Atomic short-range order in mechanically synthesized iron based Fe-Zn alloys studied by ⁵⁷Fe Mössbauer spectroscopy

Abstract

Abstract. Mechanical alloying method was applied to prepare nanocrystalline iron-based Fe 1−x Zn x solid solutions with x in the range 0.01  x  0.05. The structural properties of the materials were investigated with the Mössbauer spectroscopy by measuring the room temperature spectra of 57 Fe for as-obtained and annealed samples. The spectra were analyzed in terms of parameters of their components related to unlike surroundings of the iron probes, determined by different numbers of zinc atoms existing in the neighborhood of iron atoms. The obtained results gave clear evidence that after annealing process, the distribution of impurity atoms in the fi rst coordination spheres of 57 Fe nuclei is not random and it cannot be described by binomial distribution. The estimated, positive values of the short-range order parameters suggest clustering tendencies of Zn atoms in the Fe-Zn alloys with low zinc concentration. The results were compared with corresponding data derived from Calphad calculation and resulting from the cellular atomic model of alloys by Miedema.

Thermodynamic Properties of Dilute Fe-Ge Alloys Studied by the 57Fe Mössbauer Spectroscopy

“…The TMS technique is especially powerful when the appearance of impurity atoms in the vicinity of the Mössbauer probe have a sufficiently large effect on the hyperfine field generated at the probe, to yield distinguishable components in the Mössbauer spectrum. Basing on the distributions of iron atoms in the studied materials, which is related to the intensities of the Mössbauer spectrum components one can determine for example the shortrange order (SRO) parameter [13,14], the binding energy E b between two impurity atoms [15] and the enthalpy of solution H Fe-D of elements -D in the ferromagnetic * corresponding author; e-mail: robi@ifd.uni.wroc.pl matrix [16]. These last one is widely used in developing and testing different models of binary alloys as well as methods for calculating the alloy parameters [8][9][10].…”

Metallurgical quality evaluation of the wind turbine main shaft 42CrMo4 steel: microscopic and Mössbauer studies

“…The novelty of the presented work is the application of the Mössbauer spectrometry to the atomic structure studies of wind Metallurgical quality evaluation of the wind turbine main shaft 42CrMo4 steel: microscopic and Mössbauer studies turbine shaft. This technique (complementary to optical microscopy and spark spectrometry as well as X-ray diffraction (XRD)) enables the qualitative and quantitative phase analysis of the materials [10][11][12][13][14][15][16][17][18]. Mössbauer spectrometry based on 57 Fe isotope is very effective tool for the material quality investigations of various types of steel, e.g.…”

“…high--carbon tool steel [10], cold drawn eutectoid steel [11], AISI 1137 type steel [12], nitrided cast steels [13], plasma-nitrided carbon steel [14], as well as corrosion products on steel [15], or the structure of friction products and the surface of tribological system elements [16]. The method even proved to be a useful tool for the study of the atomic short-range order in alloys [17] and interactions of impurity atoms dissolved in iron [18].…”

Mössbauer study of Fe-Re alloys prepared by mechanical alloying

“…On the other hand the controlled thermal treatment of mechanically alloyed products combined with a structural investigation allow determining the structural stability of the materials. Monitoring of mechanical alloying can be performed by many different techniques, in particular by Mössbauer spectroscopy delivering information on, for example, the processes of the formation of the dilute solid solutions as well as structural changes, phase transformations, magnetic and thermodynamic properties of the materials [5][6][7][8][9][10][11]. In general, the Mössbauer spectroscopy is especially powerful when the appearance of impurity atoms in the vicinity of the Mössbauer probe have a sufficiently large effect on the hyperfine field generated at the probe, to yield distinguishable components in the Mössbauer spectrum attributed to different configurations of the probe neighbours.…”