Effect of chemical composition and grain size on RT superplasticity of Zn-Al alloys processed by ECAP

Grain refinement is a critical technology for the successful production of cast parts; whether that be preforms such as extrusion billet or rolling slab, or near net-shape castings. A refined microstructure has many advantages with reduced defects and improved mechanical properties. This article describes the approaches to the prediction of grain size in Al-alloys refined by Al-Ti-B master alloys. Included are empirical approaches based on the generation and analysis of grain size data, the development of analytical equations, and the use of finite element approaches to the prediction of grain sizes. It is clear that researchers have a good ability to predict grain size of Al-alloys grain refined by Al-Ti-B master alloys, although there are still some outstanding challenges, particularly in considering more extreme solidification conditions and poisoning of the master alloys.

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Modern quantitative microstructure analysis on the example of aicu5mg1 alloys

Acta periodica technologica ◽

10.2298/apt0233109b ◽

2002 ◽

pp. 109-114

Author(s):

Biljana Zlaticanin ◽

Branislav Radonjic ◽

Branka Jordovic

Keyword(s):

Grain Size ◽

Chemical Composition ◽

Linear Method ◽

Titanium Content ◽

Mean Value ◽

Grain Refining ◽

Relative Standard ◽

Method Of Measurement ◽

The Mean ◽

Picture Analysis

Using an automatic, QUANTIMET 500 MC, device for quantitative picture analysis and applying linear method of measurement on the example of AlCu5Mg1 alloys, the grain size (min, max and medium values), as well as relative standard measuring errors (RSE), dendrite arm spacing (DAS) and length eutectic (Le) and also distribution by size (histogram) and volume participation of ?-hard solution and eutectic have been determined. We have also studied the influence of grain-refining additives AlTi5B1 for the same chemical composition of the aluminium-capper-magnesium alloy. It has been concluded that with the increase of titanium content, the mean value of grain size decreases. We have also examined hardness and pressure strength.

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Correlation of Grain Size, Stacking Fault Energy, and Texture in Cu-Al Alloys Deformed under Simulated Rolling Conditions

Advances in Materials Science and Engineering ◽

10.1155/2015/953130 ◽

2015 ◽

Vol 2015 ◽

pp. 1-12 ◽

Cited By ~ 5

Author(s):

Ehab A. El-Danaf ◽

Mahmoud S. Soliman ◽

Ayman A. Al-Mutlaq

Keyword(s):

Grain Size ◽

Strain Hardening ◽

Mechanical Twinning ◽

Al Alloys ◽

Stacking Fault ◽

Stacking Fault Energy ◽

Wide Range ◽

Orientation Density ◽

Pure Cu ◽

Strain Hardening Rate

The effect of grain size and stacking fault energy (SFE) on the strain hardening rate behavior under plane strain compression (PSC) is investigated for pure Cu and binary Cu-Al alloys containing 1, 2, 4.7, and 7 wt. % Al. The alloys studied have a wide range of SFE from a low SFE of 4.5 mJm−2for Cu-7Al to a medium SFE of 78 mJm−2for pure Cu. A series of PSC tests have been conducted on these alloys for three average grain sizes of ~15, 70, and 250 μm. Strain hardening rate curves were obtained and a criterion relating twinning stress to grain size is established. It is concluded that the stress required for twinning initiation decreases with increasing grain size. Low values of SFE have an indirect influence on twinning stress by increasing the strain hardening rate which is reflected in building up the critical dislocation density needed to initiate mechanical twinning. A study on the effect of grain size on the intensity of the brass texture component for the low SFE alloys has revealed the reduction of the orientation density of that component with increasing grain size.

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Features for friction stir welding of butt joints of casting VAL8 alloy with wrought 1565chN2 and AMg6M alloys

Blanking productions in mechanical engineering (press forging, foundry and other productions) ◽

10.36652/1684-1107-2021-19-10-441-449 ◽

2021 ◽

pp. 441-449

Author(s):

V.A. Berezina ◽

V.V. Ovchinnikov ◽

E.V. Luk'yanenko

Keyword(s):

Grain Size ◽

Tensile Strength ◽

Friction Stir Welding ◽

Chemical Composition ◽

Arc Welding ◽

Butt Joints ◽

Friction Stir ◽

Discrete Nature ◽

Casting Aluminum ◽

Tool Rotation

The results of technological features for friction stir welding of butt joints of sheet blanks with thickness of 3 mm made of casting aluminum V AL8 alloy with wrought magnalium group 1565chN2 and AMg6M alloys are presented. It is established that the time resistance of the joints depends on the location of the welded alloys relative to the direction of tool rotation during friction stir welding. The ultimate strength of welded joints of VAL8 alloy with 1565chN2 and AMg6 alloys in automatic argon-arc welding is 0.82...0.84 of the ultimate tensile strength of VAL8 alloy. The grain size in the stir zone practically does not depend on the initial grain size in the alloys to be joined. The destruction of the joints made of VAL8 + 1565chH2 alloys under cyclic loading has multi-focal character and is initiated from irregularities on the surface of the weld. The discrete nature of the change in the chemical composition of the weld metal along the axis of the weld is revealed. The weld is formed by alternating strips of connected alloys with width of 30...90 microns.

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Influence of thermomechanical processing on the grain size, texture and mechanical properties of Mg-Al alloys

Metallic Materials ◽

10.4149/km_2012_1_1 ◽

2012 ◽

Vol 50 (01) ◽

pp. 1-23

Author(s):

B. SRINIVASARAO ◽

J. A. DEL ◽

O. A. RUANO ◽

M. T. PÉREZ-PRADO

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Thermomechanical Processing ◽

Al Alloys

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Influence of chemical composition, grain size, and spray condition on cavitation erosion resistance of high-velocity oxygen fuel thermal-sprayed WC cermet coatings

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2020.125881 ◽

2020 ◽

Vol 394 ◽

pp. 125881 ◽

Cited By ~ 1

Author(s):

Akihiro Kanno ◽

Kaito Takagi ◽

Masayuki Arai

Keyword(s):

Grain Size ◽

Chemical Composition ◽

High Velocity ◽

Cavitation Erosion ◽

Erosion Resistance ◽

High Velocity Oxygen Fuel ◽

Cermet Coatings ◽

Cavitation Erosion Resistance ◽

Oxygen Fuel

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Influence of Stacking Fault Energy on the Microstructures and Grain Refinement in the Cu-Al Alloys during Equal-Channel Angular Pressing

Materials Science Forum ◽

10.4028/www.scientific.net/msf.667-669.379 ◽

2010 ◽

Vol 667-669 ◽

pp. 379-384 ◽

Cited By ~ 2

Author(s):

X.H. An ◽

Shi Ding Wu ◽

Z.F. Zhang

Keyword(s):

Grain Size ◽

Grain Refinement ◽

Equal Channel Angular Pressing ◽

Al Alloys ◽

Stacking Fault ◽

High Recovery ◽

Angular Pressing ◽

High Recovery Rate ◽

Refinement Mechanism ◽

Stacking Fault Energies

The microstructural evolution and grain refinement of Cu-Al alloys with different stacking fault energies (SFEs) processed by equal-channel angular pressing (ECAP) were investigated. The grain refinement mechanism was gradually transformed from dislocation subdivision to twin fragmentation with tailoring the SFE of Cu-Al alloys. Concurrent with the transition of grain refinement mechanism, the grain size can be refined into from ultrafine region (1 m~100 nm) to the nanoscale (<100 nm) and then it is found that the minimum equilibrium grain size decreases in a roughly linear way with lowering the SFE. Moreover, in combination with the previous results, it is proposed that the formation of a uniform ultrafine microstructure can be formed more readily in the materials with high SFE due to their high recovery rate of dislocations and in the materials with low SFE due to the easy formation of a homogeneously-twinned microstructure.

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