Log-normal nanograin-size distributions in nanostructured composites
A key challenge in the fabrication of superhard nanocomposite films is how to control the distribution of grain sizes in these materials. High-resolution transmission electron microscopy has been used to measure nanograin-size distributions in the Ti-B-N films with various B contents. The results sh...
| Main Authors: | , , , |
|---|---|
| Format: | Journal Article |
| Published: |
Taylor & Francis
2008
|
| Online Access: | http://hdl.handle.net/20.500.11937/15930 |
| Summary: | A key challenge in the fabrication of superhard nanocomposite films is how to control the distribution of grain sizes in these materials. High-resolution transmission electron microscopy has been used to measure nanograin-size distributions in the Ti-B-N films with various B contents. The results show that the mean grain size decreases with increase of B content and the grain-size distribution conforms to a log-normal function when the hardness approaches a maximum value. The transition from normal to log-normal distributions can be determined by analysis in terms of a minimum information criterion. The origin of a log-normal size distribution probably results from heterogeneity arising from a diffusion-drift process. |
|---|