The PROMETRA Program: Plane Strain Tests on Fresh and Highly Irradiated Zircaloy-4, ZIRLO~® and M5`(™) Fuel Claddings

摘要

In the framework of the PROMETRA program, clad hardening constitutive laws (stress-strain curves) have been already implemented in the SCAN AIR code. These laws were derived from uniaxial hoop tensile tests performed on narrow machined ring samples. However, they do not reproduce the conditions of strain multiaxiality acting on cladding during a RIA As a consequence, a new specimen called Plane Strain Tensile (PST) similar to the annular sample developed by Pennsylvania State University has been developed at CEA on a wider notched ring It aims to accurately predict the cladding failure in more prototypical conditions, close to plane strain hoop tension in the middle of the gage section. This paper details the PST tests implementation and results in the framework of the PROMETRA program on fresh and irradiated claddings. The development of this test has led also to the development of a technique to measure local deformations in the gage section of the PST specimen using 2-D Digital Image Correlation (DIC) Tests performed on fresh Zircaloy-4 and on irradiated Zircaloy-4, M5~(™ ) and ZIRLO~® specimens are analyzed relying of post-test examinations and finite element simulations. A synthesis of the interpretation of the tests is proposed