The effect of friction and lubrication modelling in stamping simulations of the Ford Transit hood inner panel: a numerical and experimental study

Abstract
Reducing weight of Body in white (BIW) is a well-known solution to tackle environmental issues in automotive industry. Replacing steel by lighter aluminium sheet material is an accepted alternative. However, this trend brings challenges like the forming of Aluminum into complex car body parts. These challenges signify the necessity of more advanced tools to obtain defect-free parts. Nowadays, it is a common practice to implement forming simulations at the early stage of part design in order to identify critical features and to optimize the production process. Although, it is known that friction and lubrication conditions are one of the most influential sources affecting product quality in aluminium sheet metal forming, it is currently not considered in detail in stamping simulations. The current application case focuses on the role of friction and lubrication modelling in stamping simulations of an aluminium hood inner part of the new Ford Transit. A comparison was made between different friction models to identify and resolve split issues in the forming simulations. Simulation results were used to guide try-out towards efficient and successful elimination of these issues on the physical panels. Finally, different possible scenarios corresponding to production conditions were investigated to define a robust process window.