Investigation of Effect of Preliminary Annealing on Superplasticity of Ultrafine-Grained Conductor Aluminum Alloys Al-0.5%Mg-Sc

Effect of preliminary precipitation of Al3Sc particles on the characteristics of superplastic conductor Al-0.5%Mg-X%Sc (X = 0.2, 0.3, 0.4, 0.5 wt.%) alloys with ultrafine-grained (UFG) microstructure has been studied. The precipitation of the Al3Sc particles took place during long-time annealing of the alloys at 300 °C. The preliminary annealing was shown to affect the superplasticity characteristics of the UFG Al-0.5%Mg-X%Sc alloys (the elongation to failure, yield stress, dynamic grain growth rate) weakly but to promote more intensive pore formation and to reduce the volume fraction of the recrystallized microstructure in the deformed and non-deformed parts of the aluminum alloy specimens. The dynamic grain growth was shown to go in the deformed specimen material nonuniformly–the maximum volume fraction of the recrystallized microstructure was observed in the regions of the localization of plastic deformation.

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Investigation of superplasticity and dynamic grain growth in ultrafine-grained Al-0.5%Mg-Sc alloys

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2021.160099 ◽

2021 ◽

pp. 160099

Author(s):

V.N. Chuvil'deev ◽

M.Yu. Gryaznov ◽

S.V. Shotin ◽

V.I. Kopylov ◽

A.V. Nokhrin ◽

...

Keyword(s):

Grain Growth ◽

Ultrafine Grained ◽

Dynamic Grain Growth

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Enhanced Strength and Ductility of AZ80 Magnesium Alloys by Spray Forming and ECAP Techniques

KnE Materials Science ◽

10.18502/kms.v1i1.580 ◽

2016 ◽

Vol 1 (1) ◽

pp. 168 ◽

Cited By ~ 1

Author(s):

L.L. Tang ◽

Y.H. Zhao ◽

R.K. Islamgaliev ◽

R.Z. Valiev

Keyword(s):

Volume Fraction ◽

Spray Forming ◽

Angular Pressing ◽

Forming Technology ◽

Ultrafine Grained ◽

Average Grain Size ◽

Elongation To Failure ◽

Mechanical Tensile ◽

Deformation Layer ◽

Strength And Ductility

Fast spray forming technology followed by equal channel angular pressing (ECAP) was employed to obtain a specific microstructure: separated coarse magnesium grains surrounded by deformation networks. The deformation layer consisted of ultrafine grained magnesium with an average grain size of 0.6 μm and ellipsoidal shaped β-Mg17Al12 particles with a size of 200-300 nm and a volume fraction of 13%. Mechanical tensile test demonstrates the advantage of the specific structure: a yield strength of 235MPa combined with an elongation to failure of 14%.

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Effect ofβ volume fraction on the dynamic grain growth during superplastic deformation of Ti3Al-based alloys

Metals and Materials ◽

10.1007/bf03025974 ◽

1998 ◽

Vol 4 (5) ◽

pp. 1041-1046 ◽

Cited By ~ 8

Author(s):

Ji Sik Kim ◽

Won Jong Nam ◽

Chong Soo Lee

Keyword(s):

Grain Growth ◽

Superplastic Deformation ◽

Volume Fraction ◽

Dynamic Grain Growth

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Grain Refinement in Titanium-Erbium Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052626 ◽

1974 ◽

Vol 32 ◽

pp. 522-523

Author(s):

B. B. Rath ◽

J. E. O'Neal ◽

R. J. Lederich

Keyword(s):

Electron Microscopy ◽

Size Distribution ◽

Grain Refinement ◽

Grain Growth ◽

Volume Fraction ◽

Pure Titanium ◽

Systematic Investigation ◽

Second Phase ◽

Titanium Matrix ◽

Average Size

Addition of small amounts of erbium has a profound effect on recrystallization and grain growth in titanium. Erbium, because of its negligible solubility in titanium, precipitates in the titanium matrix as a finely dispersed second phase. The presence of this phase, depending on its average size, distribution, and volume fraction in titanium, strongly inhibits the migration of grain boundaries during recrystallization and grain growth, and thus produces ultimate grains of sub-micrometer dimensions. A systematic investigation has been conducted to study the isothermal grain growth in electrolytically pure titanium and titanium-erbium alloys (Er concentration ranging from 0-0.3 at.%) over the temperature range of 450 to 850°C by electron microscopy.

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Microstructural characterization of a rapidly solidified Al-Fe-V-Si alloy for elevated temperature applications

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104819 ◽

1988 ◽

Vol 46 ◽

pp. 550-551

Author(s):

R. E. Franck ◽

J. A. Hawk ◽

G. J. Shiflet

Keyword(s):

High Temperature ◽

Elevated Temperature ◽

Grain Growth ◽

Volume Fraction ◽

Microstructural Characterization ◽

Second Phase ◽

Microstructural Stability ◽

Elevated Temperature Strength ◽

Temperature Applications

Rapid solidification processing (RSP) is one method of producing high strength aluminum alloys for elevated temperature applications. Allied-Signal, Inc. has produced an Al-12.4 Fe-1.2 V-2.3 Si (composition in wt pct) alloy which possesses good microstructural stability up to 425°C. This alloy contains a high volume fraction (37 v/o) of fine nearly spherical, α-Al12(Fe, V)3Si dispersoids. The improved elevated temperature strength and stability of this alloy is due to the slower dispersoid coarsening rate of the silicide particles. Additionally, the high v/o of second phase particles should inhibit recrystallization and grain growth, and thus reduce any loss in strength due to long term, high temperature annealing.The focus of this research is to investigate microstructural changes induced by long term, high temperature static annealing heat-treatments. Annealing treatments for up to 1000 hours were carried out on this alloy at 500°C, 550°C and 600°C. Particle coarsening and/or recrystallization and grain growth would be accelerated in these temperature regimes.

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A High-Strain-Rate Superplasticity of the Al-Mg-Si-Zr-Sc Alloy with Ni Addition

Materials ◽

10.3390/ma14082028 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2028

Author(s):

Andrey Mochugovskiy ◽

Anton Kotov ◽

Majid Esmaeili Ghayoumabadi ◽

Olga Yakovtseva ◽

Anastasia Mikhaylovskaya

Keyword(s):

Strain Rate ◽

Volume Fraction ◽

Strain Rate Range ◽

Zener Pinning ◽

Nucleation Effect ◽

Pinning Effect ◽

Ni Addition ◽

Elongation To Failure ◽

Mean Size ◽

High Temperature Tensile

The current study analyzed the effect of Ni content on the microstructure and superplastic deformation behavior of the Al-Mg-Si-Cu-based alloy doped with small additions of Sc and Zr. The superplasticity was observed in the studied alloys due to a bimodal particle size distribution. The coarse particles of eutectic origin Al3Ni and Mg2Si phases with a total volume fraction of 4.0–8.0% and a mean size of 1.4–1.6 µm provided the particles with a stimulated nucleation effect. The L12– structured nanoscale dispersoids of Sc- and Zr-bearing phase inhibited recrystallization and grain growth due to a strong Zener pinning effect. The positive effect of Ni on the superplasticity was revealed and confirmed by a high-temperature tensile test in a wide strain rate and temperature limits. In the alloy with 4 wt.% Ni, the elongation-to-failure of 350–520% was observed at 460 °C, in a strain rate range of 2 × 10−3–5 × 10−2 s−1.

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Size-Dependent Interdiffusion in Nanomaterials

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.101-102.123 ◽

2005 ◽

Vol 101-102 ◽

pp. 123-130 ◽

Cited By ~ 11

Author(s):

Lyudmila N. Paritskaya ◽

Yuri S. Kaganovsky ◽

V.V. Bogdanov

Keyword(s):

Grain Growth ◽

Volume Fraction ◽

Bulk Diffusion ◽

Solution Concentration ◽

Lattice Parameter ◽

Structural Element ◽

Size Dependent ◽

Second Stage ◽

Temperature Homogenization ◽

Two Stages

The phenomenon of low-temperature homogenization (LTH) during interdiffusion is studied under condition a t Dv £ 2 / 1 ) ( (Dv is the bulk diffusion coefficient, a is the lattice parameter) using nano-objects of binary Cu-Ni and Cr-Ni systems compacted from nano-powders and produced by mechanical alloying. Two stages of LTH were detected: at the first stage (t £ 103 s) the volume fraction of solution rapidly grows; at the second stage (t > 103 s) the volume fraction of solutions grows slowly with practically constant average solution concentration. The first stage of LTH correlates with active grain growth caused by small size (l) of structural element and nonequilibrium structure of nano-objects. Obtained results are analyzed theoretically in terms of interdiffusion along migrating GBs due to grain growth at the first stage and DIGM mechanism at the second stage. It is shown that the GB concentration distribution during interdiffusion along migrating GBs and the kinetics of LTH depend on a parameter l/l where 2 / 1 ) / ( b b V sD d l= is the characteristic diffusion length. The mechanisms and criteria of LTH are proposed.

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Variant Selection in Zr Alloys: How Many Variants Generated from one Beta Grain?

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.105.133 ◽

2005 ◽

Vol 105 ◽

pp. 133-138 ◽

Cited By ~ 3

Author(s):

Pierre Barbéris ◽

Frank Montheillet ◽

Cédric Chauvy

Keyword(s):

Elastic Energy ◽

Volume Fraction ◽

Variant Selection ◽

Energy Minimum ◽

Maximum Volume ◽

Volume Fractions ◽

Minimum Number ◽

Simplifying Assumptions ◽

Maximum Volume Fraction ◽

Zr Alloys

The elastic energy of a set of the twelve variants generated during the b ® a transformation of zirconium, with volume fractions fi, i=1..12, is derived with simplifying assumptions and the conditions on the fi to reach the energy minimum are established analytically. The minimum number of variants needed to reach this minimum is shown to be 6, and in this case, the variants have very specific volume fractions. Another result is that the maximum volume fraction of any variant is 1/3.

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