Nanocrystalline zinc oxides are produced by chemical vapor synthesis and characterized by x-ray diffraction, high resolution transmission electron microscopy, nitrogen sorption, and extended x-ray absorption fine structure. Dopant elements aluminum, gallium, and indium influence the particle size of the powders as well as lattice parameters and local structure. The different effects of the thre...

In nanocrystalline metals, lack of intragranular dislocation sources leads to plastic deformation mechanisms that substantially differ from those in coarse-grained metals. However, irrespective of grain size, plastic deformation is considered irrecoverable. We show experimentally that plastically deformed nanocrystalline aluminum and gold films with grain sizes of 65 nanometers and 50 nanometer...

At the beginning of the present century it has been demonstrated that nanocrystalline titanium (NC-Ti) can be fabricated by hydrostatic extrusion (HE) which is one of the severe plastic deformation method. NC-Ti obtained in such a way exhibited excellent mechanical properties. The influence of HE on the microstructure and mechanical properties of titanium Grade 2 was first analyzed in 2005. In ...

The purpose of this research is to develop an optimal method for synthesizing of nanocrystalline Al2O3 monolayers at high growth rates on cemented carbides coated with an intermediate layer of pre-Al2O3-C (composite layers Al2O3-C/Al2O3). The use of quartz glass substrate allows for obtaining information about the quality of the layers such the thickness and density, because of its high transpa...

Conventionally, mean grain size is considered the most critical microstructural parameter in determining the mechanical behavior of pure metals. By systematically controlling the distribution of grain orientations in aluminum films, we show that microstructural heterogeneity alone induces large variation in the mechanical behavior of nanocrystalline metal films. Aluminum films with relatively h...

The influence of high energy-ball milling (HEBM) on corrosion and hardness age hardening aluminum alloys was investigated. Nanocrystalline (AA2024, AA6061 AA7075) were produced by HEBM pre-alloyed powder subsequent cold compaction under uniaxial pressure 3 GPa. Cyclic potentiodynamic polarization immersion tests conducted in 0.6 M NaCl solution which revealed significantly increased pitting pro...

Recent progress in atom probe field ion microscopy (APFIM) and its applications to nanoscale microstructural studies of metallic materials are reviewed. By employing a three dimensional atom probe (3DAP), it is possible to map out elemental distributions in the real space with almost an atomic resolution, and chemical analysis of interfaces and nanoparticles can be made with improved accuracy i...