Analysis of Nd Fe B in a Magnetic Materials using ICP-OES

As applications of Nd Fe B magnetic materials become more and more crucial, the quality of materials is more and more important. Not only has the quality of raw material to be considered but also the quality of intermediate and final products. Quality of products can be highly improved if analysis of raw materials can be performed as well as intermediate and final products. The production phase can also be shortened and thus its cost reduced.

High resolution ICP-OES is well suited for such application as it will help to solve all spectral interferences occurring to the line-rich spectrum emitted by Nd and Fe all over the spectral range. This application describes the analysis of many elements in Nd Fe B matrix.

Table 1. Characteristics of ULTIMA 2 ICP-OES Spectrometer

Optical mounting Czerny-Turner

Focal length 1 meter

Gratings Back-to-back gratings used in the 1st order4320 g/mm for 160 - 430 nm2400 g/mm for 430 - 800 nm

Resolution < 5 pm for 120 - 430 nm

< 10 pm for 430 - 800 nm

Thermoregulation 32 ± 0.1°C

RF Generator 40.68 MHz solid state, water cooled

Torch Vertical with Radial Viewing and Total plasma View*

* Total Plasma View: Measurement of the whole Normal Analytical Zone for enhanced sensitivity and reduced matrix effects

A concentric glass nebulizer and a cyclonic spray chamber were used to get the highest sensitivity. All details on the introduction system are given in Table 2.

Sample preparation

0.5g of sample was dissolved in 5 ml H2O and 5 ml HNO3 then volume was made up to 50 mL. All standard solutions for the external calibration were prepared using Spex CertiPrep single element standard solution.

Operating conditions

The characteristics of the ULTIMA 2 High Resolution spectrometer used for this study are given in Table 1. Note that this instrument is equipped with the dual grating system that improves resolution for Rare Earth Elements based applications.

Figure 1: ULTIMA 2 High Resolution ICP-OES

Explore the future Automotive Test Systems | Process & Environmental | Medical | Semiconductor | Scientific

ICPICP62

Material ScienceApplication Note

Li Zhaofen, HORIBA Scientific China, Shanghai

Dr. Matthieu Chausseau, HORIBA Jobin Yvon, 16-18 rue du canal, 91165 Longjumeau Cedex, France,

2

Explore the future Automotive Test Systems | Process & Environmental | Medical | Semiconductor | Scientific

Table 2. Specification of the sample introduction system

Nebulizer Glass Concentric

Spray chamber Glass cyclonic

Sample uptake 1 mL/min

Injector tube inner diameter 3 mm

Pump tubing Black-black pump tubing for sampleGrey-grey pump tubing for drain

All plasma parameters were optimized for sensitivity and robustness and are given in Table 3.

Table 3. Operating conditions

Power 1000 W

Plasma gas 12 L/min

Auxiliary gas 0 L/min

Sheath gas 0.3 L/min

Nebulizer flow 0.8 L/min (2.9 bars)

Pump speed 15 rpm

Acquisition was done using 3 replicates with Max mode and 2s integration time for analyte. A 20 µm / 15 µm slit combination was used for all lines.

Results

Line selection

Lines used are given in Table 4. Selection of lines was done after performing profiles on samples to identify potential spectral interferences.

Table 4: List of lines used for the analysis

Element Wavelength (nm) Element Wavelength (nm)

Al 396.152 Gd 336.224

B 208.959 Ho 345.600

Co 228.616 Nb 316.340

Cu 324.754 Nd 401.225

Dy 353.170 Pr 410.075

Fe 0259.94 Tb 350.917

Ga 417.206 Zr 339.198

Figure 1: Profile of Dy 353.170 nm.

Blue line: blank – white line: standard 2 mg/L – pink line: sample

Figure 2: Profile of Pr 410.065 nmBlue line: blank – white line: standard 2 mg/L – pink line: sample

Calibration

External calibration was performed for all lines with linear adjustment. Typical calibration curves obtained are shown in Figures 3 and 4 for Dy 353.170 nm and Fe 259.940 nm respectively.

Figure 3: Calibration curve for Dy 353.170 nm

Figure 4: Calibration curve for Fe 259.940 nm

3

Explore the future Automotive Test Systems | Process & Environmental | Medical | Semiconductor | Scientific

Results on samples

Results for all elements measured on Sample 1 and Sample 2 are given in Table 5. The measured values as well as the content in the original sample are given.

Table 5: Results obtained on samples 1 and 2

Sample 1 Sample 2

Elt Wavelength (nm)

Measu-red Conc. (mg/L)

Content in raw sample(%)

Mea-sured Conc. (mg/L)

Content in raw sample(%)

Al 396.152 10.0 1.000 6.82 0.682

B 208.959 8.92 0.892 9.78 0.977

Co 228.616 16.5 1.65 11.1 1.11

Cu 324.754 1.77 0.177 1.23 0.123

Dy 353.170 33.9 3.39 48.6 4.86

Fe 259.940 649 64.9 658 65.8

Ga 417.206 <0.05 <0.005 <0.05 <0.005

Gd 336.224 0.865 0.0865 0.0812 0.00812

Ho 345.600 3.74 0.374 0.524 0.0524

Nb 316.340 0.0577 0.00577 0.907 0.0907

Nd 401.225 231 23.1 244 24.4

Pr 410.075 40.6 4.07 13.5 1.35

Tb 350.917 0.194 0.0194 0.0797 0.00797

Zr 339.198 1.87 0.187 0.308 0.0308

Conclusion

The ULTIMA 2 allows measuring all elements for Nd Fe B applications, from trace to major, including rare earth elements. This makes the ULTIMA 2 High Resolution ICP-OES spectrometer the perfect instrument as this is the only instrument able to measure samples for Nd Fe B magnetic applications from raw material to final product.

info.sci@horiba.comwww.horiba.com/scientific

Thi

s do

cum

ent i

s no

t con

trac

tual

ly b

indi

ng u

nder

any

circ

umst

ance

s -

Prin

ted

in F

ranc

e -

©H

OR

IBA

Job

in Y

von

04/2

013

USA: +1 732 494 8660 France: +33 (0)1 69 74 72 00 Germany: +49 (0)89 4623 17-0UK: +44 (0)20 8204 8142 Italy: +39 2 5760 3050 Japan: +81 (0)3 6206 4721China: +86 (0)21 6289 6060 Brazil: +55 (0)11 5545 1500 Other: +33 (0)1 69 74 72 00