Affiliation:
1. School of Mechanical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, China
2. State Key Laboratory of Deep-Sea Manned Vehicles, China Ship Scientific Research Center, Wuxi 214082, China
Abstract
The internal hydroforming of large stainless-steel eggshells from a stepped preform is investigated in this paper. The nominal major and minor axes of the eggshell were 1537 and 1070 mm, respectively. The stepped preform was fabricated from thin-walled (1.9 mm thick) stainless-steel sheets and comprised twelve conical segments inscribed inside the target eggshell. The preform was then hydroformed, and its wall thickness and shape were measured. The yield load distribution and material hardening of the hydroforming process were investigated analytically. Nonlinear finite-element analyses were employed to further investigate hydroforming behaviors and the effect of weld lines on hydroforming. The experimental, numerical, and analytical results were consistent. The results confirm that, during the hydroforming process, considerable springback occurs for large eggshells, which greatly affects forming precision. However, this effect can be reduced by accounting for the strengthening effect of weld lines.
Funder
National Natural Science Foundation of China
Subject
General Materials Science,Metals and Alloys
Reference67 articles.
1. Wong, H.T. (2005). Behaviour and Modeling of Steel-concrete Composite Shell Roofs. [Ph.D. Thesis, Hong Kong Polytechnic University]. UMI Number 3205524.
2. Chen, F., and Sha, S. (2005, January 11–13). An Introduction to Bridge Design Based on Bionics. Proceedings of the 24th Annual Southern African Transport Conference (SATC 2005), Pretoria, South Africa.
3. Egg-Inspired Engineering in the Design of Thin-Walled Shelled Vessels: A Theoretical Approach for Shell Strength;Narushin;Front. Bioeng. Biotechnol.,2022
4. Investigation on Egg-Shaped Pressure Hulls;Zhang;Mar. Struct.,2017
5. Design Optimization of Composite Egg-Shaped Submersible Pressure Hull for Minimum Buoyancy Factor;Imran;Def. Technol.,2021