Contact us: +420 734 265 043 | petr.kubecka@upol.cz

Austenitemeter
detector of austenite


Share the experiences of researchers from Palacký University Olomouc on non-destructive analysis of iron containing materials.


The instrument is currently being used in daily mode at the steel producer TŘINECKÉ ŽELEZÁRNY, a. s. (Třinec, Czech Republic).

About Austenitemeter

Austenitemeter is a brand new portable device based on Mössbauer spectroscopy. It allows non-destructive and rapid determination of austenite or other iron-phases content in steel. This non-destructive measurement method enables austenite determination even for structures in use without their removing or cutting in just 20+ minutes. The thickness of the analyzed layer is up to approx. 10 µm, the most effective thickness is 5 µm.

In high precision mode it allows detailed phase analysis (iron-bearing phases).


„For the needs of industry we optimized the laboratory analytical tool. Our device will help engineers to accelerate their work by enhacing the precision of samples, structures, or machinery on location analysis.“

Jiří Pechoušek, Leading scientist


Benefits for You

precision mode for detailed phase analysis

fast analysis in 20+ minutes with 2% accuracy (in optimal sample arrangement)

precise analysis with 1% accuracy (long term)

portable for on-site measurement

non-destructive precise analytical tool

phase composition

utility model IP protection

suitable for metallurgy, engineering, material research, archeology, autentification



Principle of measurement.

[Ref. 3]

Principle of analysis.


Technical specifications

low energy radioactive source 57Co

(25mCi or 50 mCi activity)

6.4 keV X-ray gas detector

weight 11 kg

45 cm high, 30 cm wide incl. rails

Examples

Why to use Mössbauer spectroscopy?

Why to use Mössbauer spectroscopy?

Mössbauer spectroscopy is a nuclear analytical tool for material research. The results obtained by Mössbauer spectroscopy show high resistance to the arrangement, preparation, and macroscopic texturing of the sample. Since both paramagnetic and magnetic phases (austenite – ferrite) are well distinguished in the Mössbauer spectra, it is possible to perform basic evaluation of retained austenite in a fast way. Taking into consideration that alloying elements and significant amounts of retained austenite exhibit more complex Mössbauer spectra, they need to be analyzed by more precise approach. In basic concept, all magnetic phases that exhibit sextet (including the martensite as a supersaturate solution of carbon in ferrite) are assigned to the ferritic phases. This method is nondestructive and could find a wide application in industrial use. In the precise mode the method is able to distinguish all iron-bearing phases (ferrites, oxides, carbides, etc.).

Mössbauer spectroscopy is a nuclear resonance spectroscopic technique based on the nuclear emission and resonant absorption of gamma rays. This experimental technique provides qualitative and quantitative analysis of materials (e.g., structural, phase, and magnetic information) containing specific elements. The 57Fe isotope shows the most favorable parameters for Mössbauer spectroscopy. Backscattering geometry allows to analyze surfaces of bulk materials. Hence, 57Fe Mössbauer spectroscopy is considered as crucial experimental method in steel characterization. Scattering method utilizes the conversion X-rays registration which analyzes material surface up to the depths of 1–20 µm.

Mössbauer spectroscopy employes electric and magnetic hyperfine interactions between electrons of the iron atom and Mössbauer-active nucleus (in the source). The hyperfine parameters are isomer shift, quadrupole splitting, and hyperfine magnetic splitting. The isomer shift is a result of the Coulomb interaction between nuclear/nuclei charge and electrons charge. The charges distributed asymmetrically around the atomic nucleus (electrons, ions, and dipoles) increase the electric field gradient, which differs from zero on the site of nucleus. These electric quadrupole interactions cause a splitting of the excited nuclear level and provide information about bond properties and the local symmetry of iron site. The third hyperfine parameter is magnetic splitting. This magnetic field can originate within the atom itself, within crystals via exchange interactions, or it can be external one. The magnetic field (nuclear Zeeman effect) splits the nuclear states.

References:

  1. Olina, A.; Píška, M.; Petrenec, M.; Hervoches, C.; Beran, P.; Pechoušek, J.; Král, P.: Assessment of Retained Austenite in Fine Grained Inductive Heat Treated Spring Steel, Materials 12(24)4063, doi:10.3390/ma12244063
  2. Pechoušek, J.; Kouřil, L.; Novák, P.; Kašlík, J.; Navařík, J.: Austenitemeter – Mössbauer spectrometer for rapid determination of residual austenite in steels, Measurement 131, 671–676, doi:10.1016/j.measurement.2018.09.028
  3. Kouřil, L.; Pechoušek, J.; Novák, P.; Navařík, J.; Kohout, P.: Toroidal proportional gas flow counter for conversion X-ray Mössbauer spectroscopy, Nuclear Instruments and Methods in Physics Research B 432, 55–59, doi:10.1016/j.nimb.2018.07.020
  4. Pechoušek, J.; Kuzman, E.; Vondrášek, R.; Olina, A.; Vrba, V.; Kouřil, L.; Ingr, T.; Král, P.; Mašláň, M.: Successive Grinding and Polishing Effect on the Retained Austenite in the Surface of 42CrMo4 Steel, Metals 12(1)119, doi:/10.3390/met12010119