Quantitative EDS analysis - an example printout
The EDX option of an SEM can be used for quick and convenient quantitative analysis. Sometimes it is one of several analytical methodes, in other cases it is the only means to get results. In the example shown on this page a sample of granulated catalysator parts has been investigated. A fraction of highly magnetically susceptible particles of light ashes has been collected and analysed. This fraction shows a rather high content of Fe2O3.
Spectrum file : KATA14
catalysator, sample A, fraction highly magnetically susceptible, 5qmm LIVETIME(spec.)= 200
ENERGY RES AREA
- 2.1 69.44 140308
TOTAL AREA= 130865
...
FIT INDEX= .59 the program fits standard spectra to the sample spectrum,
then calculates the quality of the fit and a first approximation
ELMT APP.CONC ERROR(WT%) of the concentrations, that have to be refined afterwards
MgK : 0 .139 .040
AlK : 0 1.067 .043
SiK : 0 1.624 .057
S K : 0 3.515 .081
K K : 0 1.642 .052
CaK : 0 .424 .041
TiK : 0 7.238 .097
V K : 0 .098 .060* < 2 Sigma* * vanadium is found to be below detection limit
FeK : 0 4.709 .124
W M : 0 .825 .143
AuM : 0 2.767 .163Not used for quantitation lines listed left are not necessary for quantitation
AuL : 0 4.478 .483Not used for quantitation because they for instance represent sputter material
CuK : 0 .311 .103Not used for quantitation
CuL : 0 .112 .183* < 2 Sigma*Not used for quantitation
W L : 0 .758 .253Not used for quantitation
ZAF CALCULATIONS the iterative procedure of the refinement starts
..[ 2 iterations]
20.00 kV TILT=20.00 ELEV=20.00 AZIM=45.00 COSINE=1.000 the analytical conditions used are stated here
catalysator, sample A, fraction highly magnetically susceptible, 5qmm
Last elmt by STOICH.,NORMALISED in this case oxygen has been calculated from stoichiometry
ELMT ZAF %ELMT +- Error ATOM.% %OXIDE FORMULA the final results:
MgK : 0 .579 .544 +- .156 .554 MgO .902 .100 the calculated error is for
AlK : 0 .693 3.488 +- .141 3.198 Al2O3 6.590 .580 the stochastism of X-ray generation
SiK : 0 .775 4.746 +- .167 4.180 SiO2 10.152 .757 and overlap of X-ray lines
S K : 0 .857 9.286 +- .215 7.166 SO3 23.189 1.299
K K : 0 1.017 3.660 +- .115 2.316 K2O 4.409 .420
CaK : 0 .997 .964 +- .094 .595 CaO 1.349 .108
TiK : 0 .869 18.881 +- .254 9.751 TiO2 31.494 1.767
V K : 0 .866 < .120 +- .060 for vanadium the respective detection
FeK : 0 .858 12.440 +- .326 5.510 Fe2O3 17.785 .999 limit has been calculated
W M : 0 .642 2.913 +- .505 .392 WO3 3.673 .071
O K : 0 .000 42.824 66.214 12.000
TOTAL 99.745 100.000 99.545 6.100