Nanoniejednorodności materiałów a efekt małokątowego rozpraszania promieni rentgenowskich i neutronów

Abstract

The presence of nanoscale heterogeneities significantly affect the physical, chemical and mechanical properties of materials. This monograph focuses on the applications of small angle X-ray (SAXS) and neutron (SANS) scattering methods for the studies of such materials. The theoretical aspects of these methods for two-phase systems — that is the scattering object as well as the surrounding medium – are given. The effect obtained from different scattering systems is described. This systems involve the particle type as well as more complex, disordered ones. Investigation possibilities of SAXS and SANS methods for metallic materials and for porous materials are presented. The following metallic materials are analyzed: — precipitation hardened alloys on the aluminum, nickel, magnesium and iron matrices, — metallic glasses, — metals hardened by inert oxidation, — metals with defect structure, — electrodeposited metals. The methods based on the scattering effect are particularly applicable in the studies of porous materials owing to their intensive scattering effect. Moreover it is difficult to test them with the use of electron microscopy methods. The scattering effects from different porous silica materials as well as porous carbonation materials are analyzed. The heterogeneous catalysts studied using the anomalous small angle X-ray scattering (ASAXS) method are given as an example of the investigations of three- -phase materials.