Anisothermal behaviour of unirradiated CWSR zircaloy-4 fuel clads under RIA conditions

This paper presents new experimental thermo-mechanical tests recently developed in order to understand the behaviour of fuel clads under anisothermal conditions. The experimental setups permitted material testing in complex conditions representative of real RIA loading (high strain and heating rates) coupling simultaneous mechanical and thermal loading. Mechanical properties are studied and compared to isothermal ones. Results showed a clear history effect at low strain rates, this effect seems to disappear at high strain rates due to rapid mechanical loading which limits heating before failure. 2D and 3D FEM are illustrated with applied thermo-mechanical loadings. These numerical simulations allowed us to evaluate the history effect during anisothermal tensile tests using a constitutive law identified on isothermal uniaxial tests