Recently the attention of many scientists has been attracted to nanostructured materials possessing novel physical and mechanical properties [1,2]. Nanoscale microstructures can form during processing of nanostructured materials using different methods, e.g. condensation in inert gas atmosphere, rapid quenching, electrodeposition, ball milling, severe plastic deformation and during oxidation (see [1,3]). Among them only severe plastic deformation and ball milling give bulk nanostructured samples while others yield thin films. It is well known that internal interfaces or the grain boundaries (GB) control behavior of nanostructured materials. Such properties as strength, ductility, hardness, resistnace to failure, corrosion resistance, fatigue and electromigration are all greatly affected by grain boundaries and their behavior as an whole ensemble [4-7]. Two major methods are used to characterize GB: transmission electron microscopy can analyze the atomic structure of individual grain boundaries and X-ray diffractometry may be used to examine volume-averaged characteristics. This paper presents a review of recent results obtained in ultra-fine grained (UFG), nanocrystalline (NC) metals, and oxide films using x-ray analysis. Both fine structure (crystallites' size, microdistortions) and statistical features (texture and grain boundary character distribution0 have been calculated from experimental measurements. Different techniques (severe plastic deformation, electrodeposition, oxidation etc.) have been used to process metals and alloys where mean grai nsize is less than 1 #mu#m for UFG and less than 100 nm for NC materials.
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