Anelastic deformation of high purity aluminum at room temperature

In this study, a purity of 99.995percent high purity aluminum was multi-directionally forged up to a maximum cumulative strain of 4.5 at room temperature. The macro and micro structure evolution in the multi-directionally forge process was investigated by structure observations and hardness measurements. The results show that the inhomogeneous deformation of multi-directional forging results in that the structure and hardness is quite different between the easy deformation zone and stagnant zone. Dynamic recrystallization occurs in easy deformation zone of high purity aluminum sample at room temperature as the cumulative true strain is 1.5 (3 forging passes), while the structure in the stagnant zone is still not recrystallizated even at a cumulative true strain of 4.5 (9 forging passes). The recrystallized grain size in the easy deformation zone is reduced with the number of forging passes, and the area of recrystallize grains increase with the number of forging passes.

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Effect of Multi-Forging Condition on Deformed Structure and Mechanical Properties of A 99.995 Percent High Purity Aluminum

Materials Science Forum ◽

10.4028/www.scientific.net/msf.817.360 ◽

2015 ◽

Vol 817 ◽

pp. 360-366 ◽

Cited By ~ 2

Author(s):

Qing Feng Zhu ◽

Wen Jing Wang ◽

Zhi Hao Zhao ◽

Yu Bo Zuo ◽

Jian Zhong Cui

Keyword(s):

Mechanical Properties ◽

Mechanical Property ◽

High Purity ◽

Deformation Zone ◽

Room Temperature ◽

Stagnant Zone ◽

Water Cooling ◽

High Purity Aluminum

A purity of 99.995% high purity aluminum was deformed by multi-forging with different conditions (forged by different forging passes with and without water cooling). The effect of multi-forging on macrostructure and mechanical property of the high purity aluminum was investigated. The results show that the deformation heat during the MDF process can obviously affect the recrystallization of the high purity aluminum. Recrystallization occurs in the easy deformation zone of the sample as forged by 3 passes at room temperature. While, when the sample are cooling by water for each pass, no recrystallization occurs in the whole sample as forged by 9 passes. When the high purity forged at room temperature, the structure difference between the easy deformation zone and stagnant zone can not be eliminated by increasing the forging pass to 9. While, the area of the recrystal grain extends with increment of the forging pass.

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Photopyroelectric Measurement of the Thermal Diffusivity of Recrystallized High Purity Aluminum

Research in Nondestructive Evaluation ◽

10.1080/09349849108968041 ◽

1991 ◽

Vol 3 (1) ◽

pp. 69-80

Author(s):

S. B. Peralta ◽

S. C. Ellis ◽

C. Christofides ◽

A. Mandeiis ◽

H. Sang ◽

...

Keyword(s):

Thermal Diffusivity ◽

High Purity ◽

High Purity Aluminum

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Room-temperature oxygen vacancy migration induced reversible phase transformation during the anelastic deformation in CuO

Nature Communications ◽

10.1038/s41467-021-24155-z ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Lei Li ◽

Guoxujia Chen ◽

He Zheng ◽

Weiwei Meng ◽

Shuangfeng Jia ◽

...

Keyword(s):

High Temperature ◽

Oxygen Vacancy ◽

Room Temperature ◽

High Temperature Superconductivity ◽

Experimental Investigations ◽

Solid State Chemistry ◽

Vacancy Migration ◽

Scientific Disciplines ◽

Anelastic Deformation ◽

Reversible Phase

AbstractFrom the mechanical perspectives, the influence of point defects is generally considered at high temperature, especially when the creep deformation dominates. Here, we show the stress-induced reversible oxygen vacancy migration in CuO nanowires at room temperature, causing the unanticipated anelastic deformation. The anelastic strain is associated with the nucleation of oxygen-deficient CuOx phase, which gradually transforms back to CuO after stress releasing, leading to the gradual recovery of the nanowire shape. Detailed analysis reveals an oxygen deficient metastable CuOx phase that has been overlooked in the literatures. Both theoretical and experimental investigations faithfully predict the oxygen vacancy diffusion pathways in CuO. Our finding facilitates a better understanding of the complicated mechanical behaviors in materials, which could also be relevant across multiple scientific disciplines, such as high-temperature superconductivity and solid-state chemistry in Cu-O compounds, etc.

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Preparation of High-Purity Ultrafine α-Al2O3 by Solid-State Reaction at Room Temperature

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.683 ◽

2008 ◽

Vol 368-372 ◽

pp. 683-685

Author(s):

Cheng Wei Hao ◽

Bo Lin Wu ◽

Ji Yan Li

Keyword(s):

Solid State ◽

High Purity ◽

Solid State Reaction ◽

Room Temperature ◽

Raw Materials ◽

Phase Particle ◽

Phase Transformation Temperature ◽

Particle Size And Morphology ◽

Size And Morphology ◽

Α Al2o3

Ammonium aluminium carbonate hydroxide (AACH), with a small quantity of γ-AlOOH, was synthesized through solid-state reaction at room temperature using AlCl3·6H2O and NH4HCO3 as raw materials and polyethylene glycol (PEG-10000) as the dispersant. After calcined at 1100°C for 1.5h, α-Al2O3 powders with primary particle sizes of 20~30nm were obtained. The crystal phase, particle size and morphology of the high-purity ultrafine α-Al2O3 were characterized. The results showed that a small quantity of γ-AlOOH in the AACH decomposed and formed crystal seeds. The presence of crystal seeds reduced the nucleation activation energy and therefore reduced the phase transformation temperature.

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