Structural materials microstructural changes

Nano-structures comments on an example of extreme microstructure In a chapter entitled Materials in Extreme States , Cahn (2001) dedicated several comments to the extreme microstructures and summed up principles and technology of nano-structured materials. Historical remarks were cited starting from the early recognition that working at the nano-scale is truly different from traditional material science. The chemical behaviour and electronic structure change when dimensions are comparable to the length scale of electronic wave functions. Quantum effects do become important at this scale, as predicted by Lifshitz and Kosevich (1953). As for their nomenclature, notice that a piece of semiconductor which is very small in one, two- or three-dimensions, that is a confined structure, is called a quantum well, a quantum wire or a quantum dot, respectively. 

There are two groups of monomers that can be activated by EB acrylate (radical) and epoxy (cationic). However, some resin systems would require additives, so-called photo initiators, to enable the resin system to respond in the required way. These photo initiators are special salts and could potentially change the material microstructure and also the mechanical performance. Therefore re-quaUfication of the material is required if it is to be used in primary structures. 

Wang, A. R, Chang, X. C., Hou, W. L. and Wang, J. Q. 2007. Preparation and corrosion behaviour of amorphous Ni-based alloy coatings. Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing, 449, 277-280. 

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