|Search for content and authors|
Comparison of the strain distribution obtained from multi scale and conventional approaches
|Lukasz Madej 1, Peter D. Hodgson 2, Maciej Pietrzyk 1|
1. AGH University of Science and Technology (AGH), al. Mickiewicza 30, Kraków 30-059, Poland
Multi scale modelling of material response under various loading conditions is a commonly used method of solving practical problems. One of the approaches is multi scale technique based on combination of cellular automata (CA) and finite element (FE) method - CAFE method. Creation of rheological model in the micro scale, capable of predicting discrete and discontinuous processes, is the main advantage of this approach.
This work is part of an investigation connected with application of the developed CAFE model to prediction of strain localization in various industrial processes. Model capabilities to predict the development of micro shear and shear bands in different scales are crucial during metal forming operations, when localized deformation limits ductility and may lead to fracture. On the other hand, materials formability may be extended when the development of shear bands is precisely controlled during entire deformation.
Comparison of the strain fields predicted by FE and CAFE models is the general objective of the project. Extrusion process, which involves strong strain localization, was selected as an example. This selection was motivated by experimental observations showing highly localized shear band zone with flow discontinuity that occurs in the deformation area. Shear zone influences the final product microstructure and may lead to coarse grain layer close to the surface. Modelling of the shape of this zone and prediction of strains will create a possibility of computer aided design of extrusion process and optimization of technological parameters. Conventional FE models give the results, which do not agree well with experimental observations. The developed CAFE model predicts larger values of strains and narrower strain localization zone, which is closer to the experimental observations. Advantages and disadvantages of the CAFE model are discussed as well.
Presentation: Oral at E-MRS Fall Meeting 2006, Symposium H, by Lukasz Madej
See On-line Journal of E-MRS Fall Meeting 2006
Submitted: 2006-05-05 04:14 Revised: 2009-06-07 00:44