27 research outputs found
Thermal Magnetoconductivity of Tungsten Below 6 K: Combining the Zero-, Low- and High-Field Cases
Atomic-resolution imaging of lattice imperfections in semiconductors by combined aberration-corrected HRTEM and exit-plane wavefunction retrieval
Direct observation of Lomer-Cottrell Locks during strain hardening in nanocrystalline nickel by in situ TEM
Nanoindentation properties and the microstructure of grain boundary precipitate-free zones (PFZs) in an AlCuSiGe alloy
We have characterized the nanoscale mechanical properties of grain boundary precipitate-free zones (PFZ's) in an AlCuSiGe alloy, using combined nanoindentation and in-situ atomic force microscopy (AFM). These mechanical properties were then correlated to the composition, precipitate distribution and, indirectly, to the vacancy concentration within these regions, as analyzed by transmission electron microscopy and spectroscopy. Using these results we constructed a structure-zone map of the area adjacent to the grain boundary, which relates the reduced elastic modulus and nanoindentation hardness of the alloy to its graded microstructure. Our analysis indicates that the lowest hardness was found in the region where no precipitates are present at all, regardless of solute concentration. In regions where precipitation is different from that of the bulk, somewhat inferior mechanical properties are achieved.close2