Broader Impact:

1. Transitional creep mechanisms in textured low c/a-ratio hcp metals under biaxial loadingK. Linga Murty, North Carolina State University, DMR 0968825 HANA4 alloy which is Zircaloy-4 with 0.8%Nb was received in cold-worked stress-relieved form and OIM microstructures are illustrated on the right along with inverse pole figure. Biaxial creep tests were performed under closed-end internal pressurization biaxial stress (sq=2sz) at two different temperatures as a function of stress (Figure on right top). Results depicted the alloy class behavior with typical n=3. In order to achieve lower stress levels, further studies will be made after complete recrystallization. Effect of annealing temperature on hardness as revealed in Figure was evaluated by an REU student (Mr. Jamie Skovron) during summer 2012 mentored by graduate student, Mr. Boopathy Kombaiah.

2. Transitional creep mechanisms in textured low c/a-ratio hcp metals under biaxial loadingK. Linga Murty, North Carolina State University, DMR 0968825 • Broader Impact: • Zirconium-based alloys find applications in nuclear industry as thin-walled tubing to clad highly radioactive UO2 fuel. The research will is directed to an understanding of the creep behavior of these cladding tubes under applied biaxial loading by internal pressurization with emphasis on transitions in creep mechanisms as lower stresses are encountered that are representative of in-reactor conditions. • As a part of ‘Young Investigators Summer Programs’ since 2006, groups of high school students were involved in a two-week long research project assisted by the graduate students supported by this grant. After completion of their project, they presented their research results. This is an ideal way to recruit bright students to science and technology. • A student from Florida Central University worked on burst characteristics of Zircaloy tubing (Figure below right) supported by an REU grant in Materials Science & Engineering department during this summer. Photo on left shows the group of 4 high school students along with the REU student (in the back), the PI and graduate students and a post-doctoral fellow.