Quantitative analysis of high-temperature alloy steels on a Rigaku Simultix simultaneous WDXRF spectrometer

Industrial large-scale metal alloy production houses have a crucial need for immediate analytical results. These applications include both failure analysis for production issues and general quality/process control. The need for fast, accurate, and precise analyses for industrial metallic applications is met with the Rigaku Simultix, a simultaneous wavelength-dispersive X-ray fluorescence (WDXRF) spectrometer. The total analysis time for the high-temperature alloy application below was less than one minute due to the speed-minded geometry in the dedicated analysis channels on a simultaneous WDXRF spectrometer.

The standards listed in Table 1 were used to generate a quantitative calibration method, based on Rigaku's Fundamental Parameters, to analyze a high temperature alloy metallic product.

High-temperature alloys: NBS(NIST) 1184, 1185, 1187, 1189
High-temperature alloys: NBS(NIST) 1207-1, 1207-2, 1208-1, 1208-2
High-temperature alloys: JAERI R2, R5, R6, R7
High-temperature alloys: Stainless steels: JSS JSS650-11, JSS651-11, JSS652-11, JSS653-11, JSS654-11, JSS655-11
High-temperature alloys: Stainless steels: NBS(NIST) D845, D846, D847, D848, D849, D850
High-temperature alloys: Austenite stainless steel: BAS BAS61, BAS62, BAS63, BAS64, BAS65, BAS66, BAS67, BAS68

Table 1



The high degree of accuracy achievable with a quantitative calibration of this scale can be seen in Table 2 for the entire major, minor, and trace analyte suite in a high-temperature alloy steel.

Element
Concentration range
Accuracy
(σ d mass%)
Mn
0.082-2.13
0.03
Si
0.075-1.42
0.02
Cr
2.99-25.6
0.08
Ni
0.28-74.2
0.11
Co
0.011-20.8
0.04
Mo
0.014-4.5
0.01
W
0.04-2.40
0.01
Nb
0.001-5.38
0.01
Ti
0.001-3.09
0.02
Al
0.005-1.39
0.03
Fe
1.40-85.5
0.17
P
0.001-0.035
0.003
S
0.002-0.028
0.002
Cu
0.0031-0.39
0.008
Ta
0.001-0.048
0.008

Table 2

The analytical precision has also been calculated based upon a 10 run repeatability routine, and displayed in Table 3 for all 15 elements.

Element
Typical value
(mass %)
Standard
deviation
(σ d Mass%)
Coefficient of
variance
(C.V. %)
Mn
0.81
0.0005
0.06
Si
0.92
0.0009
0.10
Cr
20.3
0.005
0.02
Ni
72.6
0.005
0.007
Co
0.06
0.0002
0.28
Mo
0.05
0.0003
0.55
Nb
4.98
0.0016
0.03
Ti
2.52
0.001
0.04
Al
1.21
0.0015
0.14
Fe
1.40
0.002
0.14
P
0.003
0.00013
2.62
S
0.007
0.0002
1.63
Cu
0.077
0.0002
0.28
Ta
0.012
0.0009
6.00

Table 3

In summation, the high degree of accuracy (down to 200 ppm) and the stability demonstrated in the precision statistics (not greater than 1.6 % C.V. except in extreme traces like Ta) efficiently demonstrates the superior ability to get a fast (under 1 minute total analysis time), reliable high-temperature metal alloy analysis on a simultaneous WDXRF spectrometer like the Rigaku Simultix, through a fundamental parameters-based quantitative calibration routine.