Homogeneity studies in some standard reference materials

Ion beam analysis techniques have some specific problems which make quantification of the results very difficult. Of those problems associated with microanalysis is lack of suitable standard reference materials. Because reference materials should also be checked for homogeneity to satisfy the demands of a microanalysis set up with respect to accuracy. Homogeneity is one of the basic requirements for a candidate reference material. In this study several powder standard reference materials such as soil 7, SL-1, A-13, V-10, A-11 and MA-B-3/TM were used to check the homogeneity requirements or test for reliability. Proton Induced X-ray Emission technique was employed as the homogeneity evaluation method, since it needs minimal preliminary sample preparation and is capable of determining a number of elements simultaneously with high sensitivity and good precision. Specific experimental conditions such as beam intensity, beam diameter and its energy are kept constant during the course of the work. The results of compositional analysis of samples have been compared with available data. Finally, discussion of the results is next. (author)