Influence Of The Allotropic Alpha/Beta Phase Transformations On The Mechanical Behaviour Of Zirconium Base Alloys During And After High Temperature Transients In An Oxidizing Environment ("Loca" Conditions)

This paper deals with zirconium base nuclear fuel cladding tube behaviour upon high temperature "Loss Of Coolant Accidental" (LOCA) transients. Upon such hypothetical scenarii, the cladding materials experience strong metallurgical evolutions (i.e., heating/cooling alpha/beta allotropic phase transformations, oxygen (and hydrogen) ingress/diffusion due to the high temperature oxidation, etc.). The present paper gives an overview of the consequences of such deep metallurgical evolutions on the mechanical properties during and after typical high temperature LOCA transients.