Nanostructure Image Gallery
3D elemental map of Bulk Insulator Ceramics

Contrary to the popular belief that bulk insulators cannot be analyzed by the atom probe technique, we have demonstrated that atom probe analysis of bulk insulating ceramics is possible by using ultraviolet femtosecond pulse laser. For the demonstration, spark plasma sintered yttria-stabilized ZrO2-MgAl2O4 nanocomposite material was used. Needle like specimens for field ion microscopy and atom probe analysis were prepared from the bulk sample using the focused ion beam technique. Three dimensional elemental distributions from both the zirconia and spinel have clearly demonstrated that the laser assisted field evaporation yield quantitative atom probe tomography. Atom probe tomography of Al (green) and Mg (blue) atoms with a volume of ~65×65×270 nm3. The grain boundary segregation of Al and Mg can be clearly seen on the right-hand side. © Y.M. Chen, T. Ohkubo, M. Kodzuka, K. Morita and K. Hono, 2009
3D elemental map of Nd-enriched grain boundary in a Dy-diffused Nd-Fe-B sintered magnet

The above 3DAP elemental map shows the distributions of Nd (green), Ga (purple), and Cu (blue) atoms. A grain boundary can be clearly visible from the difference in the orientation of the lattice planes. The grain boundary is enriched with Nd, Ga and Cu. Both Cu and Ga are segregated at the interfaces between the Nd-rich grain boundary phase and the Nd2Fe14B grains. © H. Sepheri-Amin, T. Ohkubo and K. Hono, 2010















