Continuous and Discontinuous Recrystallization of 6013 Aluminum Alloy

In situ orientation mapping using TEM and calorimetric measurements were carried out to investigate the annealing behavior of cold-rolled 6013 aluminum alloy. The recrystallization of the material can be considered to be a number of processes that correspond to two separate stored energy release peaks. In the temperature range of the peak 1, the deformation zones around the large second-phase particles acted as sites for particle-stimulated nucleation. In the matrix, at the same time, some elongation of grains occurred. The elongated matrix grains appeared because of the reduction of the dislocation density and the annihilation of some low-angle grain boundaries between chains of subgrains lying in layers parallel to the sheet plane. The matrix processes in this temperatures range can be considered forms of continuous recrystallization. The matrix high-angle grain boundaries started to migrate at the temperature range of the peak 2. They moved mostly in the direction normal to the sheet plane. Heating of the sample for an appropriate time at those temperatures resulted in the complete discontinuous recrystallization of the material. The recrystallized microstructure was dominated now by elongated grains, which were a few times thicker than those obtained by annealing at the temperatures of the peak 1.

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Orientation Mapping Study on the Inhomogeneous Microstructure Evolution during Annealing of 6013 Aluminum Alloy

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.163.13 ◽

2010 ◽

Vol 163 ◽

pp. 13-18 ◽

Cited By ~ 8

Author(s):

M. Bieda-Niemiec ◽

Krzystof Sztwiertnia ◽

A. Korneva ◽

Tomasz Czeppe ◽

R. Orlicki

Keyword(s):

Aluminum Alloy ◽

Particle Distribution ◽

Phase Particle ◽

Second Phase ◽

Transmission Electron ◽

Orientation Mapping ◽

Initial Stage ◽

Second Phase Particles ◽

Cold Rolled

Orientation mapping in transmission electron microscope was successfully applied to study microstructural changes at the initial stage of recrystallization in the aluminum alloy with a bimodal second-phase particle distribution. The alloy samples were reversibly cold rolled resulting in the formation of laminar structure with zones of localized strain around large second-phase particles. Orientation mapping and in-situ investigations carry information about the processes which are active in the deformation zones during annealing.

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Preparation of Nano Ti3SiC2/MoSi2 Composite by SPS Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.284-286.2414 ◽

2011 ◽

Vol 284-286 ◽

pp. 2414-2419 ◽

Cited By ~ 1

Author(s):

Jun Cai Zhang ◽

Cheng Chang Jia

Keyword(s):

Mechanical Activation ◽

Particle Diameter ◽

Second Phase ◽

Strong Restriction ◽

Matrix Surface ◽

Second Phase Particles ◽

The Matrix ◽

Strong Repulsion

In this paper, nano-Ti3SiC2/MoSi2 composite, whose second phase was 20-150nm, was in situ prepared by mechanical activation (MA) and SPS process with the quaternary powers of Mo, Si, Ti, and C. The results showed that: (1) matrix MoSi2 has strong repulsion to other elements, which leads to more second-phase particles inside the matrix rather than on the matrix surface; (2) matrix MoSi2 has strong restriction on the growing of the second phase, which makes the particle diameter of the second phase inside the matrix only in 200 nm around, while that over the surface reaches to 800 nm around.

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Effect of Heat Treatments on Microstructure and Properties of Hot Compression Aluminum Alloy 7A04

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.480-481.433 ◽

2011 ◽

Vol 480-481 ◽

pp. 433-436

Author(s):

Mu Meng ◽

Zhi Min Zhang ◽

Jian Min Yu ◽

Xin Kai Li

Keyword(s):

Heat Treatment ◽

Aluminum Alloy ◽

Second Phase ◽

Transgranular Fracture ◽

High Deformation ◽

Microstructure And Properties ◽

T6 Heat Treatment ◽

Second Phase Particles ◽

The Matrix ◽

Fracture Appearance

Aluminum alloy 7A04 compressed at high deformation temperature and large deformation is applied in two different heat treatment (T5 and T6), then microstructure and properties of the alloy after heat treatment are investigated. The mechanical properties are studied by means of the tensile testing and the hardness testing. The microstructure characteristics and the fractorgraphy analysis are respectively investigated with optical microscopy and SEM. The experimental results indicate that after T6 heat treatment, the second-phase particles dispersed in the matrix, which can efficiently improving the strength of the alloy, but reduced the toughness. After T5 heat treatment, the coarse and discontinuous second-phase is distributed along the grain boundary, which can lead to the low strength and high toughness because of the lack of the strengthening phase in the grains. The fracture appearance is intercrystalline fracture after T6 heat treatment, and dimple transgranular fracture after T5 heat treatment.

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x-The Effect of Microstructure on the Corrosion Fatigue Property of A7N01P-T4 Aluminum Alloy Welding Joints

CORROSION ◽

10.5006/2805 ◽

2018 ◽

Vol 74 (11) ◽

pp. 1229-1236

Author(s):

Feng Xiao ◽

Jiangli An ◽

Hui Chen ◽

P. Li ◽

Wei Gao

Keyword(s):

Grain Boundaries ◽

Corrosion Fatigue ◽

Fatigue Property ◽

Short Crack ◽

Al Alloy ◽

Second Phase ◽

Test Results ◽

Second Phase Particles ◽

The Matrix ◽

Almost All

The corrosion fatigue short crack propagation (CFSCP) behavior of A7N01P-T4 Al alloy welded joints in 3.5 wt% NaCl solution has been investigated. The test results indicate that the CFSCP followed a cyclical type of growth. Microscopic study shows that almost all second-phase particles are distributed along the grain boundary areas. These particles were easily dissolved during the corrosion fatigue test, resulting in weak grain boundaries. Therefore, the fatigue short crack will grow along the winding grain boundaries. While the second-phase particles on the grain boundaries were the main factor to cause the intergranular crack. Transgranular cracking may occur to the coarse grains in the matrix, which indicate that grain size also has a strong influence on the CFSCP behavior of A7N01P-T4 Al alloy.

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The role of second phase particles and grain boundaries on recrystallization: Quasi-in situ experiments and modeling in U-10Mo alloy system

Journal of Nuclear Materials ◽

10.1016/j.jnucmat.2021.153445 ◽

2021 ◽

pp. 153445

Author(s):

Jacqueline I. Reeve ◽

Benjamin J. Schuessler ◽

William E. Frazier ◽

David P. Field ◽

Vineet V. Joshi

Keyword(s):

Grain Boundaries ◽

Alloy System ◽

Second Phase ◽

Second Phase Particles ◽

In Situ Experiments

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Behavior of Hydrogen Invasion in Aluminum Alloys from Different Environments

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.409.92 ◽

2011 ◽

Vol 409 ◽

pp. 92-95

Author(s):

Takahito Watakabe ◽

Goroh Itoh ◽

Yuji Hatano

Keyword(s):

Aluminum Alloy ◽

Tritiated Water ◽

Second Phase ◽

7075 Aluminum Alloy ◽

Metallic Materials ◽

Silver Particles ◽

Hydrogen Atoms ◽

Second Phase Particles ◽

The Matrix ◽

Invasion Behavior

Hydrogen embrittlement has been known to occur by invading hydrogen (environmental hydrogen) in some metallic materials under several certain conditions, although the cause has not been clarified yet. To clarify the cause, investigations on the behavior of environmental hydrogen in metallic materials are needed. It has been reported that environmental hydrogen invades 7075 aluminum alloy through the second-phase particles (Al7Cu2Fe). However it has not been clarified yet whether environmental hydrogen invades aluminum through the interface between the matrix and second-phase or through the bulk of second-phase particles. In this study, tritium autoradiography technique, TARG, has been applied to an aluminum alloy containing a single kind of second-phase particles (Al7Cu2Fe), to elucidate the invasion behavior of hydrogen from two different environments: tritiated water and tritium gas. In TARG, hydrogen (tritium) atoms that stay in the vicinity of the surface can be detected as silver particles. Silver particles (hydrogen atoms) were primarily detected on the interface between the matrix and second-phase. Thus most of the invading hydrogen is concluded to be trapped by the interface.

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Nucleation of Recrystallization in Fine Grained AA3104 Alloy Analyzed by SEM and TEM Orientation Mappings

Materials Science Forum ◽

10.4028/www.scientific.net/msf.702-703.324 ◽

2011 ◽

Vol 702-703 ◽

pp. 324-327 ◽

Cited By ~ 1

Author(s):

Henryk Paul ◽

Adam Morawiec ◽

François Brisset ◽

Thierry Baudin

Keyword(s):

Aluminum Alloy ◽

Complex Structure ◽

Second Phase ◽

Grain Coarsening ◽

Fine Grained ◽

Rotation Axes ◽

Sem And Tem ◽

Orientation Mapping ◽

Second Phase Particles ◽

Type Relation

This paper describes nucleation and grain coarsening at very early stages of recrystallization in AA3104 aluminum alloy containing complex structure of second phase particles. Measurements of individual sub-cell orientations in ECAP-processed and slightly annealed structures were possible by using TEM-based orientation mapping in combination with recrystallization carried out in the microscope. The results were compared with those obtained by SEM/EBSD system. The investigation shows that the 40o<111>-type relation occurs rarely, and the rotation axes of misorientations between deformed and recrystallized areas were strongly scattered. Grouping of the misorientation axes near the <012>, <221>, <112> and <110> crystallographic directions was noticeable.

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Polishing process effect on the image of dispersed precipitates

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100112646 ◽

1984 ◽

Vol 42 ◽

pp. 534-535

Author(s):

C.T. Hu ◽

C.W. Allen

Keyword(s):

Matrix Material ◽

Specimen Preparation ◽

Second Phase ◽

Precipitate Particle ◽

Polishing Process ◽

Second Phase Particles ◽

The Matrix ◽

Surface Profiles ◽

Thinning Process

One important problem in determination of precipitate particle size is the effect of preferential thinning during TEM specimen preparation. Figure 1a schematically represents the original polydispersed Ni3Al precipitates in the Ni rich matrix. The three possible type surface profiles of TEM specimens, which result after electrolytic thinning process are illustrated in Figure 1b. c. & d. These various surface profiles could be produced by using different polishing electrolytes and conditions (i.e. temperature and electric current). The matrix-preferential-etching process causes the matrix material to be attacked much more rapidly than the second phase particles. Figure 1b indicated the result. The nonpreferential and precipitate-preferential-etching results are shown in Figures 1c and 1d respectively.

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Recrystallization in Ultra-Fine Grain Structures of AA3104 Alloy Processed by ECAP and HPT

Materials Science Forum ◽

10.4028/www.scientific.net/msf.715-716.346 ◽

2012 ◽

Vol 715-716 ◽

pp. 346-353

Author(s):

H. Paul ◽

T. Baudin ◽

K. Kudłacz ◽

A. Morawiec

Keyword(s):

High Pressure Torsion ◽

Deformation Mode ◽

Second Phase ◽

Orientation Measurement ◽

Angular Pressing ◽

Second Phase Particles ◽

Average Grain Size ◽

The Matrix ◽

Electron Microscopes ◽

Different Strains

The objective of this study was to determine the effect of deformation mode on recrystallization behavior of severely deformed material. Commercial purity AA3104 aluminum alloy was deformed via high pressure torsion and equal channel angular pressing to different strains and then annealed to obtain the state of partial recrystallization. The microstructure and the crystallographic texture were analysed using scanning and transmission electron microscopes equipped with orientation measurement facilities. The nucleation of new grains was observed in bulk recrystallized samples and during in-situ recrystallization in the transmission microscope. Irrespective of the applied deformation mode, a large non-deformable second phase particles strongly influenced strengthening of the matrix through deformation zones around them. It is known that relatively high stored energy stimulates the nucleation of new grains during the recrystalization. In most of the observed cases, the growth of recrystallized grains occurred by the coalescence of neighboring subcells. This process usually led to nearly homogeneous equiaxed grains of similar size. The diameter of grains in the vicinity of large second phase particles was only occasionally significantly larger than the average grain size. Large grains were most often observed in places far from the particles. TEM orientation mapping from highly deformed zones around particles showed that orientations of new grains were not random and only strictly defined groups of orientations were observed.

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