scholarly journals Successive Grinding and Polishing Effect on the Retained Austenite in the Surface of 42CrMo4 Steel

Metals ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 119
Author(s):  
Jiří Pechoušek ◽  
Ernö Kuzmann ◽  
René Vondrášek ◽  
Anna Olina ◽  
Vlastimil Vrba ◽  
...  
Keyword(s):  
Mössbauer Spectroscopy ◽  
Retained Austenite ◽  
Mossbauer Spectroscopy ◽  
Surface Preparation ◽  
Large Decrease ◽  
X Ray ◽  
Austenite Content ◽  
Mößbauer Spectroscopy ◽  
Unique Method ◽  
Grinding And Polishing

Low-alloy 42CrMo4 steels were studied by 57Fe Mössbauer spectroscopy (MS), X-ray diffractometry (XRD), and Energy Dispersive X-ray Spectroscopy (EDS) measurements. The investigations were performed on metallographic samples, which were subjected to a series of successive grinding and polishing with a progressively finer grit. Conversion X-ray Mössbauer spectroscopy (CXMS) was used to determine the occurrence of austenite in steel samples. It is a unique method detecting the austenite content very sensitively. Six samples with different surface preparation were investigated, starting with 4.8% of austenite on an as-cut sample, and a large decrease in the retained austenite to 2.6% was observed after the first grinding of a hardened cut sample. Additionally, an unexpectedly large decrease in the austenite content to 2.3% was found due to the final polishing. A second time applied successive grinding and polishing of all samples resulted in identical austenite content determined by CXMS of approx. 5%, which proved the applicability of the CXMS method. Generally, the result calls attention to the importance of preparation of metallurgical samples by grinding and polishing where the results can vary significantly on the level of surface processing.

The Mössbauer Spectroscopy and X-Ray Diffraction Studies of Phase Transformation during Tempering in High-Carbon Tool Steel

2010 ◽  
Vol 163 ◽  
pp. 200-203 ◽  
Author(s):  
P. Bała ◽  
J. Krawczyk ◽  
Artur Hanc ◽  
Grzegorz Dercz
Keyword(s):  
Mössbauer Spectroscopy ◽  
Retained Austenite ◽  
Mossbauer Spectroscopy ◽  
X Ray Diffraction ◽  
High Carbon ◽  
Spectroscopy Technique ◽  
Iron Carbides ◽  
X Ray ◽  
Mößbauer Spectroscopy ◽  
Tempering Time

This work presents the results of investigations using Mössbauer spectroscopy technique and XRD, and their interpretation concerning precipitations and transformation of iron carbides and retained austenite stabilization. It also discusses changes in hardened matrix during tempering in relation to previously conducted dilatometric, microscopic and mechanical examinations. This research was carried out using a new high-carbon alloy 120MnCrMoV8-6-4-2 steel, which was designed in 1998, in Phase Transformations Research Group at the AGH UST. The influence of the tempering time on the mechanical and chemical stability of retained austenite and on the products of its transformation, nucleation and solubility of iron carbides and cementite nucleation and growth, was determined.

The Comparative Study of Phase Composition of Steels Using X-Ray Diffraction and Mössbauer Spectroscopy Methods

2013 ◽  
Vol 203-204 ◽  
pp. 150-155
Author(s):  
Piotr Pawluk ◽  
Emilia Skołek ◽  
Michał Kopcewicz ◽  
Wiesław Świątnicki
Keyword(s):  
Mössbauer Spectroscopy ◽  
Phase Composition ◽  
Retained Austenite ◽  
Mossbauer Spectroscopy ◽  
Rietveld Method ◽  
Bainitic Ferrite ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mößbauer Spectroscopy ◽  
Diffraction Patterns

In this paper phase composition of several steels was investigated by X-ray diffraction and conversion electron Mössbauer spectroscopy (CEMS) methods. Different heat treatments were performed on steel samples in order to obtain various phase compositions (containing bainitic ferrite, martensite and retained austenite). The diffraction patterns were analysed using the Rietveld method. Mössbauer spectra were fitted and studied for existent phases. A comparison between results obtained by each method was performed. Both methods revealed some supersaturation of carbon in the retained austenite and in the bainitic ferrite phases, various after different treatments. The quantitative phase composition measured by X-ray diffraction results differ significantly from the Mössbauer spectroscopy results. The possible reasons of the observed differences were discussed.

Nature and mechanism of ilmenite alteration: a Mössbauer and X-ray diffraction study of oxidized ilmenite from the Beja-Acebuches Ophiolite Complex (SE Portugal)

2002 ◽  
Vol 66 (3) ◽  
pp. 421-430 ◽  
Author(s):  
J. C. Waerenborgh ◽  
J. Figueiras ◽  
A. Mateus ◽  
M. Gonçalves
Keyword(s):  
Mössbauer Spectroscopy ◽  
Mossbauer Spectroscopy ◽  
X Ray Diffraction ◽  
Ophiolite Complex ◽  
Cation Site ◽  
X Ray ◽  
Mößbauer Spectroscopy ◽  
Ilmenite Structure ◽  
Optical Evidence ◽  
Excess Fe

AbstractIlmenites from the least-altered rocks of the Beja-Acebuches Ophiolite Complex (SE Portugal), with low Ti values and excess Fe, despite rare optical evidence of hematite exsolution, were studied by 57Fe Mössbauer spectroscopy and X-ray diffraction. According to single-crystal XRD the sequence of alternate layers characteristic of the ideal ilmenite structure is preserved, the excess Fe being accommodated in the Ti layers. No superparamagnetic oxides were detected by 57Fe Mössbauer spectroscopy. The typical spectra of bulk αFe2O3 and of Fe3+-containing ilmenite, in the paramagnetic state above 49 K and magnetically ordered at 6 K, are observed. The average degree of oxidation of the ilmenites, estimated from the chemical analysis assuming ideally stoichiometric full cation site occupancies, is also confirmed by 57Fe Mössbauer data. Since our crystal chemistry study gave no evidence of crypto-exsolution textures within the ilmenite with the observed compositions, fast cooling from magmatic temperatures and decomposition of ilmenite in supergene conditions is suggested.

A Study of Aluminum-Substituted Iron Dextran Complexes by Mössbauer Spectroscopy and X-ray Diffraction

2001 ◽  
Vol 13 (1) ◽  
pp. 136-140 ◽  
Author(s):  
Tianrong Cheng ◽  
Robert Bereman ◽  
Eddy De Grave ◽  
Larry H. Bowen
Keyword(s):  
Mössbauer Spectroscopy ◽  
Mossbauer Spectroscopy ◽  
Iron Dextran ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mößbauer Spectroscopy

Microstructure Evolution and Mossbauer Spectroscopy Research of Nanostructured Ni3 Fe Intermetallic

2021 ◽  
Vol 32 ◽  
pp. 1-13
Author(s):  
Amel Kaibi ◽  
Abderrahim Guittoum ◽  
Nassim Souami ◽  
Mohamed Kechouane
Keyword(s):  
Magnetic Field ◽  
Mössbauer Spectroscopy ◽  
Mössbauer Spectra ◽  
Milling Time ◽  
Mossbauer Spectroscopy ◽  
Hyperfine Magnetic Field ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mossbauer Spectra ◽  
Mößbauer Spectroscopy

Nanocrystalline Ni75Fe25 (Ni3Fe) powders were prepared by mechanical alloying process using a vario-planetary high-energy ball mill. The intermetallic Ni3Fe formation and different physical properties were investigated, as a function of milling time, t, (in the range 6 to 96 h range), using X-Ray Diffraction (XRD) and Mössbauer Spectroscopy techniques. X-ray diffraction were performed on the samples to understand the structural characteristics and get information about elements and phases present in the powder after different time of milling. The refinement of XRD spectra revealed the complete formation of fcc Ni (Fe) disordered solid solution after 24 h of milling time, the Fe and Ni elemental distributions are closely correlated. With increasing the milling time, the lattice parameter increases and the grains size decreases. The Mössbauer experiments were performed on the powders in order to follow the formation of Ni3Fe compound as a function of milling time. From the adjustment of Mössbauer spectra, we extracted the hyperfine parameters. The evolution of hyperfine magnetic field shows that the magnetic disordered Ni3Fe phase starts to form from 6 h of milling time and grow in intensity with milling time. For the milling time more than 24 h, only the Ni3Fe disordered phase is present with a mean hyperfine magnetic field of about 29.5 T. The interpretation of the Mossbauer spectra confirmed the results obtained by XRD.

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