixotropic state when 30 to 40% of the material is liquid. In this case it is possible to form the aluminum in a process that is located between the die-casting and the forging technology. The thixoforming process allows it to produce Near Net Shape aluminum-parts with high quality for the automotive industry. This paper is intended to give the reader some examples about and some insights into the possible applications of the thixoforming process.