Texture Heterogeneity in ECAP Deformed Copper

Polycrystalline copper of 4N purity has been deformed by equal channel angular pressing at room temperature using route BC. Local textures have been measured by high-energy synchrotron radiation along 3 lines in the cross section from the top to the bottom of the billets. The texture heterogeneity observed in the cross section is presented for 2 passes and discussed with regard to friction-affected material flow.

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Texture Gradient in ECAP Copper Measured by Synchrotron Radiation

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.105.327 ◽

2005 ◽

Vol 105 ◽

pp. 327-332 ◽

Cited By ~ 13

Author(s):

Werner Skrotzki ◽

N. Scheerbaum ◽

C.G. Oertel ◽

Heinz Günter Brokmeier ◽

Satyam Suwas ◽

...

Keyword(s):

Synchrotron Radiation ◽

Equal Channel Angular Pressing ◽

Room Temperature ◽

Extrusion Direction ◽

Orientation Imaging Microscopy ◽

High Energy ◽

Texture Gradient ◽

Fcc Metals ◽

Orientation Imaging ◽

Angular Pressing

Copper of 4N purity was deformed at room temperature by equal channel angular pressing (ECAP) using three passes of route A. The local microstructure and texture were investigated by orientation imaging microscopy and high-energy synchrotron radiation, respectively. The microstructure consists of elongated grains which are inclined to the extrusion direction. The texture is characterized by typical shear components of fcc metals which deviate from their ideal positions. The inclination of the grain long axis and the texture components with respect to the extrusion direction depends on the distance from the top of the extruded bar and changes from pass to pass. Reasons for the texture gradient are discussed.

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Experimental and Numerical Investigation of the ECAP Processed Copper: Microstructural Evolution, Crystallographic Texture and Hardness Homogeneity

Metals ◽

10.3390/met11040607 ◽

2021 ◽

Vol 11 (4) ◽

pp. 607

Author(s):

A. I. Alateyah ◽

Mohamed M. Z. Ahmed ◽

Yasser Zedan ◽

H. Abd El-Hafez ◽

Majed O. Alawad ◽

...

Keyword(s):

Grain Size ◽

Equal Channel Angular Pressing ◽

Cross Section ◽

Room Temperature ◽

Pure Copper ◽

High Density ◽

Ecap Processing ◽

Heterogeneous Distribution ◽

Angular Pressing ◽

Average Grain Size

The current study presents a detailed investigation for the equal channel angular pressing of pure copper through two regimes. The first was equal channel angular pressing (ECAP) processing at room temperature and the second was ECAP processing at 200 °C for up to 4-passes of route Bc. The grain structure and texture was investigated using electron back scattering diffraction (EBSD) across the whole sample cross-section and also the hardness and the tensile properties. The microstructure obtained after 1-pass at room temperature revealed finer equiaxed grains of about 3.89 µm down to submicrons with a high density of twin compared to the starting material. Additionally, a notable increase in the low angle grain boundaries (LAGBs) density was observed. This microstructure was found to be homogenous through the sample cross section. Further straining up to 2-passes showed a significant reduction of the average grain size to 2.97 µm with observable heterogeneous distribution of grains size. On the other hand, increasing the strain up to 4-passes enhanced the homogeneity of grain size distribution. The texture after 4-passes resembled the simple shear texture with about 7 times random. Conducting the ECAP processing at 200 °C resulted in a severely deformed microstructure with the highest fraction of submicron grains and high density of substructures was also observed. ECAP processing through 4-passes at room temperature experienced a significant increase in both hardness and tensile strength up to 180% and 124%, respectively.

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Texture Gradient in ECAP Silver Measured by Synchrotron Radiation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.495-497.821 ◽

2005 ◽

Vol 495-497 ◽

pp. 821-826 ◽

Cited By ~ 13

Author(s):

Werner Skrotzki ◽

N. Scheerbaum ◽

C.G. Oertel ◽

Heinz Günter Brokmeier ◽

Satyam Suwas ◽

...

Keyword(s):

Synchrotron Radiation ◽

Neutron Diffraction ◽

Room Temperature ◽

Extrusion Direction ◽

High Energy ◽

Texture Gradient ◽

Fcc Metals ◽

Local Texture ◽

Angular Pressing ◽

Global And Local

Silver of 3N purity was deformed at room temperature by equal channel angular pressing (ECAP) using three passes of route A. The global and local texture were investigated by neutron diffraction and high-energy synchrotron radiation, respectively. The texture is characterized by typical simple shear components of fcc metals which differently deviate from their ideal positions. Local texture measurements reveal that the intensity and inclination of the texture components with respect to the extrusion direction depend on the distance from the top of the extruded bar and change from pass to pass. Reasons for the texture gradient are discussed. The texture of silver is compared with that of copper having a higher stacking fault energy.

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Total cross sections of eγ → $$ eX\overline{X} $$ processes with X = μ, γ, e via multiloop methods

Journal of High Energy Physics ◽

10.1007/jhep01(2021)144 ◽

2021 ◽

Vol 2021 (1) ◽

Author(s):

Roman N. Lee ◽

Alexey A. Lyubyakin ◽

Vyacheslav A. Stotsky

Keyword(s):

Cross Section ◽

Cross Sections ◽

Elliptic Integral ◽

High Energy ◽

Calculation Methods ◽

Complete Elliptic Integral ◽

Total Cross Sections ◽

Multiloop Calculation ◽

The Cross ◽

Analytical Expressions

Abstract Using modern multiloop calculation methods, we derive the analytical expressions for the total cross sections of the processes e−γ →$$ {e}^{-}X\overline{X} $$ e − X X ¯ with X = μ, γ or e at arbitrary energies. For the first two processes our results are expressed via classical polylogarithms. The cross section of e−γ → e−e−e+ is represented as a one-fold integral of complete elliptic integral K and logarithms. Using our results, we calculate the threshold and high-energy asymptotics and compare them with available results.

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Effect of Equal-Channel Angular Pressing (ECAP) on Creep in Aluminium Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.539-543.2904 ◽

2007 ◽

Vol 539-543 ◽

pp. 2904-2909 ◽

Cited By ~ 15

Author(s):

Vàclav Sklenička ◽

Jiří Dvořák ◽

Marie Kvapilová ◽

Milan Svoboda ◽

Petr Král ◽

...

Keyword(s):

Equal Channel Angular Pressing ◽

Aluminium Alloys ◽

Creep Resistance ◽

Room Temperature ◽

Creep Behaviour ◽

Coarse Grained ◽

Pure Aluminium ◽

Creep Tests ◽

Angular Pressing ◽

Compression Creep

This paper examines the effect of equal-channel angular pressing (ECAP) on creep behaviour of pure aluminium, binary Al-0.2wt.%Sc alloy and ternary Al-3wt.%Mg-0.2wt.%Sc alloy. The ECAP was conducted at room temperature with a die that had a 90° angle between the channels and 8 repetitive ECAP passes followed route BC. Constant stress compression creep tests were performed at 473 K and stresses ranging between 16 to 80 MPa on ECAP materials and, for comparison purposes, on the initial coarse-grained materials. The results showed that the creep resistance of the ECAP processed Al-Sc and Al-Mg-Sc alloys was markedly deteriorated with respect to unpressed coarse-grained materials.

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Processing of Copper by Equal Channel Angular Pressing (ECAP) – Microstructure Investigations

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.641.286 ◽

2015 ◽

Vol 641 ◽

pp. 286-293

Author(s):

Beata Leszczyńska-Madej ◽

Maria W. Richert ◽

Agnieszka Hotloś ◽

Jacek Skiba

Keyword(s):

Equal Channel Angular Pressing ◽

Room Temperature ◽

Subgrain Size ◽

Pure Copper ◽

Shear Bands ◽

Angular Pressing ◽

Ecap Process ◽

Transmission Electron ◽

Different Types ◽

Diffraction Patterns

The present study attempts to apply Equal-Channel Angular Pressing (ECAP) to 99.99% pure copper. ECAP process was realized at room temperature for 4, 8 and 16 passes through route BC using a die having angle of 90°. The microstructure of the samples was investigated by means both light and transmission electron microscopy. Additionally the microhardness was measured and statistical analysis of the grains and subgrains was performed. Based on Kikuchi diffraction patterns misorientation was determined. There were some different types of bands in the microstructure after deformation. The shear bands, bands and in the submicron range the microshear bands and microbands are a characteristic feature of the microstructure of copper. Also characteristic was increasing of the number of bands with increasing of deformation and mutually crossing of the bands. The intersection of a bands and microbands leads to the formation of new grains with the large misorientation angle. The measured grain/subgrain size show, that the grain size is maintained at a similar level after each stage of deformation and is equal to d = 0.25 – 0.32 μm.

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Strength of Commercial Aluminum Alloys after Equal Channel Angular Pressing and Post-ECAP Processing

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.114.91 ◽

2006 ◽

Vol 114 ◽

pp. 91-96 ◽

Cited By ~ 10

Author(s):

Maxim Yu. Murashkin ◽

M.V. Markushev ◽

Julia Ivanisenko ◽

Ruslan Valiev

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Tensile Strength ◽

Aluminum Alloys ◽

Ultimate Tensile Strength ◽

Equal Channel Angular Pressing ◽

Room Temperature ◽

Solution Treatment ◽

Ecap Processing ◽

Angular Pressing

The effects of equal channel angular pressing (ECAP), further heat treatment and rolling on the structure and room temperature mechanical properties of the commercial aluminum alloys 6061 (Al-0.9Mg-0.7Si) and 1560 (Al-6.5Mg-0.6Mn) were investigated. It has been shown that the strength of the alloys after ECAP is higher than that achieved after conventional processing. Prior ECAP solution treatment and post-ECAP ageing can additionally increase the strength of the 6061 alloy. Under optimal ageing conditions a yield strength (YS) of 434 MPa and am ultimate tensile strength (UTS) of 470 MPa were obtained for the alloy. Additional cold rolling leads to a YS and UTS of 475 and 500 MPa with 8% elongation. It was found that the post-ECAP isothermal rolling of the 1560 alloy resulted in the formation of a nano-fibred structure and a tensile strength (YS = 540 MPa and UTS = 635 MPa) that has never previously been observed in commercial non-heat treatable alloys.

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TACHYON DYNAMICS OF THE BLACK DISC LIMIT IN THE HARD SMALL x PROCESSES IN QCD

Modern Physics Letters A ◽

10.1142/s021773230601975x ◽

2006 ◽

Vol 21 (07) ◽

pp. 549-558 ◽

Cited By ~ 3

Author(s):

B. BLOK ◽

L. FRANKFURT

Keyword(s):

Cross Section ◽

Impact Parameter ◽

High Energy ◽

Black Disk ◽

Black Disc ◽

Energy Behavior ◽

Small X ◽

The Cross ◽

The Impact ◽

Black Disc Limit

We investigate the effective field theory (EFT) which gives the approximate description of the scattering of two hard small dipoles in the small x processes in QCD near the black disc limit (BDL). We argue that the perturbative QCD approaches predict the existence of tachyon and visualize it in the approximation where α′P=0. We demonstrate that the high energy behavior of the cross-section depends strongly on the diffusion law in the impact parameter plane. On the other hand, almost threshold behavior of the cross section of the hard processes and multiplicities, i.e. fast increase of cross sections (color inflation), melting of ladders into color network and softening of the longitudinal distributions of hadrons are qualitatively insensitive to the value of diffusion in the impact parameter space. We evaluate α′P near the black disk limit and find significant α′P as the consequence of the probability conservation.

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Quasielastic Lepton Scattering off Two-Component Dark Matter in Hypercolor Model

Symmetry ◽

10.3390/sym12050708 ◽

2020 ◽

Vol 12 (5) ◽

pp. 708 ◽

Cited By ~ 1

Author(s):

Vitaly Beylin ◽

Maxim Bezuglov ◽

Vladimir Kuksa ◽

Egor Tretiakov

Keyword(s):

Dark Matter ◽

Total Cross Section ◽

Cross Section ◽

Strong Dependence ◽

Cosmic Ray ◽

High Energy ◽

Dominant Contribution ◽

Quasielastic Scattering ◽

Two Component ◽

The Cross

The interaction of high-energy leptons with components of Dark Matter in a hypercolor model is considered. The possibility of detection, using IceCube secondary neutrinos produced by quasielastic scattering of cosmic ray electrons off hidden mass particles, is investigated. The dominant contribution to the cross section results from diagrams with scalar exchanges. A strong dependence of the total cross section on the Dark Matter components mass is also found.

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