4th INTERNATIONAL CONFERENCE ON RHEOLOGY
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SESSION 4: Avalanche Dynamics in Rheology and Phase Transitions (ADRPT)
A large number of papers appeared over the last 10 years in this field with real progress being made for the last 5 years. Several reviews have been written and research activities are large in the US, Europe (mainly UK and Spain and France) and in China and Japan. Other countries have smaller groups but have contributed greatly, in particular Finland. The critical mass of this research is clearly there.
Most work on avalanche statistics has been done in thermodynamic (quasi-) equilibrium. Renormalization theory was dominant but mean field theories become more popular now. Experimentally, the control parameter is temperature and strain rates. The approach is then to say "what probability exists at what temperature to find avalanches".
On a finer scale, avalanches are a rheological phenomenon, however. An external force is applied and the system changes into another configuration. This change is not completely smooth but involves jerky movements. These are similar to the situation in slip-stick models (where some of the first avalanches were found). In between it is clear that the phenomenon is much wider and that both computer simulations (very large systems > 1 million atoms), analytical theory and experiments are needed. Experiments were traditionally in shape memory metals but have recently proceeded to oxide materials and multi-ferroic materials. A large area is not the compressional collapse of porous materials under uniaxial stress. The avalanche exponents were followed over 6 orders of magnitude. Inferroelastic phase transitions, the avalanche mechanism is related to the movement of twin boundaries where most papers were published within the last 3 years.
Session ADRPT provides a platform among leading international scientists and researchers both of rheology and materials sciences including physicists, chemists, mineralogists, mechanics, mathematicians, engineers and PhD students for discussion and simulation of the recent achievements in rheology and in research and development of avalanche dynamics in rheology and phase transitions.
Prof. Dr. Karin DAHMEN
University of Illinois at Urbana
Prof. Dr. Xavier ILLA
Universitat de Barcelona
Prof. Dr. Xiangdong DING
Xian Jiaotong University
Any abstracts and scientific presentations related to avalanche dynamics in rheology and phase transitions are welcome.