16th International Conference on Composite Structures ICCS 16 A. J. M. Ferreira (Editor) FEUP, Porto, 2011 SANDWICH STRUCTURES UNDER IMPACT: A STATE-OF-THE ART Albertino C. Arteiro * , Paulo Nóvoa † , Ivo Costa † , Paulo Neves ‡ and António T. Marques * * Departamento de Engenharia Mecânica (DEMec) Faculdade de Engenharia da Universidade do Porto (FEUP) Universidade do Porto Rua Dr. Roberto Frias, 4200-465 Porto, Portugal e-mail: {em07127, marques}@fe.up.pt, web page: http://www.fe.up.pt † Instituto de Engenharia Mecânica e Gestão Industrial (INEGI) Universidade do Porto Rua Dr. Roberto Frias, 4200-465 Porto, Portugal e-mail: prnovoa@inegi.up.pt, web page: http://www.inegi.up.pt ‡ Instituto de Engenharia Mecânica (IDMEC) Universidade do Porto Rua Dr. Roberto Frias, 4200-465 Porto, Portugal e-mail: pneves@feup.idmec.pt, web page: http://www.fe.up.pt/idmec Key words: Sandwich structures, Low velocity impact, Interleaved core material, Cork, Manufacturing processes Summary. This work introduces the state-of-the-art of sandwich structures for impact applications, namely under low velocity impact events. Cork will have particular emphasis as an interleaved core material. Finally, some of the manufacturing processes emphasized, in the last years, by core materials manufacturers will be presented too. 1 INTRODUCTION The number of applications of sandwich structures is increasing. For this reason, study of sandwich structures’ mechanical and structural mechanisms is getting more and more important. Low velocity impact is one of these mechanisms, and its study is considered to be very important. Cork will have particular emphasis as a core material because of its particular properties for impact situations. A sandwich composite is a construction which features a combination of two very thin high strength composite laminates with a lightweight core material between them. Core materials must be extremely lightweight and must transfer the shear effort between the skins that compose the sandwich structure. Therefore, the primary properties in choosing a core are the shear strength and modulus. Moreover, in order to avoid buckling, that may occur in the