Quarterly Report 9/30/03

Couch, R G

Lawrence Livermore National Laboratory

关键词: Modifications;    Lawrence Livermore National Laboratory;    Fractures;    Strain Rate;    Functionals;   

DOI  :  10.2172/15013827
RP-ID  :  UCRL-TR-200126
RP-ID  :  W-7405-ENG-48
RP-ID  :  15013827

美国|英语

来源: UNT Digital Library

【 摘 要 】

In this quarter, LLNL personnel traveled to the Alcoa Technical Center to discuss the current status of simulations and experiments. The previously-noted deficiencies of the fracture model were discussed in detail as were ways to improve its functional form to ensure reasonable behavior over a wider range of pressures and strain rates. Additional experiments to calibrate the model at low strain rates and high triaxiality were reviewed. We expect that ATC will provide the refined fracture model to LLNL shortly. Once available, appropriate modifications will be made in the FEM subroutines, and the validation process for ingot fracture will continue. A simulation is being performed to validate the FEM model for a production facility mill configuration. The current focus is on the evolution of the deformed slab shape with increasing number of reduction passes. A detailed comparison of the slab side profile with experimental results is currently being carried out to identify key parameters controlling the simulated shape. Preliminary results show that the friction model plays a dominant role in the intermediate and final profile shapes. Using details of the deformed shape as a validation metric, additional simulations will be performed to optimize parameter values.