The 4th International Conference on Matter and Radiation at Extremes (ICMRE 2019)

400 / 2019-02-28 17:52:48

Constitutive Model of Long-term neutron irradiated Al-Mg-Si alloy under High Temperature and High Strain Rate

solid mechanics,irradiation damage,dislocation kinetic constitutive model,SHPB,neutron-irradiated Al-Mg-Si alloy

Plenary track > High Pressure Physics and Materials Science

The material used in this study is a decommissioned Al-Mg-Si alloy, obtained from the upper containers close to the reactor core. The aluminum alloy has been exposed to high flux neutron and energetic particles, and their properties are changed considerably over a period of nearly 30 years of service.The quasi-static and dynamic compressive mechanical behavior of decommissioned Al-Mg-Si alloy from reactor was investigated by using MTS and SHPB at different experimental temperatures and loading strain rates. The influence rules of experimental temperature and loading strain rate on yield strength and work hardening behavior of decommissioned Al-Mg-Si alloy exhibits excellent plasticity under compressive stress. Yield strength and flow stress increase obviously with the increase of loading strain rate in a certain range of strain rate，and decrease radually with the increase of experimental temperature in a certain range of temperature ，showing significant positive strain rate sensitivity and thermal softening effect. When the loading strain rate is higher than 3000 s-1 at room temperature, the strain rate is insensitive. When the experimental temperature rises to 300℃，it tends to be perfectly plasticity. Finally，the dislocation kinetic constitutive model (Zerilli-Armstrong constitutive model) considering radiation damage was developed to predict the deformation behavior of decommissioned Al-Mg-Si alloy over a wide range of temperatures and strain rates. The calculation results of the model are in good agreement with those achieved from the experiment.