Hardness Homogeneity in an AZ80 Magnesium Alloy Processed by High-Pressure Torsion

Materials Science Forum ◽

10.4028/www.scientific.net/msf.879.139 ◽

2016 ◽

Vol 879 ◽

pp. 139-144

Author(s):

Saad A. Alsubaie ◽

Yi Huang ◽

Terence G. Langdon

Keyword(s):

High Pressure ◽

Magnesium Alloy ◽

Room Temperature ◽

Vickers Microhardness ◽

High Pressure Torsion ◽

Disc Diameter ◽

Az80 Magnesium Alloy

Experiments were conducted on an AZ80 magnesium alloy by processing by high-pressure torsion (HPT) at room temperature (296 K) for up to 10 turns under an imposed pressure of 6.0 GPa. Measurements of the Vickers microhardness along diameters and through the disk thicknesses were recorded after HPT to evaluate the evolution towards homogeneity. The results show hardness increases up to a factor of approximately 2 and the deformation is more homogeneous along the disc diameter than through the thickness.

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Recovery or Non-Recovery in Al-0.1% Mg and Al-1% Mg Alloy during High-Pressure Torsion Processing

Materials Science Forum ◽

10.4028/www.scientific.net/msf.879.773 ◽

2016 ◽

Vol 879 ◽

pp. 773-778 ◽

Cited By ~ 1

Author(s):

Yi Huang ◽

Justine Millet ◽

Nian Xian Zhang ◽

Pedro Henrique R. Pereira ◽

Terence G. Langdon

Keyword(s):

High Pressure ◽

Room Temperature ◽

High Pressure Torsion ◽

Mg Alloys ◽

Rapid Recovery ◽

Mg Alloy ◽

Disc Diameter ◽

Disc Centre ◽

Evolution Behavior ◽

Hardness Values

The Al-1% Mg and Al-0.1% Mg alloys were both processed by high-pressure torsion (HPT) at room temperature. In the Al-1% Mg alloy, the hardness values in the disc centre area are lower than in the disc edge area after 1/2 and 1 turn, and the area of lower hardness values in the disc centre decreases as the number of turns increases from 1/2 to 1 turn. Finally, the hardness values are reasonably homogenous along the disc diameter as the number of turns increases to 5 and 10 turns. The Al-0.1% Mg alloy displays a different hardness evolution behavior: the hardness values in the disc centre are higher than at the disc edge 1/2 and 1 turn, and the area of higher hardness values decreases as the numbers of turn increases from 1/2 to 1 turn. The hardness values evolve towards homogeneity along the disc diameter after 5 and 10 turns. EBSD microstructure investigations in the Al-0.1% Mg alloy reveal that a few low-angle boundaries exist at the disc edge after 1/2 turn. It is suggested that the higher hardness values in the disc centre in the Al-0.1% Mg alloy are related to rapid recovery at the disc edge where the material is subjected to heavy straining.

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Microstructure Evolution during High Pressure Torsion of AZ80 Magnesium Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.584-586.300 ◽

2008 ◽

Vol 584-586 ◽

pp. 300-305 ◽

Cited By ~ 6

Author(s):

Dogan Arpacay ◽

Sang Bong Yi ◽

Miloš Janeček ◽

Adem Bakkaloglu ◽

Lothar Wagner

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

High Pressure ◽

Magnesium Alloy ◽

Grain Refinement ◽

Microstructure Evolution ◽

Significant Variation ◽

High Pressure Torsion ◽

Grain Structure ◽

Az80 Magnesium Alloy

The microstructure evolution during high pressure torsion and its influence on the mechanical properties of AZ80 magnesium alloy is presented in this study. Significant grain refinement was observed after high pressure torsion, while the homogeneity of the grain structure increases with the number of revolutions. Grain size decreases to about 50 nm after 15 revolutions. The microhardness profiles measured at through-thickness and through-width directions show no significant variation at different positions of the sample. Moreover, the negligible effect of the revolution number on the microhardness value was observed.

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Evolution of microstructure and hardness in an AZ80 magnesium alloy processed by high-pressure torsion

Journal of Materials Research and Technology ◽

10.1016/j.jmrt.2015.11.006 ◽

2016 ◽

Vol 5 (2) ◽

pp. 152-158 ◽

Cited By ~ 19

Author(s):

Saad A. Alsubaie ◽

Piotr Bazarnik ◽

Malgorzata Lewandowska ◽

Yi Huang ◽

Terence G. Langdon

Keyword(s):

High Pressure ◽

Magnesium Alloy ◽

High Pressure Torsion ◽

Az80 Magnesium Alloy ◽

Evolution Of Microstructure

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GRAIN REFINEMENT AND MICROSTRUCTURE EVOLUTION IN ALUMINUM A2618 ALLOY BY HIGH-PRESSURE TORSION

Jurnal Teknologi ◽

10.11113/jt.v78.9163 ◽

2016 ◽

Vol 78 (6-9) ◽

Author(s):

Intan Fadhlina Mohamed ◽

Seungwon Lee ◽

Kaveh Edalati ◽

Zenji Horita ◽

Shahrum Abdullah ◽

...

Keyword(s):

Plastic Deformation ◽

High Pressure ◽

Grain Refinement ◽

Room Temperature ◽

Rotation Speed ◽

High Pressure Torsion ◽

Applied Pressure ◽

Saturation Level ◽

Microstructural Refinement ◽

Average Grain Size

This work presents a study related to the grain refinement of an aluminum A2618 alloy achieved by High-Pressure Torsion (HPT) known as a process of Severe Plastic Deformation (SPD). The HPT is conducted on disks of the alloy under an applied pressure of 6 GPa for 1 and 5 turns with a rotation speed of 1 rpm at room temperature. The HPT processing leads to microstructural refinement with an average grain size of ~250 nm at a saturation level after 5 turns. Gradual increases in hardness are observed from the beginning of straining up to a saturation level. This study thus suggests that hardening due to grain refinement is attained by the HPT processing of the A2618 alloy at room temperature.

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Hardening mechanism of commercially pure Mg processed by high pressure torsion at room temperature

Materials Science and Engineering A ◽

10.1016/j.msea.2014.09.068 ◽

2014 ◽

Vol 619 ◽

pp. 95-106 ◽

Cited By ~ 43

Author(s):

Xiao Guang Qiao ◽

Ya Wei Zhao ◽

Wei Min Gan ◽

Ying Chen ◽

Ming Yi Zheng ◽

...

Keyword(s):

High Pressure ◽

Room Temperature ◽

High Pressure Torsion ◽

Hardening Mechanism ◽

Commercially Pure

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The significance of self-annealing at room temperature in high purity copper processed by high-pressure torsion

Materials Science and Engineering A ◽

10.1016/j.msea.2016.01.027 ◽

2016 ◽

Vol 656 ◽

pp. 55-66 ◽

Cited By ~ 38

Author(s):

Yi Huang ◽

Shima Sabbaghianrad ◽

Abdulla I. Almazrouee ◽

Khaled J. Al-Fadhalah ◽

Saleh N. Alhajeri ◽

...

Keyword(s):

High Pressure ◽

High Purity ◽

Room Temperature ◽

High Pressure Torsion ◽

Purity Copper

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Intragranular deformation mechanisms in calcite deformed by high-pressure torsion at room temperature

Mineralogy and Petrology ◽

10.1007/s00710-019-00690-y ◽

2020 ◽

Vol 114 (2) ◽

pp. 105-118

Author(s):

Roman Schuster ◽

Gerlinde Habler ◽

Erhard Schafler ◽

Rainer Abart

Keyword(s):

High Pressure ◽

Twin Boundary ◽

Brittle Failure ◽

Room Temperature ◽

High Pressure Torsion ◽

Confining Pressure ◽

Temperature Deformation ◽

Orientation Relationships ◽

High Confining Pressure ◽

Confining Pressures

AbstractPolycrystalline calcite was deformed to high strain at room-temperature and confining pressures of 1–4 GPa using high-pressure torsion. The high confining pressure suppresses brittle failure and allows for shear strains >100. The post-deformation microstructures show inter- and intragranular cataclastic deformation and a high density of mechanical e$$ \left\{01\overline{1}8\right\} $$011¯8 twins and deformation lamellae in highly strained porphyroclasts. The morphologies of the twins resemble twin morphologies that are typically associated with substantially higher deformation temperatures. Porphyroclasts oriented unfavorably for twinning frequently exhibit two types of deformation lamellae with characteristic crystallographic orientation relationships associated with calcite twins. The misorientation of the first deformation lamella type with respect to the host corresponds to the combination of one r$$ \left\{10\overline{1}4\right\} $$101¯4 twin operation and one specific f$$ \left\{01\overline{1}2\right\} $$011¯2 or e$$ \left\{01\overline{1}8\right\} $$011¯8 twin operation. Boundary sections of this lamella type often split into two separated segments, where one segment corresponds to an incoherent r$$ \left\{10\overline{1}4\right\} $$101¯4 twin boundary and the other to an f$$ \left\{01\overline{1}2\right\} $$011¯2 or e$$ \left\{01\overline{1}8\right\} $$011¯8 twin boundary. The misorientation of the second type of deformation lamellae corresponds to the combination of specific r$$ \left\{10\overline{1}4\right\} $$101¯4 and f$$ \left\{01\overline{1}2\right\} $$011¯2 twin operations. The boundary segments of this lamella type may also split into the constituent twin boundaries. Our results show that brittle failure can effectively be suppressed during room-temperature deformation of calcite to high strains if confining pressures in the GPa range are applied. At these conditions, the combination of successive twin operations produces hitherto unknown deformation lamellae.

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