.png){kind=icon}
Return
Modelling time-dependent relaxation behaviour using physically based constitutive framework
.png){kind=icon}
PRE
AI
DOI：10.1016/j.ijmecsci.2024.109209.png)
.png){kind=icon}
Original request for help.png){kind=icon}
Share.png){kind=icon}
Save
Abstract
En 中文
The application of interrupted die motion during the deformation process in a servo press cycle is known to enhance the forming limit of metallic materials. This observation is generally attributed to the transient effects associated with stress relaxation phenomenon. However, attempts to model stress relaxation behaviour using physically based constitutive formulations in the finite element method are scarce. In this work, a modified version of the Kocks-Mecking-Estrin (KME) dislocation density model is used to evaluate the substructural changes during relaxation. An 'uncoupled' elasto-viscoplastic approach is employed to accommodate the plastic strain rate effect. This modelling approach is implemented in the commercial finite element software via a user material subroutine. The model is validated through simulations of interrupted uniaxial tensile tests for aluminium alloy AA7075 under two different aging conditions. The implemented model is shown to closely capture the experimental results and account for changes in dislocation density and the athermal component of flow stress during relaxation. Subsequently, the model is applied to simulate monotonic and interrupted hole expansion tests (HET), and the results are discussed qualitatively.
Keywords:
Stress relaxation
Dislocation density
Finite element method
User material subroutine
Uniaxial tensile test
Hole expansion test
Journal
IF:
9.4
Papers:
1.0W
Citations:
4.5W
Organization
Cited Papers
.png){kind=icon}
ShareSaveShareSaveShareSaveShareSaveShareSave
ShareSaveShareSave
View more