Destabilization and Induced Anomalous Work-hardening During the Plastic Deformation of Al-Cu Solid Solutions

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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Deformation Behaviour and Ultrafine Grained Structure Development in Steels with Different Carbon Content Subjected to Severe Plastic Deformation

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.345-346.45 ◽

2007 ◽

Vol 345-346 ◽

pp. 45-48 ◽

Cited By ~ 1

Author(s):

Jozef Zrník ◽

Sergey V. Dobatkin ◽

Ondrej Stejskal

Keyword(s):

Plastic Deformation ◽

Severe Plastic Deformation ◽

Work Hardening ◽

Favourable Effect ◽

Tensile Behaviour ◽

Dislocation Network ◽

Strength Increase ◽

Subgrain Structure ◽

Low Carbon ◽

Channel Angle

The article focuses on the results from recent experimental of severe plastic deformation of low carbon (LC) steel and medium carbon (MC) steel performed at increased temperatures. The grain refinement of ferrite respectively ferrite-pearlite structure is described. While LC steel was deformed by ECAP die (ε = 3) with a channel angle φ = 90° the ECAP severe deformation of MC steel was conducted with die channel angle of 120° (ε = 2.6 - 4). The high straining in LC steel resulted in extensively elongated ferrite grains with dense dislocation network and randomly recovered and polygonized structure was observed. The small period of work hardening appeared at tensile deformation. On the other side, the warm ECAP deformation of MC steel in dependence of increased effective strain resulted in more progressive recovery process. In interior of the elongated ferrite grains the subgrain structure prevails with dislocation network. As straining increases the dynamic polygonization and recrystallization became active to form mixture of polygonized subgrain and submicrocrystalline structure. The straining and moderate ECAP temperature caused the cementite lamellae fragmentation and spheroidzation as number of passes increased. The tensile behaviour of the both steels was characterized by strength increase however the absence of strain hardening was found at low carbon steel. The favourable effect of ferrite-pearlite structure modification due straining was reason for extended work hardening period observed at MC steel.

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Microstructural Change of Beta Type Titanium Alloy by Intense Plastic Deformation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.503-504.705 ◽

2006 ◽

Vol 503-504 ◽

pp. 705-710 ◽

Cited By ~ 1

Author(s):

Goroh Itoh ◽

Hisashi Hasegawa ◽

Tsing Zhou ◽

Yoshinobu Motohashi ◽

Mitsuo Niinomi

Keyword(s):

Plastic Deformation ◽

Work Hardening ◽

Static Recrystallization ◽

True Strain ◽

Microstructural Change ◽

Intense Plastic Deformation ◽

Rolled Plate ◽

Al Alloy ◽

Hot Rolled ◽

Zr Alloy

Usual static recrystallization treatment and a method to provide intense plastic deformation, ARB namely Accumulative Roll-Bonding, have been applied to two beta type titanium alloys, i.e. Ti-29Nb-13Ta-4.6Zr and Ti-15V-3Cr-3Sn-3Al. Microstructural change as well as work-hardening behavior was examined as a function of plastic strain. Both the work-hardening rate and the hardness at the initial as-hot-rolled state were smaller in the Ti-Nb-Ta-Zr alloy than in the Ti-V-Cr-Sn-Al alloy. Recrystallized grains of 14μm in size were obtained by the usual static recrystallization treatment, which was significantly smaller than that of the starting as-hot-rolled plate of 38μm. No significant change other than flattening and elongating of the original grains was found in the optical microscopic scale. It was revealed, however, from a TEM observation combined with selected area diffraction technique that geometric dynamic recrystallization occurred in the Ti-Nb-Ta-Zr alloy deformed at room temperature by a true strain of 5, resulting in an ultra-fine-grained microstructure where the grain size was roughly estimated to be about 100nm.

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Kinetics of the formation of supersaturated solid solutions upon mechanical alloying: I. General scheme of interaction of diffusion fluxes upon plastic deformation of multiphase nanomaterials

The Physics of Metals and Metallography ◽

10.1134/s0031918x12080133 ◽

2012 ◽

Vol 113 (8) ◽

pp. 733-741 ◽

Cited By ~ 1

Author(s):

L. S. Vasil’ev

Keyword(s):

Plastic Deformation ◽

Mechanical Alloying ◽

Solid Solutions ◽

General Scheme ◽

Supersaturated Solid Solutions ◽

Kinetics Of

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Studying Deformation Behaviors in Austenitic Stainless Steels within a Temperature Range of 143 K < T < 420 K

PNRPU Mechanics Bulletin ◽

10.15593/perm.mech/2021.1.03 ◽

2021 ◽

pp. 22-30

Author(s):

S. A Barannikova ◽

A. M Nikonova ◽

S. V Kolosov

Keyword(s):

Plastic Deformation ◽

Plastic Strain ◽

Strain Localization ◽

Work Hardening ◽

Deformation Localization ◽

Linear Hardening ◽

Jerky Flow ◽

Temperature Range ◽

Α Phase ◽

Flow Stage

This work deals with studying staging and macroscopic strain localization in austenitic stainless steel 12Kh18N9T within a temperature range of 143 K < T < 420 K. The visualization and evolution of macroscopic localized plastic deformation bands at different stages of work hardening were carried out by the method of the double-exposure speckle photography (DESP), which allows registering displacement fields with a high accuracy by tracing changes on the surface of the material under study and then comparing the specklograms recorded during uniaxial tension. The shape of the tensile curves σ(ε) undergoes a significant change with a decreasing temperature due to the γ-α'-phase transformation induced by plastic deformation. The processing of the deformation curves of the steel samples made it possible to distinguish the following stages of strain hardening, i.e. the stage of linear hardening and jerky flow stage. A comparative analysis of the design diagrams (with the introduction of additional parameters of the Ludwigson equation) and experimental diagrams of tension of steel 12Kh18N9T for different temperatures is carried out. The analysis of local strains distributions showed that at the stage of linear work hardening, a mobile system of plastic strain localization centers is observed. The temperature dependence of the parameters of plastic deformation localization at the stages of linear work hardening has been established. Unlike the linear hardening, the jerky flow possesses the propagation of single plastic strain fronts that occur one after another through the sample due to the γ-α' phase transition and the Portevin-Le Chatelier effect. It was found that at the jerky flow stage, which is the final stage before the destruction of the sample, the centers of deformation localization do not merge, leading to the neck formation.

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Properties of Nanoscaled Multiphase Structures and Non-Equilibrium Solid Solutions Obtained by Severe Plastic Deformation [Abstract + Supplemental Data]

MRS Proceedings ◽

10.1557/proc-977-0977-ff01-04 ◽

2006 ◽

Vol 977 ◽

Author(s):

Xavier Sauvage ◽

Xavier Quelennec ◽

Peter Jessner ◽

Florian Wetscher ◽

Reinhard Pippan

Keyword(s):

Mechanical Properties ◽

Plastic Deformation ◽

Grain Size ◽

Severe Plastic Deformation ◽

Solid Solutions ◽

Atom Probe ◽

Size Reduction ◽

Pure Metals ◽

Pure Cu ◽

Non Equilibrium

AbstractGrain size reduction induced by severe plastic deformation (SPD) and the resulting mechanical properties have been widely investigated for pure metals but less is known and reported about multi-phase materials. To study the grain size reduction mechanisms in multiphase structure subjected to SPD, two copper based composites (Cu-10%Fe and Cu-43%Cr) were severely deformed by torsion under high pressure. The grain size achieved with these composite materials is much smaller than in pure metals. It is for example in a range of 10 to 20 nm for the Cu-43%Cr composite, e.g. one order of magnitude lower than in pure Cu processed by SPD. Three dimensional atom probe data show also the formation of non equilibrium supersaturated solid solutions. The mechanisms of the deformation induced intermixing are discussed together with its influence on the mechanical properties.

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Some Properties of a Mechanical Model of Plasticity

Journal of Applied Mechanics ◽

10.1115/1.4009838 ◽

1948 ◽

Vol 15 (3) ◽

pp. 222-225

Author(s):

H. F. Bohnenblust ◽

Pol Duwez

Keyword(s):

Plastic Deformation ◽

Potential Energy ◽

Work Hardening ◽

Mechanical Model ◽

Strain Curve ◽

Hysteresis Curve ◽

Plastic Range ◽

Stress Strain Curve ◽

Stress Strain ◽

Mechanical Models

Abstract Various mechanical models explaining the plastic deformation of metals have been proposed. One of the present authors has shown that in some cases an analytical expression for the stress-strain curve and the hysteresis curve of a metal in the plastic range can be deduced from such a model. The present investigation is a further analysis of the model leading to the computation of the change in potential energy of the metal due to work-hardening.

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