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Advanced materials including metal matrix, ceramic metal matrix and other composites/metals are critical to numerous applications associated with the development of next-generation aircraft architectures whose goal is to produce aerospace platforms that are more cost efficient, safe and reliable. The wide variety of advanced materials used in aerospace construction creates significant challenges for existing material characterization technologies. Photon Induced Positron Annihilation and related technologies are currently being used to assess fatigue, thermal degradation, creep, and embrittlement in aircraft components composed of advanced composite and metal alloy materials from initial manufacture through failure, thereby providing a new reliability assessment tool for pre- and post-mission component evaluations and likelihood-of-failure assessments.

Ceramic thermal barrier coatings (TBC) and surface treatments are being developed for advanced turbine engine applications to provide critical insulation that results in lower component temperatures and extended fatigue life. This translates into improved reliability and efficiency with reduced life cycle costs. However, the durability of these coating systems remains a crucial issue at the higher operating temperatures and extended exposure times associated with current and next generation turbine engine designs. Standard inspection techniques are unable to detect pending TBC failure or other surface treatment failures until they have already occurred and with possibly, catastrophic effects. Distributed Source Positron Annihilation technology is a portable, near-surface inspection tool that has demonstrated the capability to quantify microstructural changes in surface treatments and TBCs.