Numerical prediction of thermal panel distortion in automotive paint shop

Abstract

Challenging automotive design in the face of modern lightweight strategies for weight reduction as well as legislative regulations, impose higher requirements for future car body development. This trend has led to the use of thinner sheet metal blanks and implies the need for narrow process windows especially within the coating process where thermal loads might cause local shape deviations. Moreover, developments in multimaterial design induce material configurations with complex deformation behaviour due to different expansion characteristics. For this reason, there is a need to improve the numerical prediction of surface quality in the early car development process. This paper deals with the effect of thermomechanical material properties relating to the final part characteristics, whereby the influence of time and heat dependent material properties affecting the yield point and flow characteristics is shown. In further investigations, the influence of initial yield strength, pre-stretching and subsequent thermal loads to the final yield strength is dealt with.

Keywords:

• Thermal distortion
• Distortion simulation
• Material properties
• 6xxx aluminium alloy