PI: Scott X. Mao, Dept of Mechanical Engineering and Materials Science, Univ. of Pittsburgh
Metal-ceramic composites, electronic packaging, and environmental barrier coatings used for thermal protection, abrasion, and hot corrosion resistance are all made with metal/ceramic interfaces. Reliability of these interfacial materials relies heavily on the nature of their interface performance. Currently, moisture-induced interfacial embrittlement is one of major mechanical failures and becomes a serious technological concern in the application of these interfacial materials in moisture-containing environment. Lack of the understanding on (i) how moisture react with the metal/ceramic interfacial bonds and reduce the interfacial strength and (ii) what type of interface sensitive to moisture-induced embrittlement is the barrier for new interfacial materials (such as coatings and multilayers) design and application. This project will focus on the mechanism of moisture-induced ductile to brittle transition at interface through combined experiment and atomistic model prediction with in-situ X-ray photoelectron spectroscopy (XPS) test and first-principles calculations.
The proposed experiment with AFM tip/moisture/substrate interaction will open a new approach to quantify inter-atomic interaction with moisture effect. Furthermore, the project will integrate research and education by (i) providing training for graduate and undergraduate students, (ii) course development in ?interfacial materials and characteristics?, (iii) increased participation of underrepresented groups into the research through current Minority Engineering Mentoring Program, and (iv) outreach to elementary school and exposure of young students to interfacial materials and surface engineering through Internet explorers and Pittsburgh Carnegie Science Museum.
