Improvement in Drawability (r Value) of an Aluminum Alloy Subjected to Groove Pressing

2010 ◽  
Vol 638-642 ◽  
pp. 1911-1916
Author(s):  
Ganesh Niranjan ◽  
Chakkingal Uday
Keyword(s):  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Rolling Direction ◽  
Al Alloy ◽  
Drawing Ratio ◽  
X Ray Diffraction ◽  
Shear Texture ◽  
Planar Anisotropy ◽  
Normal Anisotropy ◽  
X Ray

There is increasing interest in using Al alloy sheets for auto body applications. However Al alloys exhibit poor drawability as indicated by low values of the normal anisotropy, rm. Techniques for improving the value of rm rely on developing a favourable shear texture in the sheet. In this study, Al alloy AA 6061 sheets of dimensions 225 mm x 200 mm and 1 mm thick were subjected to severe plastic deformation by repeated groove pressing using a set of grooved and flat dies alternatively. The orientation of the grooves with respect to the rolling direction was also varied. Microstructure characterization and mechanical property measurements were carried out. X- ray diffraction scans were carried out to measure the relative intensities of the (111) and (200) peaks. The r values was measured as per ASTM standard E 517 on strip specimens cut at 0°, 45° and 90° to the rolling direction and the normal anisotropy value (rm) and planar anisotropy value (Δr) values were determined. The limiting drawing ratio (LDR) was determined using the Swift cupping test techniques. It was observed that the rm values increased from 0.72 in the as received condition to a maximum of 0.94 and the LDR increased from 1.93 to 2.06 when the groove pressing was carried out with grooves at to 45° the rolling direction. The improvement in rm values can be correlated to the texture developing in the sheet as a result of severe plastic deformation.

Influence of Severe Plastic Deformation on Physicomechanical Properties of Ti-40 mas % Nb Alloy

2016 ◽  
Vol 685 ◽  
pp. 525-529
Author(s):  
Zhanna G. Kovalevskaya ◽  
Margarita A. Khimich ◽  
Andrey V. Belyakov ◽  
Ivan A. Shulepov
Keyword(s):  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Cold Working ◽  
Young Modulus ◽  
Physicomechanical Properties ◽  
X Ray Diffraction ◽  
Refined Grains ◽  
X Ray ◽  
Initial Alloy ◽  
Composition Structure

The changes of the phase composition, structure and physicomechanical properties of Ti‑40 mas % Nb after severe plastic deformation are investigated in this paper. By the methods of microstructural, X-ray diffraction analysis and scanning electron microscopy it is determined that phase and structural transformations occur simultaneously in the alloy after severe plastic deformation. The martensitic structure formed after tempering disappears. The inverse α'' → β transformation occurs. The structure consisting of oriented refined grains is formed. The alloy is hardened due to the cold working. The Young modulus is equal to 79 GPa and it is less than that of initial alloy and close to the value obtained after tempering. It is possible that Young modulus is reduced by additional annealing.

Texture Development in a Model Al-Li Alloy Subjected to Severe Plastic Deformation

2006 ◽  
Vol 114 ◽  
pp. 337-344 ◽  
Author(s):  
Bogusława Adamczyk-Cieślak ◽  
Jaroslaw Mizera ◽  
Krzysztof Jan Kurzydlowski
Keyword(s):  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Equal Channel Angular Extrusion ◽  
Orientation Distribution ◽  
X Ray Diffraction ◽  
Technological Parameters ◽  
Initial State ◽  
Texture Characteristic ◽  
X Ray ◽  
Ultrafine Grained

The texture of Al – 0.7 wt. % Li alloy processed by two different methods of severe plastic deformation (SPD) has been investigated by X-ray diffraction, and analyzed in terms of the orientation distribution function (ODF). It was found that severe plastic deformation by both Equal Channel Angular extrusion (ECAE) and Hydrostatic Extrusion (HE) resulted in an ultrafine grained structure in an Al – 0.7 wt. % Li alloy. The microstructure, grain shape and size, of materials produced by SPD strongly depend on the technological parameters and methods applied. The texture of the investigated alloy differed because of the different modes of deformation. In the initial state the alloy exhibited a very strong texture consisting of {111} fibre component. A similar fibrous texture characteristic was also found after HE whereas after the ECAE the initial texture was completely changed.

Influence of Groove Pressing Process on the Drawability (R Value) of Aluminium Alloy AA 5052 Sheets

2013 ◽  
Vol 765 ◽  
pp. 363-367
Author(s):  
Ekta Jain ◽  
Uday Chakkingal
Keyword(s):  
Aluminium Alloy ◽  
Rolling Direction ◽  
Strain Ratio ◽  
X Ray Diffraction ◽  
Shear Texture ◽  
Plastic Strain Ratio ◽  
X Ray ◽  
Steel Sheets ◽  
Pressing Process ◽  
Plastic Deformation Process

Aluminium alloy sheets have poor drawability compared to steel sheets as indicated by the values of the plastic strain ratio or the R value. Because of the textures developed during commercial annealing and cold rolling processes, the R value for aluminium alloys is typically less than 1. Since the R value is heavily influenced by the crystallographic texture in the sheet, processes that develop a favourable texture can be utilised to improve the R value. In this study, a severe plastic deformation process called groove pressing has been used to repeatedly deform sheet specimens of aluminium alloy AA 5052. The R values of groove pressed specimens were experimentally determined. X-ray diffraction scans of the groove pressed specimens were carried out to measure the relative intensities of (111) and (002) peaks in the pattern. The largest increase in the R value was for specimens cut at 90° to the rolling direction and groove pressed to four passes. XRD data indicate that the groove pressing process is capable of introducing a favourable shear texture.

Severe Plastic Deformation of a Bainitic Rail Steel

2008 ◽  
Vol 584-586 ◽  
pp. 655-660 ◽  
Author(s):  
Anton Hohenwarter ◽  
Richard Stock ◽  
Reinhard Pippan
Keyword(s):  
Plastic Deformation ◽  
High Pressure ◽  
Severe Plastic Deformation ◽  
Retained Austenite ◽  
High Pressures ◽  
Rail Steel ◽  
Fatigue Cracks ◽  
Shear Direction ◽  
X Ray Diffraction ◽  
X Ray

Severe Plastic Deformation (SPD) is known to be an effective method of producing nanocrystalline materials, for instance by HPT and ECAP. These techniques are also capable of reproducing microstructures which arise naturally when high pressure and friction is involved, for example in wheel-rail contact problems. The resulting deformation layers build the origin point for fatigue cracks. For that reason the knowledge of the mechanical properties of these deformation layers are of vital importance. In the framework of this study a baintic rail steel quality was deformed by High Pressure Torsion up to distinctive equivalent strains at a nominal pressure of 6 GPa up to a final equivalent strain of 16. Afterwards the evolution of the resulting microstructure was investigated by Scanning Electron Microscopy, by microhardness measurements and X-ray diffraction. The bainitic structure showed a strong alignment and fragmentation into the shear direction with increasing strain, which was accompanied by an increase in hardness as well. X-ray diffraction measurements showed that the amount of retained austenite decreases dramatically after small amounts of strain, which indicates that retained austenite cannot be stabilized by high pressures. Torque measurements during deformation showed after strong hardening at the beginning, a saturation behaviour for higher strains, whereas for instance pearlitic rail steel qualities show further hardening.

Microstructural Changes during Precision Machining of Thin Substrates

2010 ◽  
Vol 447-448 ◽  
pp. 76-80
Author(s):  
K. Saptaji ◽  
Subbiah Sathyan
Keyword(s):  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Crystallographic Orientation ◽  
High Ratio ◽  
Machining Process ◽  
Deformation Mechanisms ◽  
Precision Machining ◽  
Depth Of Cut ◽  
X Ray Diffraction ◽  
X Ray

This paper reports investigations in machining of thin substrates with thickness less than 100m. The machining process induces severe plastic deformation through the thickness of the machined thin workpiece due to the high ratio of the depth of cut to workpiece thickness. The diamond face turning is used to machine thin workpieces down to a thickness less than 100m. The microstructure of the machined sample is studied and x-ray diffraction used to observe the crystallographic orientation / texture. The microstructures of the thin machined workpieces are seen to become more random, denser, and finer with the shape of the grains less elongated as compare to the bulk and thick machined sample. The x-ray diffraction analyses indicate that machining of thin substrates changes the texture or orientation. Different deformation mechanisms may occur when machining thin workpiece especially at thicknesses below 100m.

scholarly journals Mesoscopic residual stresses of plastic origin in zirconium: interpretation of X-ray diffraction results

2004 ◽  
Vol 37 (6) ◽  
pp. 934-940 ◽  
Author(s):  
D. Gloaguen ◽  
M. François ◽  
R. Guillen
Keyword(s):  
Experimental Data ◽  
Plastic Deformation ◽  
Residual Stresses ◽  
Rolling Direction ◽  
Deformation Mode ◽  
Prismatic Slip ◽  
X Ray Diffraction ◽  
Active Deformation ◽  
X Ray ◽  
Self Consistent

Complementary methods have been used to analyse residual stresses in a heat-treated Zr702 sheet which had undergone uniaxial plastic deformation: X-ray diffraction and self-consistent models. The elastoplastic self-consistent model has been used to simulate the experiments and exhibits agreement with experimental data. X-ray diffraction analysis in the rolling direction shows opposite stress values for {10\bar{1}4} and {20\bar{2}2} planes, respectively. The measured strains were generated by an anisotropic plastic deformation. The comparison between ∊ϕψversussin2ψ and simulations confirms that prismatic slip is the main active deformation mode. Plastic incompatibility stress in X-ray measurements should be taken into account in order to make a correct interpretation of the experimental data.

scholarly journals The influence of plastic deformation and chemical environment on the resistively of al-alloy overhead lines

2005 ◽  
Vol 2 (1) ◽  
pp. 63-76
Author(s):  
D. Nowak-Woźny ◽  
W. Mielcarek ◽  
K. Prociów ◽  
L. Woźny ◽  
J.B. Gajewski
Keyword(s):  
Plastic Deformation ◽  
Room Temperature ◽  
Measurement Data ◽  
Liquid Nitrogen Temperature ◽  
Mechanical Relaxation ◽  
Al Alloy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Overhead Lines ◽  
Chemical Ageing

The electrical resistively and intensity of X-ray diffraction reflexes were determined for overhead line wires deformed plastically and immersed at different solutions. Immersing (chemical ageing) was performed by plastic deformation along the wire axis. During chemical ageing the samples were exposed to the action of the Cl-, SO4 2-, and SO3 2- ions. Resistively was measured at room temperature and at liquid nitrogen temperature. After the X-ray and resistively measurement data were compared, it was found that three processes could take place: the flow of ions through the boundary between a sample and environment; the mechanical relaxation of vacancies near a line of dislocations, and the ordering of microstructure. These effects can lead to the anisotropy of resistively.

Study the Effect of Plastic Deformation in 8006 Al-Alloys by Positron Lifetime Spectroscopy, Vickers Hardness and X-Ray Diffraction

2017 ◽  
Vol 373 ◽  
pp. 142-145 ◽  
Author(s):  
Emad A. Badawi ◽  
M.A. Abdel-Rahman ◽  
Mohammed Salah ◽  
Mohamed Abdel-Rahman
Keyword(s):  
Plastic Deformation ◽  
Vickers Hardness ◽  
Positron Lifetime ◽  
Positron Annihilation Spectroscopy ◽  
Al Alloys ◽  
Al Alloy ◽  
X Ray Diffraction ◽  
Degree Of Deformation ◽  
X Ray ◽  
Positron Lifetime Spectroscopy

Due to the great effect of defects on the properties of the material including strength, ductility, resistivity and opacity, there are many techniques that are used in defect detecting. Positron annihilation spectroscopy (PAS), Vickers hardness, and X-ray diffraction were used to study the influence of plastic deformation on the properties of 8006 Al-alloy in this work. An increase in the positron lifetime and Vickers hardness with a bit Broadening of XRD peaks was observed with increasing the degree of deformation reflecting a large dislocation density produced by plastic deformation.

The Influence of Severe Plastic Deformation on Structure and Mechanical Properties the Aluminium Alloy EN AW 6082

2014 ◽  
Vol 635 ◽  
pp. 18-21 ◽  
Author(s):  
Petra Lacková ◽  
Ondrej Milkovič ◽  
Marián Buršák ◽  
Tibor Kvačkaj
Keyword(s):  
Mechanical Properties ◽  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Aluminium Alloy ◽  
Structural Changes ◽  
The Other ◽  
Cold Extrusion ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ecap Process

The effect of severe plastic deformation by ECAP process on the microstructures and mechanical properties of the aluminium alloy EN AW 6082 produced by cold extrusion is investigated. In both states were evaluated the structural changes by light microscopy, the analysis particles in structures, by X-ray diffraction (XRD) in transmission mode by synchrotron radiation and mechanical properties. Severe plastic deformation leads to strengthening of investigated EN AW 6082 alloy but on the other hand the plasticity of ECAP-ed alloy decreases.

Sign in / Sign up

Export Citation Format

Share Document