Numerical and experimental fatigue strength evaluation of thin-walled aluminum components for aerospace application manufactured by roll forming

Abstract

The design of structural components for use in commercial aircraft places high demands on the safety under static and cyclic loading conditions during the total operating time. With immerging innovative developments in the production of thin-walled sheet metal components, savings in energy consumption and material are achievable by switching from metal-cutting production to forming operations. As the forming process has an impact the local material properties due to resulting residual stress state, cold working and surface finish, the fatigue life estimation requires the consideration of the forming history. The structural component under consideration from aluminum alloy EN AW-7475 T761 is manufactured by automated, robot-assisted roll forming. Potentially existing residual stresses are determined via process simulation of the angled profile utilizing commercial finite element solver LS-Dyna®. The fatigue life assessment is carried out using the Local Strain Approach for different loading conditions.