Abstract

Strain path changes are common in complex automotive stampings, where sheet materials undergo a combination of drawing, stretching, and bending to achieve a desired part shape. Aluminum sheet alloys are increasingly used in vehicle structure light-weighting efforts, but limited formability and high levels of springback present challenges to the manufacturing and assembly processes. The current work explores springback levels in AA6016-T4 sheet after various pure bending operations, where sheets were first pre-strained in uniaxial, plane-strain, and biaxial tension. Finite element modeling of the pre-straining and subsequent bending operations will be performed using both isotropic and elasto-plastic self-consistent (EPSC) crystal plasticity approaches. Because the EPSC model incorporates backstresses informed by GND content, as measured via high-resolution EBSD, the predictions are more accurate than those of the isotropic model. The benefits and limitations of the current EPSC model, regarding accuracy of the predictions for the proposed strain path changes, are discussed.

Degree

MS

Rights

https://lib.byu.edu/about/copyright/

Date Submitted

2022-04-19

Document Type

Thesis

Handle

http://hdl.lib.byu.edu/1877/etd12106

Keywords

formability, springback, aluminum, sheet metal, springforward, strain patch change

Language

english

Included in

Engineering Commons

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