Heterogeneity evaluation of research materials for microanalysis standards certification.
Electron microprobe testing and evaluation procedures to determine the extent of within- and between-specimen heterogeneity of reference materials and the experimental uncertainty are described. These procedures have been developed and used at NIST in the certification of several NIST Standard Reference Materials (SRMs). In this article, they have been simplified and updated for general use. Suggestions for experimental testing of specimens are described and a detailed description of the statistical evaluation process is included with an example of a data spreadsheet and instructions for its preparation.
Marinenko
Ryna
R
Surface and Microanalysis Science Division, Mail Stop 8371, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, MD 20899, USA. ryna.marinenko@nist.gov
Leigh
Stefan
S