Development and deployment of a diverse mixture of economic and environmentally sustainable energy sources is important for international energy security. Nuclear (fission) power currently provides 20% of the US electricity, and a variety of fission and fusion energy concepts are under consideration for meeting future energy needs. After a brief review of current and proposed fission and fusion energy systems, the crucial role of high performance materials on possible future pathways for fission and fusion energy systems will be discussed. Key materials science aspects associated with operation in these extreme temperature, mechanical stress and radiation environments will be summarized. Radiation-induced nanoscale complexes that evolve over multiple length and time scales (with the potential for dramatic accompanying property changes) are a recurring feature in many materials systems for nuclear energy. Several strategies to design new high-performance self-healing structural materials will be discussed. Recent exploratory research on potentially improved accident-tolerant fuel systems for fission reactors (motivated by the 2011 accident at the Fukushima Dai-ichi power plants in Japan following the devastating earthquake and tsunami) will also be presented.

Steve Zinkle has been recently named a Governor’s Chair in the Nuclear Engineering Department at the University of Tennessee, Knoxville. Prior to October, 2013, he was the Chief Scientist of the Nuclear Science and Engineering Directorate and a Corporate Fellow at Oak Ridge National Laboratory (ORNL). He previously served as the director of the ORNL Materials Science and Technology Division from 2006 - 2010, and in a variety of research scientist and program management roles since he joined ORNL in 1985 as a Eugene Wigner fellow. Much of his research has utilized materials science to explore fundamental physical phenomena that are important for advanced nuclear energy applications. His research interests include deformation and fracture mechanisms in structural materials and investigation of radiation effects in ceramics, fuel systems, and metallic alloys for fusion and fission energy systems. He received his PhD in Nuclear Engineering and an MS in Materials Science from the University of Wisconsin-Madison in 1985. He has written over 240 peer-reviewed publications, is a recipient of the 2006 U.S. Department of Energy E.O. Lawrence Award, and is a fellow of 6 professional societies including the American Nuclear Society and the Materials Research Society. He is a member of the National Academy of Engineering.