Formation of Nanostructure during High-Pressure Torsion of Al-Zn, Al-Mg and Al-Zn-Mg Alloys

2005 ◽  
Vol 237-240 ◽  
pp. 739-744 ◽  
Author(s):  
A.A. Mazilkin ◽  
Olga A. Kogtenkova ◽  
Boris B. Straumal ◽  
Ruslan Valiev ◽  
B. Baretzky
Keyword(s):  
Solid Solution ◽  
High Pressure ◽  
Equilibrium State ◽  
Room Temperature ◽  
Supersaturated Solid Solution ◽  
High Pressure Torsion ◽  
Mg Alloys ◽  
Supersaturated Solid Solutions ◽  
Before And After ◽  
Second Phases

Structure and phase composition of binary Al–Zn, Al–Mg and ternary Al–Zn–Mg alloys were studied before and after high pressure torsion (HPT) with shear strain 300. The size of (Al) grains and crystals of reinforcing second phases decreases drastically after HPT reaching nanometer range. As a result of HPT, the Zn-rich (Al) supersaturated solid solution decomposes completely and reaches the equilibrium state corresponding to room temperature. The decomposition is less pronounced for Al–Mg and Al–Zn–Mg alloys. We conclude that the severe plastic deformation of supersaturated solid solutions can be considered as a balance between deformation-induced disordering and deformation-accelerated diffusion towards the equilibrium state.

Hardness of Nanostructured Al-Zn, Al-Mg and Al-Zn-Mg Alloys Obtained by High-Pressure Torsion

2006 ◽  
Vol 249 ◽  
pp. 155-160 ◽  
Author(s):  
A.A. Mazilkin ◽  
B. Baretzky ◽  
S. Enders ◽  
Olga A. Kogtenkova ◽  
Boris B. Straumal ◽  
...  
Keyword(s):  
Solid Solution ◽  
High Pressure ◽  
Room Temperature ◽  
High Pressure Torsion ◽  
Mg Alloys ◽  
Solid Solution Hardening ◽  
Second Phase ◽  
Cast State ◽  
Supersaturated Solid Solutions ◽  
Mg Content

Microstructure and hardness of ternary Al–Zn–Mg alloys were studied both in as cast state and after high pressure torsion (HPT) with 5 torsions (shear strain about 6). The size of (Al) grains and of reinforcing second phase precipitates decreases drastically after HPT reaching nanometer range. During HPT, the Zn- and Mg-rich supersaturated (Al) solid solution decomposes and reaches the equilibrium state corresponding to the room temperature. In the as cast state the hardness of the supersaturated solid solutions increases with increasing Zn and Mg content due to the solid-solution hardening. However, after HPT the work hardening and Hall-Petch hardening due to the decreasing grain size competes with softening due to the decomposition of a supersaturated solid solution. In the net effect, the severe plastic deformation results in softening of ternary Al–Zn– Mg alloys.

Formation of nanograined structure and decomposition of supersaturated solid solution during high pressure torsion of Al–Zn and Al–Mg alloys

2004 ◽  
Vol 52 (15) ◽  
pp. 4469-4478 ◽  
Author(s):  
B.B Straumal ◽  
B Baretzky ◽  
A.A Mazilkin ◽  
F Phillipp ◽  
O.A Kogtenkova ◽  
...  
Keyword(s):  
Solid Solution ◽  
High Pressure ◽  
Supersaturated Solid Solution ◽  
High Pressure Torsion ◽  
Mg Alloys ◽  
Al Mg Alloys

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

2016 ◽  
Vol 879 ◽  
pp. 773-778 ◽  
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.

scholarly journals The Enrichment of (Cu, Sn) Solid Solution Driven by High-Pressure Torsion

Crystals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 766
Author(s):  
Boris Straumal ◽  
Askar Kilmametov ◽  
Anna Korneva ◽  
Pawel Zięba ◽  
Yuri Zavorotnev ◽  
...  
Keyword(s):  
Solid Solution ◽  
High Pressure ◽  
Theoretical Analysis ◽  
Annealing Temperature ◽  
High Pressure Torsion

Cu–14 wt% Sn alloy was annealed at temperatures of 320 and 500 °C. The concentration of tin cinit in the copper-based matrix increased with annealing temperature. The annealed samples were subjected to high-pressure torsion (HPT) at 6 GPa, 5 turns, 1 rpa. HPT led to the refinement of Cu grains. The shape of the colonies of α + ε phases changed only slightly. The HPT-driven enrichment of the Cu-based solid solution with Sn atoms cHPT–cinit decreased with increasing cinit. The performed theoretical analysis explained this behavior of the HPT-driven enrichment.

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

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.

The enrichment of solid solution in a two-phase alloy during the high pressure torsion

2021 ◽  
pp. 130386
Author(s):  
Anna Korneva ◽  
Askar Kilmametov ◽  
Yuri Zavorotnev ◽  
Leonid Metlov ◽  
Olga Popova ◽  
...  
Keyword(s):  
Solid Solution ◽  
High Pressure ◽  
High Pressure Torsion ◽  
Two Phase

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

2014 ◽  
Vol 619 ◽  
pp. 95-106 ◽  
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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