Characterizing Interfacial Properties Using Ultrahigh Temperature In Situ TEM Based Mechanical Loading and Coupled Ion Irradiation

Interfaces play a dominant role in determining materials properties despite their relatively small volume fractions. Their small volume fraction and unique structural motifs present challenges for many characterization methods. As a result, mechanisms associated with interfacial transport remain poorly understood. Interface mediated creep provides an effective route to characterize interfacial thermodynamics and kinetics, especially if the testing geometry can be idealized. Small scale mechanical loading enables both convenient testing of individual interfaces and in situ irradiation under conditions that produce relatively uniform displacement damage rates. Localized heating, furthermore, enables access to extreme temperatures. This talk describes recent efforts to utilize such experiments to probe interfacial transport mechanisms in metals and ceramics and understand how irradiation induced defects interact with interfacial sinks. Differences between how interfacial point defect sinks respond to irradiation versus thermal processes will be discussed.