Unconstrained bending and springback behaviors of aluminum-polymer sandwich sheets

作者:Liu, Jianguang*; Xue, Wei
来源:International Journal of Advanced Manufacturing Technology, 2017, 91(5-8): 1517-1529.
DOI:10.1007/s00170-016-9819-2

摘要

The bending and springback behaviors of sandwich sheets are more complicated than those of monolithic layer metallic sheet due to the extremely large difference in mechanical properties and in the gauges of polymer core and the skin sheet. In the present study, the bending and springback behaviors of aluminum-polymer sandwich sheets were investigated by using analytical method and conducting experiments and numerical simulations. A simplified analytical model was proposed to calculate the bending moments for sandwich sheet in unconstrained bending process through analyzing the strain and stress distributions of skin sheet and core materials. Then, the analytical model was applied to predict the springback of sandwich sheets after bending. Numerical simulations and experiments of unconstrained bending process for aluminum-polymer sandwich sheets were conducted to investigate the influences of mechanical properties of each layer and thickness ratio of two layers on the folding defects, neutral layer location, and springback. The results show that the neutral layer shifts dramatically toward the compression region of the specimen during bending. The folding angle mainly relates to the strength difference between the skin sheet and the core polymer. The springback angle of sandwich sheet is mainly determined by the mechanical properties of skin sheet.

  • 出版日期2017-7
  • 单位中国商用飞机有限责任公司北京民用飞机技术研究中心; 哈尔滨工业大学