EDAX Spectrum Match is a robust software tool that automatically searches a custom-built spectrum library to identify and match spectra with similar profiles. Comparing an unknown to a group of possible candidates makes identification effortless and makes it easier to identify differences and similarities between spectra.
The Chi-squared goodness of fit statistical method, which compares either concentrations or spectra lines directly, is used to match an unknown spectrum to possible library candidates. The matching sensitivity can be changed and match outcomes can be completely controlled for the appropriate level of confidence.
The original spectrum is superimposed with the possible matching spectra. The match percentage illustrates the differences between the spectra and quantifies how similar or dissimilar they are.
There are 150 entries of common metal standard alloys and minerals in the EDAX Smart Materials and Minerals Library option. The included 90 steel spectra comprise:
- Stainless steels
- Alloy steels, alloys based on nickel and copper
- Carbon steels
- Tool steels
More than 50 silicates and other geologically standard materials for identifying environmental and mineralogical components are also available in the library.
The library is used to display the top three matches for the unknown sample along with a spectral overlay that verifies the details of the spectral peak fit, along with numerical values of the goodness of fit percentage.
The quantification numbers are less sensitive to variations in acceleration voltage, geometry, and detector characteristics. Spectrum Match is the quickest method for obtaining definitive material characterization solutions, even when peak overlaps are causing interference.
Figure 1. Spectrum extracted from the map visibly and numerically identifies this phase as SbS with a much higher fit % than CaSO4 even though they contain common elements despite the challenging Sb and Ca peaks. Image Credit: AMETEK Gatan, Inc.