| Abstract Scope |
Prolonged irradiation of structural metals results in the formation of excess microstructural defects, increased maintenance costs, and diminished confidence in components. The evolution of helium content and morphology are key to this form of aging, yet the ways in which helium impacts materials strength are only partially understood. A systematic study was thus performed on α-Ti and Cu implanted at various temperature-dose-dose rate conditions. Implanted samples were characterized using electron microscopy and micro-mechanical testing to determine stable conditions for the formation of atomic clusters, spherical bubbles, and faceted bubbles of helium in the model HCP and FCC metals. Helium morphologies (i.e., feature type, size, and density) are considered in terms of nucleation and growth control, the viability of implanting them uniformly throughout micro-scale test specimens (i.e., > 100 μm), and their consequences for materials strength. |