Refractory materials and tungsten in particular have been considered for fusion and advanced fission power systems for decades. However, much of the fundamental irradiation effects leading to the known embrittlement issues are not well understood.  What is known is that the irradiation behavior is a function of the crystal response to irradiation and the stability of the grain boundary which is a strong function of the processing route.  To date, much of the irradiation effects studies have been carried out on powder metallurgy materials for which grain boundaries dominate behavior. For these reasons the current database on irradiation effects is both lacking in the fundamental understanding of base material and the materials of interest for next generation devices.  This paper will present a brief summary of the current knowledge-base and results of a new collaboration begun to address these limitations. A recent program to understand the behavior of irradiated tungsten includes polycrystalline tungsten, single crystal W of [100] and [110] orientations in various rolling and anneal conditions, and 0.5 mm thick W/Cu laminates. Specimen types were 0.1�4�16 mm bars and SS-J2 tensile specimens for which tensile testing, ball punch, and microhardness was performed. Fission reactor irradiations were carried out in the 0.02 to 20�1025 n/m2 (E>0.1 MeV) at 90, 300, 500, and 650�C.  In addition to contrasting the mechanical properties and microstructural evolution of the single crystal material with the polycrystalline and engineered materials, the present results will be compared with the literature.  Moreover, implication of the irradiation response as a function of dose and temperature with the viability of tungsten as a nuclear structural material will be discussed.

Tunsten as a nuclear structural material

247th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.