A preliminary study of the insitu heating behavior of single- crystal cubes of 100-300 nm MgO smoke particles has shown that the stability of neck formed between 2 sintering single-crystal cubes is directly related to the contact geometry of the particles. This research project is a logical extension of the initial MgO cube study. It will focus on the following objectives: determination of the specific mechanism(s) responsible for mass transport in vacuum heated, sub-micron-sized MgO single crystal cubes; insitu TEM heating studies of coalescence and material transport in isolated pairs of nanoscale, single crystal, spherical particles of ceramic oxides; insitu heating studies of larger arrays of nanoscale particles; and exsitu heating studies to examine the effects of the sintering atmosphere on neck morphology and stability. The neck instabilities observed in the preliminary studies have never before been observed or predicted. This research will develop our understanding of this phenomena, and further insitu experiments are likely to lead to additional new insights into the sintering of fine particles. Interactive activities at the host institution include: organizing and teaching two new courses (one course will study noncrystalline solids by examining both bulk and thin-film glasses, and the other course will be an engineering/technology survey course for non- engineers, based on materials science topics); and participation as a discussion leader in Women in Science and Engineering, an organization for women undergraduates. This project furthers VPW program objectives which are (1) to provide opportunities for women to advance their careers in engineering and in the disciplines of science supported by NSF and (2) to encourage women to pursue careers in science and engineering by providing greater visibility for women scientists and engineers employed in industry, government, and academic institutions. By encouraging the participation of women in science, it is a valuable investment in the Nation's future scientific vitality.
