The Comparative Mössbauer Analysis of Superfine Structure of Hadfield Steel upon Different Kinds of Severe Deformation

2011 ◽  
Vol 319-320 ◽  
pp. 13-23 ◽  
Author(s):  
V.A. Shabashov ◽  
A.E. Zamatovsky ◽  
L.G. Korshunov ◽  
A.V. Litvinov
Keyword(s):  
Plastic Deformation ◽  
Short Range ◽  
Room Temperature ◽  
Precipitation Hardening ◽  
Effective Field ◽  
Hadfield Steel ◽  
Magnetic Characteristics ◽  
Short Range Ordering ◽  
Superfine Structure ◽  
Mössbauer Analysis

Severe plastic deformation (friction, compression shear, filing or rolling) of Hadfield steel leads to the growth of the internal effective field on 57Fe cores, removal of the magnetic degeneracy in spectra, and the extension of the paraprocess up to room temperature. The observed change of the magnetic characteristics is explained by the deformation-induced redistribution of carbon and short-range ordering of carbon and manganese. Since the magnetic degeneracy is removed in the Hadfield steel upon deformation, it is possible to consider a mechanism of magnetic precipitation hardening, which is realized in local magnetically ordered regions of the structure containing Mn-C pairs.

scholarly journals Mössbauer Analysis of Deformation–Induced Acceleration of Short-Range Concentration Separation in Fe-Cr Alloys—Effect of the Substitution Impurity: Sb and Au

Metals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 725
Author(s):  
Valery Shabashov ◽  
Kirill Kozlov ◽  
Yurii Ustyugov ◽  
Andrey Zamatovskii ◽  
Timofey Tolmachev ◽  
...  
Keyword(s):  
Plastic Deformation ◽  
Mössbauer Spectroscopy ◽  
Severe Plastic Deformation ◽  
Positron Annihilation ◽  
Temperature Region ◽  
Short Range ◽  
Mossbauer Spectroscopy ◽  
Short Range Ordering ◽  
Mössbauer Analysis ◽  
Effect Of Doping

The effect of doping the ferrite alloy Fe-16Cr by the oversized impurities Sb and Au on the mechanism of the short-range ordering induced by “warm” severe plastic deformation was studied using the method of Mössbauer spectroscopy. A comparison between the results obtained and the positron annihilation data on the evolution of the defects of vacancy type stabilized by the impurities Sb and Au was performed. It has been established that the impurities Sb and Au entail a shift of the temperature region of short-range ordering realization in conditions of applying pressure torsion towards greater temperatures by 250 and 100 K, respectively.

Room-temperature-deformation-induced chemical short-range ordering in a supersaturated ultrafine-grained Al-Zn alloy

2022 ◽  
Vol 210 ◽  
pp. 114423
Author(s):  
Z.Z. Song ◽  
R.M. Niu ◽  
X.Y. Cui ◽  
E.V. Bobruk ◽  
M. Murashkin ◽  
...  
Keyword(s):  
Short Range ◽  
Room Temperature ◽  
Temperature Deformation ◽  
Ultrafine Grained ◽  
Short Range Ordering ◽  
Zn Alloy

Relation between icosahedral short-range ordering and plastic deformation in Zr–Nb–Cu–Ni–Al bulk metallic glasses

2011 ◽  
Vol 59 (7) ◽  
pp. 2814-2822 ◽  
Author(s):  
Z.W. Zhu ◽  
L. Gu ◽  
G.Q. Xie ◽  
W. Zhang ◽  
A. Inoue ◽  
...  
Keyword(s):  
Plastic Deformation ◽  
Metallic Glasses ◽  
Short Range ◽  
Bulk Metallic Glasses ◽  
Short Range Ordering

Aging-induced double hysteresis loops in bismuth-doped (Ba,Ca)TiO3 ferroelectric ceramics

2009 ◽  
Vol 24 (10) ◽  
pp. 3073-3077 ◽  
Author(s):  
Sining Yun ◽  
Xiaoli Wang ◽  
Jing Shi ◽  
Delong Xu
Keyword(s):  
Solid State ◽  
Point Defects ◽  
Short Range ◽  
Room Temperature ◽  
Domain Switching ◽  
Hysteresis Loops ◽  
Ferroelectric Ceramics ◽  
Solid State Reaction Technique ◽  
Conventional Solid State Reaction ◽  
Short Range Ordering

Bismuth-doped (Ba1−xCax)TiO3 ceramics (x = 0.10, Bi-BCT) were prepared by a conventional solid-state reaction technique. An abnormal double-like hysteresis polarization–electric (P–E) loop was observed at room temperature for aged Bi-BCT. Raman scattering gives critical evidence for the formation of O2− vacancies in Bi-BCT. The change from the single P–E loops in the fresh samples to the double loops in the aged samples excludes the existence of a ferroelectric–antiferroelectric transition in Bi-BCT. A reversible domain switching mechanism resulting from a symmetry-conforming short-range ordering of point defects gives a reasonable explanation for the naturally age-induced double-like P–E loops in Bi-BCT.

Room-Temperature Short-Range Ordering in Fe-Si Alloys Observed by Internal Friction

2008 ◽  
Vol 137 ◽  
pp. 83-90
Author(s):  
Fernando González ◽  
Daniel Ruiz ◽  
Yvan Houbaert
Keyword(s):  
Internal Friction ◽  
Cold Rolling ◽  
Short Range ◽  
Room Temperature ◽  
Ageing Time ◽  
Low Carbon ◽  
New Production ◽  
Short Range Ordering ◽  
Si Content ◽  
Ageing Phenomenon

Research performed at Ghent University, regarding new production methods for electrical steel, has shown that high silicon steel suffers an ageing phenomenon at room temperature. Recent studies carried out by the same group using different analysis techniques (Mossbauer spectroscopy, neutron diffraction, etc) brought to light a probable process of ordering towards the D03-structure, which is responsible for the observed low ductility during cold rolling and makes the processing of steel extremely difficult. In addition, the Si-steels become more brittle as the delay time between hot and cold rolling is increased. Frequency dependent internal friction (FDIF) studies were performed on different Fe - Si alloys with a Si content varying from 3.73 at. % to 8.7 at. % immediately after several thermal treatments and compared with ultra-low carbon steel. The evolution of relaxation peaks during the IF measurements, performed at constant room temperature, helps to understand the ageing mechanisms. Three processes have been observed: firstly, as expected, addition of Si reduces the carbon Snoek peak. Secondly, a peak associated to C - Si is formed. Thirdly, a low frequency peak associated with Zener relaxation (Si atom pairs) appears for a content of approximately 3.77 wt. % Si. The two latter peaks decrease with ageing time and in the case of the Zener peak there is a notable displacement to higher frequencies with a small increase of the Si content. The reduction of the peaks during the ageing after annealing is more noticeable in quenched specimens than in air cooled ones, and in furnace cooled specimens the reduction is even smaller, indicating that the process is really an ageing phenomenon. Room temperature short-range ordering might explain both the lowering of the Zener peak and the observed macroscopic embrittlement.

Thermoelectroc Power for Phase Transformation Study in Metallic Alloys

1982 ◽  
Vol 21 ◽  
Author(s):  
R. Borrelly ◽  
P. Merle ◽  
J. Merlin ◽  
J.M. Pelletier ◽  
G. Vigier
Keyword(s):  
Plastic Deformation ◽  
Phase Transformation ◽  
Short Range ◽  
Metallic Alloys ◽  
Cu Alloys ◽  
Short Range Ordering ◽  
Power Measurements ◽  
Transformation Study ◽  
Microstructure Of The Material ◽  
Thermoelectrical Power

ABSTRACTRecent experiments have proved the efficiency of T.E.P. measurements in phase transformation studies. The main features of the technique are presented and two particular examples of application are given (influence of plastic deformation on short range ordering (S.R.O.) and study of dissolution of the equilibrium Θ phase in Al-Cu alloys).Since the first studies [1] only very few attempts have been made to use thermoelectrical power measurements (T.E.P.) to characterize the evolution of an alloy during phase transformation. However, in spite of the complexity of the theoretical interpretations, T.E.P. measurements can give valuable informations on the microstructure of the material, sometimes with more easiness or more precision than with other techniques or even informations which would be impossible to obtain by another way.

Mechanochemical Synthesis of ZrTiO4 Precursor from Inhomogeneous Mixed Gels

1994 ◽  
Vol 346 ◽  
Author(s):  
Tetsuhiko isobe ◽  
Yutaka Okamoto ◽  
Mamoru Senna
Keyword(s):  
Raman Spectroscopy ◽  
Mechanical Stress ◽  
Mechanochemical Synthesis ◽  
Short Range ◽  
Room Temperature ◽  
Hydroxyl Groups ◽  
Short Range Ordering ◽  
Two Phases ◽  
Mechanochemical Reactions ◽  
Metallic Species

ABSTRACTEffects of vibration ball-milling of a powdered mixture of two gels, prepared from mixing ZrO2 andTiO2 sols, on crystallization processes during heating are studied in order to elucidate enhanced mechanochemical reactions with the aid of hydroxyl groups. TiO2 (anatase) and ZrO2 (tetragonal) crystallized at 698 K and 712 K, respectively, when heating non-milled gel mixture at 10 K min1 in air. Few reactions between the two phases were detected below 1023 K. After vibro-milling a powdered gel mixture at room temperature for 3 to 30 h, ZrTiO4 (orthorhombic) crystallized directly from non-crystalline precursors on heating to 1023 K. The fraction of crystallizedZrTi04, determined by Raman spectroscopy, increased linearly with increasing the index of micro-homogeneity for non-heated gels. We suggest that short-range ordering of ZrTiO4 rather than crystallization of individual oxides occurs through the non-thermal atomic movement between different metallic species under mechanical stress.

Electron microscope studies of the plastic deformation of ternary alloys based on GaAs

1990 ◽  
Vol 48 (4) ◽  
pp. 1120-1120
Author(s):  
R. Haswell ◽  
U. Bangert ◽  
P. Charsley
Keyword(s):  
Plastic Deformation ◽  
Electron Microscope ◽  
Room Temperature ◽  
Stacking Faults ◽  
The Other ◽  
Ternary Alloys ◽  
Dislocation Mobility ◽  
Semiconducting Materials ◽  
Micro Indentation

A knowledge of the behaviour of dislocations in semiconducting materials is essential to the understanding of devices which use them . This work is concerned with dislocations in alloys related to the semiconductor GaAs . Previous work on GaAs has shown that microtwinning occurs on one of the <110> rosette arms after indentation in preference to the other . We have shown that the effect of replacing some of the Ga atoms by Al results in microtwinning in both of the rosette arms.In the work to be reported dislocations in specimens of different compositions of Gax Al(1-x) As and Gax In(1-x) As have been studied by using micro indentation on a (001) face at room temperature . A range of electron microscope techniques have been used to investigate the type of dislocations and stacking faults/microtwins in the rosette arms , which are parallel to the [110] and [10] , as a function of composition for both alloys . Under certain conditions microtwinning occurs in both directions . This will be discussed in terms of the dislocation mobility.

On effect of surface hardening on impact and abrasive wear resistance of Hadfi eld steel

2020 ◽  
pp. 252-255
Author(s):  
V.I. Bolobov ◽  
V.S. Bochkov ◽  
E.V. Akhmerov ◽  
V.A. Plashchinsky ◽  
E.A. Krivokrisenko E.A.
Keyword(s):  
Plastic Deformation ◽  
Wear Resistance ◽  
Abrasive Wear ◽  
Work Hardening ◽  
Surface Hardening ◽  
Cold Work ◽  
Abrasive Wear Resistance ◽  
Hadfield Steel ◽  
Mining Equipment ◽  
Effect Of Surface

On the example of Hadfield steel, as the most common material of fast-wearing parts of mining equipment, the effect of surface hardening by plastic deformation on their impact and abrasive wear resistance is considered. Wear test is conducted on magnetic ironstone as typical representative of abrasive and hard rock. As result of wear of initial samples with hardness of ∼200 HB and samples pre-hardened with different intensities to the hardness of 300, 337 and 368 HB, it is found that during the initial testing period, the initial samples pass the “self-cold-work hardening” stage with increase in hardness to ∼250 HB, which remains virtually unchanged during further tests; the hardness of the pre-hardened samples does not change significantly throughout the tests. It is established that the rate of impact-abrasive wear of pre-hardened samples is significantly (up to 1.4 times) lower than the original ones that are not subjected to plastic deformation, and decreases with increasing degree of cold-work hardening. Preliminary surface hardening by plastic deformation can serve as effective way to increase the service life of fast-wearing working parts of mining equipment.

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