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For conventional sheet metal forming at room temperature, numerous tribometers were developed in the 20th century. At the present state of the art, unsolved issues for tribometry remain for temperature-supported forming processes of high strength aluminum (e.g. EN AW-7075), in which the sheet is heated to temperatures between 200 and 480 °C. The tribological design of these processes remains a major challenge, which needs to be addressed by investigations with adapted tribometers. In this study, a recently adapted strip drawing test for aluminum warm and hot forming is presented – including a newly developed strip heating unit, a die lubrication system and a die tempering system for efficient tribological testing. The contribution is completed with both, experimental results and a numerical investigation of temperature gradients in the strip drawing test. Finally, it is discussed whether transient process conditions of non-isothermal forming processes with die lubrication should be considered in tribometers for warm and hot sheet metal forming.

For conventional sheet metal forming at room temperature, numerous tribometers have been developed in the 20th century. At the present state of the art, there are some challenges for tribometry in warm and hot forming processes of high‐strength aluminum (e.g., EN AW‐7075). Especially for nonisothermal processes with heated sheets and cooled dies, the tribological design is a major challenge, which needs to be addressed by investigations with adapted tribometers. Herein, the transferability of friction and wear behavior of three different lubricants and temperatures is investigated. Therefore, tribometer test results are compared with real forming trials in combination with thermomechanical finite element simulations. Both the behavior of different lubricant types and the characteristics of tool lubrication in sheet metal forming are discussed.

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Temperaturunterstützte Prozesse bieten die Möglichkeit, hochfeste Aluminiumlegierungen umzuformen. Im Beitrag wird das Potenzial der Halbwarm- und Warmumformung sowie der W-Temper-Umformung der hochfesten Aluminiumlegierungen EN AW-6082-T6 und EN AW-7075-T6 in einem 90°-Gesenkbiegeversuch aufgezeigt. Im Rahmen der Untersuchungen werden Variationen entscheidender Umformparameter (Biegeradius und Temperatur) durchgeführt und Prozessgrenzen ermittelt.   Temperature-assisted processes offer the possibility of forming high-strength aluminum alloys. In this article, the potential of warm and hot forming as well as W-Temper forming of the high-strength aluminum alloys EN AW-6082-T6 and EN AW-7075-T6 is shown in a 90° V-bending test. Within the investigations, bending tests are carried out varying decisive forming parameters (bending radius and temperature) and process limits are determined.