EFFECT OF DIFFERENT STRAIN ROUTES ON MECHANICAL PROPERTIES AND MICROSTRUCTURE OF COPPER

In the current paper, the role of change in strain routes was investigated, along with the cold rolling of copper metal. Four different strain routes including, (a) unidirectional rolling, (b) reverse rolling, (C) two-stage cross-rolling, and (d) multi-stage cross-rolling, were utilized to investigate the effect of strain routes change on microstructure, texture evolution, and anisotropy. Tensile strength in the unidirectional rolling sample compared to the cross-rolling sample decreased in the direction of initial rolling from 364 Mpa to 340 Mpa, in the direction of 45˚ to the initial rolling from 359 Mpa to 347 Mpa, and in the direction of perpendicular to the initial rolling from 371 Mpa to 360 Mpa. Texture intensity also decreased from 1413 in the unidirectional rolling sample to 992 in the cross-rolled sample. The results demonstrated that by rolling in different routes, the cross-rolling has led to a more homogeneous microstructure, less anisotropy, and weaker texture.

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Effect of the Rolling Process on Microstructures and Mechanical Properties of the Extruded LA91 Alloy Sheet

Materials Science Forum ◽

10.4028/www.scientific.net/msf.686.90 ◽

2011 ◽

Vol 686 ◽

pp. 90-95 ◽

Cited By ~ 2

Author(s):

Bin Jiang ◽

Qing Shan Yang ◽

Liang Gao ◽

Fu Sheng Pan

Keyword(s):

Mechanical Properties ◽

Microstructure Evolution ◽

Hot Rolling ◽

Rolling Process ◽

Alloy Sheet ◽

Rolling Reduction ◽

Thermal Compression ◽

Cross Rolling ◽

The Cross ◽

Rolling Route

The microstructure evolution of the extruded Mg-9Li-1Al (LA91) during rolling was investigated taking account of effects of different routes including hot rolling, and cross rolling. The rolling parameters were suggested by thermal compression testing. As a result, the suggested rolling parameters were 250°C and 1.0s-1. Transverse hot rolling would bring a finer microstructure to the as-rolled LA91 sheet. With the enhancement of the rolling reduction during unidirectional hot rolling the α-Mg phase became granular or short rod-like from long strip-like. Transverse + longitudinal hot rolling would improve the microstructure and was a better cross rolling route by which the strength and the elongation of the cross rolled LA91 sheet reached 243MPa and 20% respectively. The over-aging existed in the cross rolled LA91 sheets.

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Effects of Cross-Rolling on Deformation Texture Evolution in Unalloyed Titanium

Materials Science Forum ◽

10.4028/www.scientific.net/msf.879.2014 ◽

2016 ◽

Vol 879 ◽

pp. 2014-2019

Author(s):

Osamu Umezawa ◽

Norimitsu Koga

Keyword(s):

Rolling Mill ◽

Transverse Direction ◽

Texture Evolution ◽

True Strain ◽

Rolling Direction ◽

Deformation Texture ◽

Fiber Texture ◽

Cross Rolling ◽

Flat Rolling ◽

The Cross

Unalloyed titanium was rolled with 20% reduction in each pass at 293 K using a cross rolling mill, where the upper and lower rolling axes were skewed each other at an angle of 0, 5 or 10 degree with parallel position. Multi-pass flat-rolling was carried out without any lubricants up to the true strain of 1, where two kinds of rolling directions such as tandem (uni-direction for all passes) and reverse (opposite direction in every passes) were adopted. The strain of specimens was increased proportionally as higher passes regardless of the rolling conditions. The transverse direction (TD) split deformation texture in titanium was generally developed under the cross angle of 0 degree. In the present strips of tandem, a main orientation was identified as (-12-18)[10-10]. In the case of tandem with the cross angle of 5 degree, a fiber texture was developed along (-12-18). That is the reason why a rotation in the rolling direction (RD) was overlapped. In the case of reverse with the cross angle of 5 degree, the main orientation was separated into [10-10] and [2-311] that were corresponded to TD and RD splits, respectively.

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Microstructure and Mechanical Properties of Commercial Purity HIPed and Crushed Aluminum

Materials Science Forum ◽

10.4028/www.scientific.net/msf.584-586.579 ◽

2008 ◽

Vol 584-586 ◽

pp. 579-584 ◽

Cited By ~ 2

Author(s):

Quang Hien Bui ◽

Guy F. Dirras ◽

A. Hocini ◽

Salah Ramtani ◽

Akrum Abdul-Latif ◽

...

Keyword(s):

Mechanical Properties ◽

Strain Rate ◽

Mechanical Response ◽

Texture Evolution ◽

Hot Isostatic Pressing ◽

Commercial Purity ◽

Homogeneous Microstructure ◽

Average Grain Size ◽

Average Size ◽

The Impact

Ultrafine-grained aluminum microstructures were processed from commercial purity powder by combining hot isostatic pressing (HIP) and dynamic severe plastic deformation (DSPD). After the first step, the bulk consolidated material showed a random texture and homogeneous microstructure of equiaxed grains with an average size of 2µm. The material was then subsequently impacted, using a falling weight at a strain rate of 300s-1. The resulting material showed a microstructure having an average grain size of about 500 nm with a strong gradient of fiber-like crystallographic texture parallel to the impact direction. The mechanical properties of the impacted material were subsequently characterized under compressive tests at room temperature at a strain rate of 10-4s-1. The effect of the change of the deformation path on the mechanical response parallel (DN) and perpendicular (DT) to the impact direction was also investigated. These results are here discussed in relation with microstructure and texture evolution.

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Enhancement of ductility in Mg–3Al–1Zn alloy with tilted basal texture by electropulsing

Journal of Materials Research ◽

10.1557/jmr.2009.0436 ◽

2009 ◽

Vol 24 (12) ◽

pp. 3674-3679 ◽

Cited By ~ 16

Author(s):

Lei Guan ◽

Guoyi Tang ◽

Paul K. Chu ◽

Yanbin Jiang

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Tensile Ductility ◽

Texture Evolution ◽

Boundary Motion ◽

Basal Texture ◽

Rolled Sample ◽

Cold Rolled ◽

Electropulsing Treatment ◽

Grain Boundary Motion

The microstructure and texture evolution in a cold-rolled AZ31 magnesium alloy during electropulsing treatment (EPT) are investigated and correlated with the mechanical properties. The microstructure is effectively refined, and a tilted basal texture develops gradually during EPT. The yield stress in the treated samples is lower than that in the cold-rolled sample, indicating that texture softening is dominant over strengthening because of grain refinement. The phenomenon is primarily the result of the tilted basal texture. EPT improves the tensile ductility of the EPT samples significantly, albeit slightly compromising the tensile strength. The mechanism of the microstructure evolution during electropulsing is discussed from the viewpoint of grain-boundary motion. Moreover, the ductility enhancement is discussed in terms of the deformation mechanism and texture of the Mg alloy.

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Microstructure, Texture Evolution, and Mechanical Properties of MDFed GWZ Alloy Containing LPSO Phases on the Condition of High and Low Temperature Cycle Deformation

Metals ◽

10.3390/met10010136 ◽

2020 ◽

Vol 10 (1) ◽

pp. 136 ◽

Cited By ~ 2

Author(s):

Dong ◽

Zhang ◽

Che ◽

Yu ◽

Meng ◽

...

Keyword(s):

Mechanical Properties ◽

Low Temperature ◽

Texture Evolution ◽

Annealing Treatment ◽

Tensile Yield Strength ◽

Temperature Cycle ◽

Basal Texture ◽

Homogeneous Microstructure ◽

Homogenization Treatment ◽

Average Grain Size

The current work systematically investigated the microstructure, texture evolution, and mechanical properties of MDFed Mg-13Gd-4Y-2Zn-0.5Zr (wt%) alloy (GWZ) on the condition of high and low temperature cycle deformation. The high and low temperature cycle deformation was proposed on the basis of the conventional multi-directional forging (MDF) at decreasing temperature and annealing treatment. As a new method, it was aimed to timely uniform the microstructure and strengthen magnesium (Mg) matrix during the deformation process. A low accumulative strain of 3 after 1 pass resulted in a bimodal microstructure with undynamic recrystallized (unDRXed) regions and dynamic recrystallized (DRXed) grains, while a high accumulative strain of 12 after 4 passes lead to a homogeneous microstructure with fine DRXed grains. According to the experimental results, it indicated that the average grain size of 63 μm after homogenization treatment at 520 was refined remarkably to 5.20 μm after 4 passes at 420 °C through high and low temperature cycle deformation. The area fraction of DRXed grains was increased to 98.4%, which can be regarded as achieving complete DRX after 4 passes. The grain refinement was mainly caused by particle stimulation nucleation (PSN) and mechanism. As the MDF passes and accumulative strain increased, the basal texture was weakened and transformed from a strong basal texture to a random distribution gradually. Compared with conventional MDF at decreasing temperature, the mechanical properties were enhanced effectively. After 4 passes, the ultimate tensile strength (UTS), tensile yield strength (TYS), and failure elongation (FE) were 405 MPa, 305 MPa, and 13.1%, respectively.

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Microstructure and Texture Evolution of Cross Rolled AZ31 Mg Sheet

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.41-42.435 ◽

2008 ◽

Vol 41-42 ◽

pp. 435-438 ◽

Cited By ~ 1

Author(s):

Dae Guen Kim ◽

Hyeon Taek Son ◽

Jae Seol Lee

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Large Strain ◽

Texture Evolution ◽

Mg Alloys ◽

Planar Anisotropy ◽

Rolled Sample ◽

The Press ◽

R Value ◽

Press Formability

The aims of this study are to investigate the microstructure evolution of AZ31 Mg alloys with normal rolling and cross rolling as the large strain hot rolling affects microstructure, texture and mechanical properties of AZ31 Mg alloys. In the microstructures of as-rolled both samples, twins are clearly apparent, small and recrystallized grains are visible along some grain boundary and twinned regions. The Lankford values of large strain cross rolled sample obviously demonstrate the higher average r-value and lower planar anisotropy value. The press formability of cross rolled Mg alloy might be improved due to control of texture and grain size by severe deformation.

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Mechanical Properties and Press Formability of Mg Alloy Processed by Cross-Roll Rolling

Materials Science Forum ◽

10.4028/www.scientific.net/msf.561-565.179 ◽

2007 ◽

Vol 561-565 ◽

pp. 179-182

Author(s):

Yasumasa Chino ◽

Kensuke Sassa ◽

Akira Kamiya ◽

Naobumi Saito ◽

Mamoru Mabuchi

Keyword(s):

Mechanical Properties ◽

Transverse Direction ◽

Mg Alloy ◽

Texture Intensity ◽

Stretch Formability ◽

Rolled Specimen ◽

Grain Distribution ◽

The Cross ◽

Roll Axis ◽

Press Formability

Cross-roll rolling with different rolling routes (unidirectional rolling and reverse rolling) was carried out on a commercial Mg alloy sheets. In the cross-roll rolling, the roll axis was tilted by 7.5 degrees against the transverse direction. As a result of the Erichsen tests at 433 – 493 K, the stretch formability of the reverse cross-rolled specimen was higher than that of the unidirectional cross-rolled specimen. The reverse cross-rolled specimen showed lower average Lankford value compared with the unidirectional cross-rolled specimen. This is likely to be responsible for the enhanced stretch formability of the reverse cross-rolled specimen. The higher stretch formability was attributed to reduction of (0002) texture intensity, which was originated from random grain distribution.

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On the Influence of Cross-Rolling on Shear Band Formation and Texture Evolution in Low Carbon Steel Sheets

Textures and Microstructures ◽

10.1155/tsm.24.225 ◽

1995 ◽

Vol 24 (4) ◽

pp. 225-237 ◽

Cited By ~ 34

Author(s):

M. Y. Huh ◽

O. Engler ◽

D. Raabe

Keyword(s):

Texture Evolution ◽

Shear Bands ◽

Rolling Direction ◽

Low Carbon Steel ◽

Carbon Steels ◽

Low Carbon ◽

Band Formation ◽

Cross Rolling ◽

Rolled Specimen ◽

The Cross

In order to understand the influence of the crystallographic texture and the dislocation structure on the deformation mechanism in low carbon steels, the development of the texture and the microstructure in cross-rolled specimens was investigated by employing X-ray texture measurements and TEM observations. The cross-rolled specimens were obtained by rotating the rolling direction by various angles up to 90° after 30% initial straight-rolling of the hot rolled band. Whereas only few shear bands were found in the straight-rolled specimen even after heavy deformation, in the cross-rolled specimen shear bands were often found at reductions in excess of 60%. This observation is discussed in terms of the rotation of the arrangement of dislocations and microbands during cross-rolling. The rolling textures observed in the various samples were interpreted by means of Taylor type deformation models.

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