Microstructural Evolution during Recrystallization of Magnesiun Alloys

Microstructural evolution during the annealing of cold rolled Mg, Mg-1.5Nd and Mg-3Y sheets has been examined. The experimental results show a significant difference in recrystallization kinetics and grain growth between pure Mg and Mg-RE alloy sheets. Pure Mg sheet shows rapid recrystallization and grain growth, whereas recrystallization is considerably retarded in the Mg-RE alloys. Although recrystallized grains which are triggered at shear bands in the cold rolled pure Mg sheet show a relatively weak texture with a basal pole split into the sheet rolling direction, rapid grain growth is accompanied by re-strengthening of the basal-type texture. In contrast, a weak texture appears in the early recrystallization stage in Mg-RE alloys and is retained during annealing due to retarded recrystallization and grain growth.

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Influence of Rare Earth Addition on Texture Development during Static Recrystallization and Mechanical Behaviour of Magnesium Alloy Sheets

Materials Science Forum ◽

10.4028/www.scientific.net/msf.702-703.651 ◽

2011 ◽

Vol 702-703 ◽

pp. 651-654

Author(s):

Sang Bong Yi ◽

Lilian Rayas ◽

Stefanie Sandlöbes ◽

Stefan Zaefferer ◽

Dietmar Letzig ◽

...

Keyword(s):

Rare Earth ◽

Grain Growth ◽

Static Recrystallization ◽

Shear Bands ◽

Rare Earth Addition ◽

Axial Tensile ◽

Sheet Formability ◽

Cold Rolled ◽

Basal Type

The role of rare earth addition on the microstructure and texture during recrystallization of cold rolled sheets is investigated by a comparative study of pure Mg, Mg-3Y and Mg1.5Nd sheets. In pure Mg, nucleation occurs mainly at shear bands which results in a texture weakening. The basal-type texture re-strengthens rapidly during grain growth of the pure Mg sheet. In contrast, in the Mg-RE alloys the weaker texture formed during early recrystallization strage is retained during further annealing due to retarded grain growth. Uni-axial tensile and Erichsen tests show that ductility and sheet formability are significantly improved by addition of rare earth elements.

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Study on the Microstructure and Texture of Warm Rolled ZK60 Magnesium Alloy Sheet

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.557-559.1344 ◽

2012 ◽

Vol 557-559 ◽

pp. 1344-1348

Author(s):

Hong Mei Chen ◽

Hua Shun Yu ◽

Guang Hui Min ◽

Yun Xue Jin

Keyword(s):

Shear Bands ◽

Rolling Direction ◽

Rolling Process ◽

Warm Rolling ◽

Alloy Sheet ◽

Rolling Temperature ◽

Rolling Reduction ◽

Basal Pole ◽

Zk60 Alloy ◽

Twin Roll

The microstructure and macrotexture of ZK60 alloy sheet were investigated through OM and XRD, which were produced by twin roll casting and sequential warm rolling. Microstructure of twin roll cast ZK60 alloy changed from dendrite structure to fibrous structure with elongated grains and high density shear bands along the rolling direction after warm rolling process at different rolling parameters. The density of shear bands increased with the decreasing of the rolling temperature, or the increasing of per pass rolling reduction. Dynamic recrystallization could be found during the warm rolling process at and above 350oC, and many fine grains could be found in the shear band area. The warm rolled ZK60 alloy sheet exhibited strong (0001) basal pole texture. The formation of the shear bands tends to cause the basal pole tilt slightly to the transverse direction after warm rolling. The intensity of (0001) pole figure increased with the decreasing of rolling temperature, or the increasing of per pass rolling reduction.

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Modification of Microstructure and Texture in Highly Non-Flammable Mg-Al-Zn-Y-Ca Alloy Sheets by Controlled Thermomechanical Processes

Metals ◽

10.3390/met9020181 ◽

2019 ◽

Vol 9 (2) ◽

pp. 181 ◽

Cited By ~ 3

Author(s):

Sangbong Yi ◽

José Victoria-Hernández ◽

Young Kim ◽

Dietmar Letzig ◽

Bong You

Keyword(s):

Mechanical Properties ◽

Transverse Direction ◽

Texture Evolution ◽

Rolling Direction ◽

Reduction Degree ◽

Rolling Schedule ◽

Texture Type ◽

Basal Pole ◽

Thermomechanical Processes ◽

Basal Type

The influence of rolling temperature and pass reduction degree on microstructure and texture evolution was investigated using an AZXW3100 alloy, Mg-3Al-1Zn-0.5Ca-0.5Y, in wt.%. The change in the rolling schedule had a significant influence on the resulting texture and microstructure from the rolling and subsequent annealing. A relatively strong basal-type texture with a basal pole split into the rolling direction was formed by rolling at 450 °C with a decreasing scheme of the pass reduction degrees with a rolling step, while the tilted basal poles in the transverse direction were developed by using an increasing scheme of the pass reduction degrees. Rolling at 500 °C results in a further distinct texture type with a far more largely tilted basal pole into the rolling direction. The directional anisotropy of the mechanical properties in the annealed sheets was caused by the texture and microstructural features, which were in turn influenced by the rolling condition. The Erichsen index of the sheets varied in accordance to the texture sharpness, i.e., the weaker the texture the higher the formability. The sheet with a tetrarchy distribution of the basal poles into the transverse and rolling directions shows an excellent formability with an average Erichsen index of 8.1.

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Microstructural Evolution and Mechanical Properties of Pure Magnesium during Multi-Axial Compression

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.713-715.2759 ◽

2015 ◽

Vol 713-715 ◽

pp. 2759-2764 ◽

Cited By ~ 1

Author(s):

Xiao Hui Yang ◽

Song Ni ◽

Min Song

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Grain Growth ◽

Axial Compression ◽

Microstructural Evolution ◽

Pure Magnesium ◽

Compression Tests ◽

Axial Deformation ◽

Lower Strain ◽

Significant Difference

The effects of multi-axial compression (MAC) on the microstructures and mechanical properties of pure magnesium were investigated. It has been shown that grain refinement and grain growth occurred simultaneously during the MAC process. After 5 MAC passes, the grain size is mainly distributed in the range of 5~25 μm. The hardness of the specimens increases with increasing the strain (MAC pass), with the increment at lower strain being more obvious than that at higher strain. Compression tests showed that the samples show significant difference in mechanical properties along different directions due to the texture development. With increasing the MAC pass, the texture has been weakened due to multi-axial deformation.

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Magnetically Controlled Recrystallization Texture in Titanium

Materials Science Forum ◽

10.4028/www.scientific.net/msf.467-470.483 ◽

2004 ◽

Vol 467-470 ◽

pp. 483-488 ◽

Cited By ~ 2

Author(s):

Dmitri A. Molodov ◽

A.D. Sheikh-Ali

Keyword(s):

Magnetic Field ◽

Magnetic Susceptibility ◽

Grain Growth ◽

Texture Component ◽

Driving Force ◽

Recrystallization Texture ◽

Rolling Direction ◽

Field Direction ◽

Titanium Sheet ◽

Cold Rolled

The annealing of cold rolled (82%) titanium sheet at 750°C in a magnetic field of 19.4 Tesla results in a distinct difference between texture peaks when the sample is tilted by +30° or -30° to the field direction around the rolling direction, i.e. c (<0001>)-axis of grains corresponding to one texture component is aligned normal to the field direction. This result is attributed to grain growth affected by an additional driving force arising in a magnetic field by the anisotropy of the magnetic susceptibility of titanium.

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3D microstructural evolution of primary recrystallization and grain growth in cold rolled single-phase aluminum alloys

Modelling and Simulation in Materials Science and Engineering ◽

10.1088/1361-651x/aaa146 ◽

2018 ◽

Vol 26 (3) ◽

pp. 035011 ◽

Cited By ~ 4

Author(s):

Khaled Adam ◽

Dana Zöllner ◽

David P Field

Keyword(s):

Aluminum Alloys ◽

Grain Growth ◽

Microstructural Evolution ◽

Single Phase ◽

Primary Recrystallization ◽

Cold Rolled

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Microstructural evolution and grain growth mechanism of pre-twinned magnesium alloy during annealing

Journal of Magnesium and Alloys ◽

10.1016/j.jma.2020.11.015 ◽

2020 ◽

Author(s):

Ye Jin Kim ◽

Jong Un Lee ◽

Young Min Kim ◽

Sung Hyuk Park

Keyword(s):

Magnesium Alloy ◽

Grain Growth ◽

Microstructural Evolution ◽

Growth Mechanism

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Coupled Thermomechanical Response Measurement of Deformation of Nickel-Based Superalloys Using Full-Field Digital Image Correlation and Infrared Thermography

Materials ◽

10.3390/ma14092163 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2163

Author(s):

Krzysztof Żaba ◽

Tomasz Trzepieciński ◽

Sandra Puchlerska ◽

Piotr Noga ◽

Maciej Balcerzak

Keyword(s):

Surface Temperature ◽

Strain Rate ◽

Rolling Direction ◽

Image Correlation ◽

Uniaxial Tensile ◽

Uniaxial Tensile Test ◽

Response Measurement ◽

Sheet Rolling ◽

Inconel Alloys ◽

The Relationship

The paper is devoted to highlighting the potential application of the quantitative imaging technique through results associated with work hardening, strain rate and heat generated during elastic and plastic deformation. The aim of the research presented in this article is to determine the relationship between deformation in the uniaxial tensile test of samples made of 1-mm-thick nickel-based superalloys and their change in temperature during deformation. The relationship between yield stress and the Taylor–Quinney coefficient and their change with the strain rate were determined. The research material was 1-mm-thick sheets of three grades of Inconel alloys: 625 HX and 718. The Aramis (GOM GmbH, a company of the ZEISS Group) measurement system and high-sensitivity infrared thermal imaging camera were used for the tests. The uniaxial tensile tests were carried out at three different strain rates. A clear tendency to increase the sample temperature with an increase in the strain rate was observed. This conclusion applies to all materials and directions of sample cutting investigated with respect to the sheet-rolling direction. An almost linear correlation was found between the percent strain and the value of the maximum surface temperature of the specimens. The method used is helpful in assessing the extent of homogeneity of the strain and the material effort during its deformation based on the measurement of the surface temperature.

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Microstructure and Texture Evolution in Nickel during Accumulative Roll Bonding

Materials Science Forum ◽

10.4028/www.scientific.net/msf.879.454 ◽

2016 ◽

Vol 879 ◽

pp. 454-458 ◽

Cited By ~ 2

Author(s):

Jia Qi Duan ◽

Md Zakaria Quadir ◽

Michael Ferry

Keyword(s):

Grain Boundaries ◽

Accumulative Roll Bonding ◽

Texture Evolution ◽

Shear Bands ◽

Rolling Direction ◽

Sample Surface ◽

Deformation Texture ◽

Roll Bonding ◽

Equiaxed Grains ◽

Electron Back Scattered Diffraction

Microstructure and texture evolution of commercially pure Ni processed by accumulative roll-bonding (ARB) up to eight cycles were studied using electron back scattered diffraction (EBSD). During ARB processing, the original coarse equiaxed grains were gradually transformed into refined lamellar grains along the rolling direction (RD). Shear bands started forming after three cycles. The fraction of low angle grain boundaries (LAGBs) increased after the first and second cycle because of orientation spreading within the original grains. However, their fraction decreased with the evolution of high angle grain boundaries (HAGBs) during subsequent deformations, until saturation was reached after six cycles. Overall, the typical deformation texture components (S, Copper and Brass) were enhanced up to six ARB cycles and then only Copper was further strengthened. At higher cycles a higher Copper concentration was found near sample surface than the interiors due to a high frictional shear of ARB processing.

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