RESUMEN
TiN-Ag nanocomposite was synthesized by dc arc-plasma method. Microstructures of TiN-Ag nanocomposite were carefully characterized by powder X-ray diffraction method and transmission electron microscopy, and nano-morphologies by three-dimensional electron tomography. It was found that the surface of nanocrystalline TiN matrix was densely covered by finely dispersed Ag nanoparticles, and it was found that they were physically attached but not chemically bonded from their orientation relationships.
Asunto(s)
Conformación Molecular , Nanocompuestos , Nanotecnología/métodos , Plata/química , Titanio/química , Cristalización/métodos , Electroquímica , Tomografía con Microscopio Electrónico , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Microscopía Electrónica de Transmisión , Nanocompuestos/química , Nanocompuestos/ultraestructura , Compuestos de Plata/química , Difracción de Rayos XRESUMEN
The growth mechanism and morphology of Ge precipitates in an Al-Ge alloy was characterized by a combination of in-situ transmission electron microscopy, high-resolution transmission electron microscopy and three-dimensional electron tomography. Anisotropic growth of rod-shaped Ge precipitates was observed by in-situ transmission electron microscopy over different time periods, and faceting of the precipitates was clearly seen using high-resolution transmission electron microscopy and three-dimensional electron tomography. This anisotropic growth of rod-shaped Ge precipitates was enhanced by vacancy concentration as proposed previously, but also by surface diffusion as observed during the in-situ experiment. Furthermore, a variety of precipitate morphologies was identified by three-dimensional electron tomography.