Solidification Behavior of Aluminum-Copper Based Alloy during Controlled Diffusion Solidification

Controlled diffusion solidification (CDS) is a novel and simple process that enables the formation of non-dendritic microstructure of primary Al phase through mixing two liquid alloys of different composition and temperature together. A quaternary alloy (Al-5.0Cu-0.35Mn-0.25Ti, wt.%), having a similar chemical component with ZL205A, was fabricated using controlled diffusion solidification (CDS) method with different mixing temperature. The mixing temperature of two liquids mostly affects the cast structure especially the primary Al phase. Results show that CDS can reduce the element segregation degree inside the grains. Microstructure evolution during solidification initiates from a primary nucleus firstly and then changed to a non-dendritic grain structure. The thermal analysis confirms the thermodynamic conditions for the formation of non-dendritic grain structure evolution.

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Grain Structure Evolution of Mg Alloy AM60 Influenced by Ca Addition

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.312-315.271 ◽

2011 ◽

Vol 312-315 ◽

pp. 271-276 ◽

Cited By ~ 1

Author(s):

Henry Hu ◽

Qiang Zhang ◽

Xiao Ping Niu

Keyword(s):

Magnesium Alloys ◽

Grain Structure ◽

Structure Evolution ◽

Solidification Behavior ◽

Nucleation Behavior ◽

Creep Properties ◽

Microstructure Evaluation ◽

Ca Addition ◽

Crystal Structural ◽

Interest In Research

The demand for weight reduction in automobiles has generated strong interest in research and development of magnesium applications, especially for powertrain components. Ca-alloyed magnesium alloys have excellent creep properties and can be potentially used for powertrain applications. In order to better understand their solidification behavior, the grain structure evolution of Ca-alloyed magnesium alloys AM60 has been investigated in this study. The results of thermal analysis and microstructure evaluation indicate the occurrence of heterogeneous nucleation of primary magnesium during solidification. The crystal structural analysis suggests that the nucleation behavior of Ca-alloyed AM60 may be attributed to a good crystallographic match of // .

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Studying of Non-Dendritic Microstructure Forming in Controlled Diffusion Solidification

International Journal of Metalcasting ◽

10.1007/s40962-021-00590-y ◽

2021 ◽

Author(s):

Abbas A. Khalaf

Keyword(s):

Dendritic Microstructure ◽

Controlled Diffusion

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A detailed investigation on the grain structure evolution of AA7005 aluminum alloy during hot deformation

Materials Characterization ◽

10.1016/j.matchar.2020.110801 ◽

2021 ◽

Vol 171 ◽

pp. 110801

Author(s):

Congchang Xu ◽

Hong He ◽

Zhigang Xue ◽

Luoxing Li

Keyword(s):

Aluminum Alloy ◽

Hot Deformation ◽

Grain Structure ◽

Structure Evolution

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Physical Based Microstructure Modelling Coupled with Nucleation Theory during and after Hot Forming of AA5083

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.89-91.509 ◽

2010 ◽

Vol 89-91 ◽

pp. 509-514

Author(s):

Pavel Sherstnev ◽

Christof Sommitsch ◽

Stefan Mitsche ◽

Carsten Melzer

Keyword(s):

Aluminium Alloy ◽

Hot Rolling ◽

Volume Fraction ◽

Electron Backscatter Diffraction ◽

Grain Structure ◽

Nucleation Theory ◽

Structure Evolution ◽

Nucleation Sites ◽

Nucleation Mechanisms ◽

Backscatter Diffraction

A physical model based on three types of dislocations and three nucleation sites for recrystallized grain is applied to hot rolling simulation. This model was implemented into a commercial Finite Element (FE) analysis package FORGE 2008 to calculate both the structure evolution during and the recrystallized volume fraction after hot working of aluminium alloy 5083. It is shown that the main nucleation mechanisms in the aluminium alloy are the particle stimulated nucleation (PSN) and nucleation at grain boundaries. Hence the precipitation kinetics during homogenisation was investigated by use of the thermodynamic calculation software MatCalc. To validate the simulation results hot rolling experiments were performed by means of a laboratory mill. The grain structure evolution was analysed by electron backscatter diffraction (EBSD).

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Grain Structure Formation Ahead of Tool during Friction Stir Welding of AZ31 Magnesium Alloy

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.160.313 ◽

2010 ◽

Vol 160 ◽

pp. 313-318 ◽

Cited By ~ 4

Author(s):

Uceu Suhuddin ◽

Sergey Mironov ◽

H. Takahashi ◽

Yutaka S. Sato ◽

Hiroyuki Kokawa ◽

...

Keyword(s):

Friction Stir Welding ◽

Magnesium Alloy ◽

Structure Formation ◽

Material Flow ◽

Boundary Migration ◽

Deformation Mode ◽

Grain Structure ◽

Az31 Magnesium Alloy ◽

Structure Evolution ◽

Friction Stir

The “stop-action” technique was employed to study grain structure evolution during friction-stir welding of AZ31 magnesium alloy. The grain structure formation was found to be mainly governed by the combination of the continuous and discontinuous recrystallization but also involved geometric effect of strain and local grain boundary migration. Orientation measurements showed that the deformation mode was very close to the simple shear associated with the rotating pin and material flow arose mainly from basal slip.

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Grain structure evolution in a 6061 aluminum alloy during hot torsion

Materials Science and Engineering A ◽

10.1016/j.msea.2005.12.018 ◽

2006 ◽

Vol 419 (1-2) ◽

pp. 105-114 ◽

Cited By ~ 43

Author(s):

William H. Van Geertruyden ◽

Wojciech Z. Misiolek ◽

Paul T. Wang

Keyword(s):

Aluminum Alloy ◽

Grain Structure ◽

Structure Evolution ◽

6061 Aluminum Alloy ◽

Hot Torsion

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Reactive Phase Formation in Thin Films: Evolution of Grain Structure

MRS Proceedings ◽

10.1557/proc-403-51 ◽

1995 ◽

Vol 403 ◽

Cited By ~ 5

Author(s):

K. Barmak ◽

C. Michaelsent ◽

J. Rickman ◽

M. Dahmstt

Keyword(s):

Thin Film ◽

Thin Films ◽

Phase Formation ◽

Experimental Studies ◽

Grain Structure ◽

Structure Evolution ◽

Future Research ◽

Polycrystalline Materials ◽

Product Phase ◽

Nucleation Kinetics

AbstractIt is a well known fact that the properties and performance of polycrystalline materials, including polycrystalline thin films, are strongly affected by the grain structure. Therefore, in treating reactive phase formation in these films, it is (or it will inevitably be) necessary to quantify the grain structure of reactant and product phases and its evolution during the course of the reaction. Theoretical models and the conventional view of thin film reactions, however, have been largely extensions, to small and finite dimensions, of theories and descriptions developed for bulk diffusion couples. These models and descriptions primarily focus on the growth stage and to a much lesser extent on the nucleation stage. Consequently, these models and descriptions are not able to treat the development of product phase grain structure. Recent calorimetric investigations of several thin film systems demonstrate the importance of nucleation kinetics (and hence nucleation barriers) in product phase formation and provide quantitative measures of the thermodynamics and kinetics of formation of the product phases, thereby allowing some degree of comparison with reaction models. Furthermore, microstructural investigations of thin-film reactions demonstrate the non-planarity of the growth front and highlight the role of reactant-phase grain boundaries. In this paper, a summary of these experimental studies and recent theoretical treatments, which combine nucleation and growth in an integrated manner, is presented, with particular emphasis on the Nb/Al system. These experiments and models lead to a new view of reactive phase formation and grain structure evolution as one in which the latter is an integral part of the former. Based on this view, directions for future research are discussed.

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