USE OF ANOMALOUS SMALL-ANGLE SCATTERING F OR ANALYSIS OF PHASE-SEPARATION OF TERNARY ALLOYS

Small Angle Scattering is a powerfull tool to study phase separation i n alloys. Nevertheless, standard X rays, sensitive to electronic densi ty fluctuations, are unable to differentiate the different elements in a ternary alloy. The Anomalous Scattering, through a resonance betwee n absorption and elastic scattering, changes the.atomic scattering fac tor of the given element and is therefore element selective. On exampl es borrowed to the study of phase separation in ternary alloys, severa l aspects of Small Angle Anomalous X-ray Scattering will be emphazised : discrimination between several interpretations, determination of pha se compositions or, more generally, of the spatial pattern for the thr ee elements through the formalism of Partial Structure Factors.