Impact of Second Phase Particles on BWR Zr-2 Corrosion and Hydriding Performance

摘要

BWR fuel cladding corrosion and hydriding performance may limit the fuel residence time. Historically, out-of-pile high-temperature steam tests have been used to predict the BWR corrosion performance of Zircaloy materials. However, results indicate that no correlation exists in many cases between in-pile and out-of-pile Zircaloy corrosion performance. Concerning BWR hydriding performance there appears to be no reliable out-of-pile test that predicts the BWR Zircaloy hydriding performance. The Zircaloy corrosion and hydriding performance is a function of: 1. The environment such as the temperature, fast neutron flux, water chemistry. 2. The Zircaloy microstructure, such as texture, dislocation density, matrix chemical com-position, and second phase particle SPP characteristics. One way to solve the problem with the lack of reliable out-of-pile tests is to correlate the BWR Zircaloy corrosion and hydriding performance to the initial microstructure. Such a correlation will of course not predict the impact of temperature, fast flux, and water chemistry on Zircaloy corrosion and hydriding performance.