A combined FEA and design of experiments approach for the design and analysis of warm forming of aluminum sheet alloys

This paper presents a methodology to effectively determine the optimal process parameters for warm forming of lightweight materials using finite element analysis (FEA) and design of experiments (DOE). The accuracy and effectiveness of FEA are verified through comparisons of the achievable part depth values and forming limits predicted from FEA with those from experimental measurements in a wide range of warm-forming conditions. A DOE approach along with FEA is proposed to offer rapid and relatively accurate design of warm-forming process, especially for large parts that require 3D FEA. In addition, strain distributions on the formed part are obtained under a variety of process conditions to gain a better understanding of the warm-forming mechanisms and further investigate the effects of forming temperature, friction condition, forming speed, and blank holding pressure on forming performance. Results of this study reveal that much-improved formability can be efficiently gained with a well-controlled warm-forming parameters.