Radiation and Thermomechanical Degradation Effects in Reactor Structural Alloys

Abstract

Abstract Structural materials in nuclear energy systems are exposed to a variety of operating conditions that can produce significant degradation in material properties. This chapter provides an overview of the degradation processes in structural alloys associated with elevated temperatures, applied mechanical stress, and neutron irradiation. In particular, phase instabilities due to prolonged thermal aging (with or without applied mechanical stress), thermal creep, and creep-fatigue phenomena will be summarized as key thermomechanical processes. Radiation-induced degradation processes include low-temperature radiation hardening and embrittlement, radiation-modified solute segregation and precipitation, radiation- and stress-modified corrosion and cracking, dimensional instabilities associated with void swelling, irradiation creep and radiation growth, and high-temperature helium embrittlement. General time-, temperature-, stress-, and radiation dose-dependent behaviors are outlined for structural alloys. Specific data for particular structural alloys are described in Chapters 7–13 7 8 9 10 11 12 13 in this book.