|
Abstract:
The
accuracy of mechanical properties of sheet described by material model
parameters has great influence on the accuracy prediction of springback.
The material identification process can be time consuming if
simulation model of experiment is complex. An inverse method, which is
combined with FEM software ANSYS LS-DYNA and modified Levenberg Marguart(LM) optimization algorithm, is adopted to identify the
parameters in Barlat 1991 modal based on tensile test with rectangular
specimens. It is time efficient and converges fast using this method to
identify material parameters. There are two steps in the identification
procedure. Firstly the Hill transversely anisotropic model is used and
data from tensile test with specimen in rolling direction are adopted to
calculate parameters in the hardening model. Secondly Barlat 1991 model
is used and data from tensile test with specimens in 0°，45°，90° against
rolling direction are adopted to calculate the parameters in the yield
function. Results show that the parameters identified can predict the
mechanical properties of the material relative accurately.
Key words:
Anisotropic
Inverse identification Hardening model Yield function
CLC No: TH132.43
福特基金(50122154)和2004年新世纪人才计划资助项目.
Received 20050503, received in revised
form 20051006
|