Thickness distribution of multi-stage incremental forming with different forming stages and angle intervals

• Published in: Journal of Central South University Vol. 22; no. 3; pp. 842 - 848
• Main Authors: Li, Jun-chao, Yang, Fen-fen, Zhou, Zhi-qiang
• Format: Journal Article
• Language: English
• Published: Heidelberg Central South University 01.03.2015
• Subjects: Engineering; Metallic Materials; multi-stage forming; angle interval; incremental forming; thickness distribution
• ISSN: 2095-2899; 2227-5223
• DOI: 10.1007/s11771-015-2591-x

Although multi-stage incremental sheet forming has always been adopted instead of single-stage forming to form parts with a steep wall angle or to achieve a high forming performance, it is largely dependent on empirical designs. In order to research multi-stage forming further, the effect of forming stages ( n ) and angle interval between the two adjacent stages (Δ α ) on thickness distribution was investigated. Firstly, a finite element method (FEM) model of multi-stage incremental forming was established and experimentally verified. Then, based on the proposed simulation model, different strategies were adopted to form a frustum of cone with wall angle of 30° to research the thickness distribution of multi-pass forming. It is proved that the minimum thickness increases largely and the variance of sheet thickness decreases significantly as the value of n grows. Further, with the increase of Δ α , the minimum thickness increases initially and then decreases, and the optimal thickness distribution is achieved with Δ α of 10°. Additionally, a formula is deduced to estimate the sheet thickness after multi-stage forming and proved to be effective. And the simulation results fit well with the experimental results.