Impact of a beryllium deposition on the reliability of Zircaloy-4/Zircaloy-4 welds for fuel rods in research reactors (HMWRR)

Abstract

This project assesses the performance of beryllium as a brazing metal for joining Zircaloy-4 structural components (pads and spacers) in nuclear fuel assemblies. This study aims to characterize the properties of the brazed joint and identify the key performance and durability factors under the specific conditions of research reactors. Experimental characterization includes optical microscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and microhardness testing. The results show that surface preparation critically influences joint quality, precise control of beryllium deposition is essential, the interface is homogeneous, and the joints exhibit mechanical stability. These findings confirm the suitability of beryllium brazing for Zircaloy-4 under controlled conditions.