In this paper, a local surface nanocrystallization technology is used for thin-walled structures with square cross sections, and an energy absorption device of two-staged combined energy absorption structure is proposed. In virtue of the surface nanocrystallization that enables to change the material on local positions, the structural deformation is induced and controlled to maximize the energy absorption capacity. A numerical model of the two-staged combined energy absorption structure is established, and the local surface nanocrystallization layout is optimized. The results show that the specific energy absorption of two-staged combined structure with local surface nanocrystallization can be increased by 34.36% compared with the untreated counterpart of the same material and structural shape. The ratio between the first and second peak crushing forces and the energy absorption allocation ratio between the two stages can be adjusted in the ranges of 0.26–0.55 and 0.31–0.45, respectively, which can be controlled by the local surface nanocrystallization designs. The numerical simulation and experimental results are in good agreement, which shows that the design for energy absorption device with local surface nanocrystallization is feasible and effective.
"Acta Mechanica Solida Sinica" – Springer Journals
Published: Oct 19, 2021
Keywords: Local surface nanocrystallization; Two-staged energy absorption; Square cross-sectional thin-walled structure; Specific energy absorption