MECHANICAL CHARACTERIZATION OF SN AND SHAPE MEMORY ALLOY INTL NANOWIRES AS PART OF AN UNDERGRADUATE RESEARCH EXPERIENCE
This paper provides a description of an undergraduate student's summer project and an analysis of his overall learning and research experience, which took place during the summer of 2011. The first author, who was the undergraduate student, was supported by a summer research grant. One of the goals of this grant was to prepare students for graduate study and research. The student participated in an inclusive learning community of graduate students, postdoctoral associates, university faculty, and undergraduate researchers from the host university and from other universities. Student activities included preparation of research plans, weekly presentations to multidisciplinary research groups, preparation of progress reports and research papers, and research poster presentation. The student learned to operate state of the art laboratory equipment, such as scanning electron microscopes, energy dispersive spectroscopes, and nano-indenters, and computational software such as ABAQUS finite element analysis (FEA) simulation software. During the course of this project, a number of seminars focusing on research-based careers and graduate school opportunities were presented by leading faculties of the university. The goal of the research work undertaken by the undergraduate student was to characterize the mechanical properties of Sn and shape memory alloy indium-thallium (InTl) nanowires embedded into cylindrical pores arranged along the thickness direction of anodic aluminum oxide (AAO) films. A broad range of nanotechnology applications requires one-dimensional nanostructures such as nanowires. Before any feasible application, the mechanical properties of such structures need to be characterized. The AAO films with constant pore diameter were fabricated using a two-step anodization. Molten Sn or InTl was injected into cylindrical pores of the AAO films to form the composites. Nanoindentation was performed on bulk Sn, bulk InTl, AAO films at different steps of the composite fabrication, and the finished composites. The force-displacement curves from the nanoindentation tests were analyzed to characterize the elastic properties of the specimens. The results showed that the indentation modulus of the AAO films decreased after heating and pressing of the films during the fabrication process. The reasons may be formation of nanocracks due to thermal and compressive stresses during heating and pressing of the films, respectively. The indentation modulus of the composites was lower than the bulk metals and the AAO films with empty pores. This may be due to nanocracks formed on the AAO film during the crystallization of the metal inside the pores. 2012 American Society for Engineering Education.