Cube Recrystallization Texture Research Articles

Effects of high magnetic field annealing on the initial recrystallized texture in pure copper

The cold-rolled pure copper sheets were annealed with and without a high magnetic field of 12 T. The results showed that the magnetic annealing could promote the formation of the initial recrystallized cube texture. The magnetic annealing did not dramatically change the final annealing textures, but the intensity of the recrystallized cube texture is obviously different. The differences of the recrystallized cube orientation intensity between the specimens with and without the field annealing may be attributed to the effects of the magnetic field on the mobility of grain boundaries.

Strong cube recrystallization texture in silicon steel by twin-roll casting process

Through-process texture evolution was investigated in Fe–2.8wt.% Si sheets cold-rolled directly from twin-roll cast strip. A strong cube texture ({001}〈100〉) is successfully developed after high-temperature annealing. According to micro-texture analysis, the enhanced cube texture is primarily the result of the frequency advantage of cube recrystallized grains, especially in large grain size ranges, suggesting the dominant role of the oriented nucleation mechanism. Two main types of nucleation sites for cube grains are identified: cube deformation bands in the interior and near the grain boundary of λ (from {001}〈210〉 to {114}〈841〉-{113}〈631〉) deformed regions, and shear bands in {111}〈110〉 deformed matrices. The initial casting texture tends to produce more cube deformation bands and cube shear bands compared with conventional processes. Moreover, the selected processing parameters are favorable for making various nucleation sites work effectively at a very early stage of recrystallization. The results obtained in the present study can provide an efficient way for cube texture control in body-centered cubic alloys.

Texture development and microstructure evolution in metastable austenitic steel processed by accumulative roll bonding and subsequent annealing

In this paper, microstructure and texture development in a Fe–24Ni–0.3C metastable austenitic steel processed by accumulative roll bonding (ARB) and subsequent annealing was studied. Microstructural observations and crystallographic analysis were carried out by FE-SEM/EBSD. The results showed that elongated ultrafine-grained austenite having 300 nm in thickness surrounded by high angle boundaries was obtained after 6 cycles of the ARB process. It was found that 1-cycle ARB-processed specimen exhibited Copper ({112} 〈111〉) component as main texture, while by increasing the number of ARB cycles, it deviated to S component ({123} 〈634〉) at 2 cycles or Brass component ({110} 〈112〉) at 6-cycle. Annealing of 6-cycle ARB-processed specimen at 873 K for 1.8 ks resulted in the formation of an austenite with mean grain size of 2.5 µm having strong Cube recrystallization texture ({100} 〈001〉).

Influence of Sulfur on the Recrystallization and {100}〈001〉 Cube Texture Formation in Fe48%Ni Alloys Tapes

Hyper textured substrate tapes were prepared by cold rolling and annealing of a Fe48%Ni alloys in order to obtain Cube oriented substrate for photovoltaic thin films and superconductor cables in particular. In the present work, the effect of sulfur on recrystallization and sharp Cube texture formation has been investigated. Results show that the formation of Cube texture is favored by the addition of sulfur in the Fe48%Ni alloy. In order to explain this result, the development of Cube texture during recrystallization has been investigated by EBSD, furthermore, the stored energy has been measured using neutron diffraction on the deformed states. It appeared that MnS precipitates are at the origin of hardening that increases the stored energy gap between the Cube component and the other ones. This difference favors the Cube development.

Fabrication of textured Ni–9.3at.%W substrate by electropulsing intermediate annealing method

Sharp cube texture is difficult to obtain in high W content Ni–W alloy substrates used for coated conductors. In this paper, a new method called electropulsing intermediate annealing (EIA) is adopted to optimize the rolling and recrystallization texture of Ni–9.3at.%W substrate. It is found that, compared with conventional intermediate annealing (CIA) at the same temperature, EIA trends to increase the Copper, S and Brass components, suppress the Goss component in rolling texture. Higher cube recrystallization texture is obtained at relatively low temperature by EIA in a shorter time. The effect of EIA on texture is attributed to the enhancement of recovery process resulting from the athermal effects.

Recrystallization Texture of Heavily Cold Rolled Polycrystalline Nickel Sheets with and without Strong Starting Cube Texture

The evolution of texture is studied in high purity (~99.7%) nickel sheets with widely different starting cube texture ({001}) intensities following heavy cold rolling and annealing. For this purpose two nickel sheets with strong and weak starting recrystallization cube texture (SSCT and WSCT, respectively) prepared by Accumulative Roll Bonding and conventional rolling, respectively, followed by annealing are used as the starting materials for subsequent processing. These sheets are cold rolled to 90% reduction in thickness and annealed at different temperatures. Profuse cube oriented bands could be identified in the SSCT nickel sheet after 90% cold rolling as opposed to rather insignificant presence of cube regions in the WSCT nickel sheet. However, the WSCT nickel sheets consistently show stronger cube texture after annealing treatments as compared to the SSCT material. The failure to observe recrystallization cube texture in SSCT is attributed to the inhibited nucleation of cube grains owing to the unfavorable misorientation environment surrounding cube regions in the deformed matrix.

Effects of Widening during Rolling on the Subsequent Recrystallization Kinetics of Copper

Recrystallization kinetics in copper cold-rolled to 90% reduction with and without significant widening was investigated by electron backscatter diffraction. It was found that the recrystallization process was slightly retarded and the development of cube recrystallization texture was largely inhibited in the widening sample. Cube grains were observed to have a growth advantage by a factor of 2 in the non-widening sample, while this growth advantage was not observed in the widening sample. The recrystallization kinetics and the development of cube texture in the two samples are discussed.

Effect of the Heat Treatment on the Cube Recrystallization Texture of Al-Mn-Mg Aluminum Alloy

The evolution of the recrystallized structure and texture of a cold-rolled Al-Mn-Mg alloy with different heat treatments was studied. The alloy with dual-heat treatments at 872 K and 644 K (599 °C and 371 °C) exhibited fast recrystallization and had coarser recrystallized grains and stronger cube texture than the alloy with single-heat treatment at 872 K (599 °C). The differences in microstructures and textures were attributed to the precipitation state. Large particles formed during annealing at 872 K (599 °C) played a randomizing effect on the total recrystallization texture, while smaller particles formed during annealing at 644 K (371 °C) not only enhanced recrystallization of the cold-rolled sheets, but also caused formation of coarse, recrystallized grains with a strong cube texture. The evolution of the coarse grains was due to nucleation of cube-oriented grains.

Effect of Pre-Recovery on Recrystallization Texture in Nickel Substrates for Coated Conductors

Electron backscattered diffraction (EBSD) technology was applied to study the effect of pre-recovery on the recrystallization texture in nickel substrates for coated conductors. Pure nickel (99.999%) was cold rolled by a 95% total reduction, and then samples were annealed at 200 °C for 1 hour and quenched for fully recovery, and finally annealed at 600 °C for 1 hour and quenched in water. The results show that pre-recovery had a strong influence on the formation of cube recrystallization texture. Compared with samples without pre-recovery treatment at 200 °C, samples through pre-recovery treatment can achieve stronger cube texture after recrystallization annealing, and develop more low-angle grain boundaries but less sigma 3 (Σ3) grain boundaries.

Formation of cube texture affected by neighboring grains in a transverse-directionally aligned columnar-grained electrical steel

The formation of stronger cube recrystallization texture in a transverse-directionally aligned columnar-grained electrical steel than columnar-grained ND and RD samples with initial columnar grains' longitudinal axis being along normal and rolling direction respectively was analyzed experimentally and theoretically, and cube texture was indicated to be attributed to the specific deformation and recrystallization behaviors of cube oriented columnar grains. The specific deformation behaviors of cube oriented grains were revealed focusing on the interactions of specially aligned columnar grains in comparison with {001}〈100〉 single crystal and other two kinds of samples. In addition, reaction stress model was selected to simulate the orientation evolution of {001}〈100〉 orientation by cold rolling, and the modeled result coincided with the experimental results and confirmed the effects of neighboring grains.

Formation and Development of Strong Cube Recrystallization Texture in an Aluminium of Commercial Purity

The goal of the present study inspired by previous works on high purity aluminiun was to manufacture aluminium sheets of commercial purity, grade 1050, with a strong cube texture. In this preliminary work on AA1050, sheets which cube volume fraction reaches 65% have been manufactured. Parameters controlling cube orientation development are mainly the solute dragging due to impurities in solid solution and the stored deformation energy. Besides the 85% cold rolling (CR), two extra annealings and a slight cold rolling are introduced in the processing route to increase the cube volume fraction. The cube orientation, whose substructure is equiaxed, is important for its recovery. It develops thanks to the difference of stored energy relative to that of its first neighbors; the slight cold rolling enhances growth of these cube grains.

Texture and Grain Boundary Character Distribution in a Thermomechanically Processed OFHC Copper

The effect of texture on grain boundary character distribution (GBCD) in thermomechanically processed oxygen-free high-conductivity copper has been investigated. Copper samples were cold rolled to a reduction in thickness of 50% and then annealed for 60 min in the range of 400–600°C. GBCD and texture were measured using electron backscatter diffraction. The fraction of special boundaries (Σ3, Σ9, and Σ27) varied from 59% to 71%, with the maximum in the sample annealed at 500°C. The results indicate that cold rolling provided a strong texture of brass type. It was found that the sample annealed at 500°C have texture components of cube, Goss, rotated-Goss, and Y orientations. These texture components were in relation with the formation of annealing twins and Σ3 boundaries. It was also shown that twin-induced GBCD evolution occurred by strain-induced boundary migration, multiple twinning, and conventional recrystallization. Annealing at 600°C caused full recrystallization and grain growth, showing a strong cube recrystallization texture. The grain growth was found to hinder the formation of special boundaries.

Orientation Evolution and Nucleation Mechanism of UFG-Copper Prepared by SD-AARB with Heat Treatment

Ultra-Fine-Grained (UFG) copper strip was prepared by severe deformation method of asymmetrical accumulative rolling bond (SD-AARB) with heat treatment, in which the reduction rate of 1.08 was employed with 50% rolling reduction by six passes(4.8 true strains). The heat treatment was conducted at annealing temperature of 220°C for 5~55 minutes. EBSD and X-ray diffraction were employed to follow the features of texture and orientations. The texture formulation mechanism of deformed copper recrystallized nucleation was studied. The results show that the deformation textures developed in the copper strip by SD-AARB are very similar to those by common the cold rolling process, which is {112}<111>. After the annealing treatment, the strength of the main texture components in the oxygen-free pure copper is decreased along with the extension of recrystallization annealing time, which is C,R,S and B/G texture components. For high energy release rate, grains of all kinds of orientations have the chance of nucleation and growing up, which is different to traditional recrystallized cube texture.

Isothermal annealing of cold-rolled high-purity nickel

Electron backscattered patterns have been employed to reveal the details of the texture evolution in 90%, 95% and 97.5% cold-rolled, polycrystalline, high-purity nickel specimens after 1 h anneals at a variety of temperatures. The results show that increasing the thickness reduction of cold-rolling both strengthened the cube texture developed after primary recrystallization, and increased its thermal stability at elevated temperatures. In the 90% cold-rolled specimens, secondary recrystallization occurred during annealing at 600 °C but could not be completed at temperatures up to 1000 °C. In contrast, extensive secondary recrystallization occurred in 95% and 97.5% cold-rolled specimens that were annealed at temperatures up to 1000 °C. Most of the orientations of the second recrystallized grains were related to the primarily recrystallized cube texture by a 41° rotation around about 〈1 1 1〉 axis or a 27° rotation about 〈2 1 1〉, while a few secondary-recrystallized grains were found to have an 18°/〈1 0 0〉 misorientation relationship with the cube-oriented matrix. It appears that the preferred rotation angles/axes is dependent on the rolling reduction.

Through-thickness texture gradient in continuous cast AA 5052 aluminum alloy sheet

The development of through-thickness texture gradient during continuous cast (CC) processing of AA 5052 aluminum alloy was investigated by X-ray diffraction. The CC slab and the hot bands after each of three rolling passes were obtained from an industrial CC processing operation. The results show that a through-thickness texture gradient exists near the surface after the first pass. The subsurface layer exhibits a very weak texture, while the center layer shows the β fiber rolling texture. After the third pass, a strong β fiber rolling texture is obtained at different through-thickness layers. The roll-gap geometry does not produce any shear deformation at the intermediate layer. After recrystallization annealing, the through-thickness texture gradient still exists in the AA 5052 aluminum alloy sheets. As the measured position moves towards the center from the surface, the cube recrystallization texture strengthens.

Effects of electric field on recrystallization texture evolution in cold-rolled high-purity aluminum sheet during annealing

The effects of an external DC (direct current) electric field on recrystallization texture evolution in the cold-rolled aluminum sheets with 99.99% purity were investigated by means of X-ray diffraction techniques. The cold-rolled high-purity aluminum sheets were annealed for 60 min at 200, 300 and 400 °C, respectively with and without an external DC electric field of 800 V/mm. The results show that with DC electric field, the recrystallization cube texture is strengthened at the stage of grain growth. Possible reason for the strengthening of the recrystallization cube texture with the applied electric field may be attributed to both selected nucleation and selected growth of cube oriented crystal nuclei.

Change in Microstructure and Texture during Annealing of Pure Copper Heavily Deformed by Accumulative Roll Bonding

Pure copper sheets were heavily deformed up to equivalent strain of 4.8 by the accumulative roll-bonding (ARB) processed and then annealed. The ARB processed copper showed the ultra-fine grained microstructure which consisted of relatively equiaxed grains having grain thickness of about 0.2 mm. The DSC measurement of the ARB processed specimens revealed that the recrystallization temperature significantly decreased with increasing the number of the ARB cycles. The stored energy did not increase so much at later stage of ARB, which corresponded with the change in microstructure. The recystallization behavior of the ARB processed copper was governed by discontinuous recrystallization characterized by nucleation and growth process. Remarkable development of cube texture ({100}h001i) was found in the specimen deformed to the equivalent strain of 3.2 or larger and then annealed. The concentration of the cube recrystallization texture depended on the number of ARB cycles. [doi:10.2320/matertrans.MA200701]

Polycrystal-plasticity simulation of six and eight ears in deep-drawn aluminum cups

The formation of earing during cup deep drawing is simulated from crystallographic texture by means of a polycrystal-plasticity model introduced recently [O. Engler, S. Kalz, Mater. Sci. Eng. A 373 (2004) 350–362]. The capabilities of the earing model are validated with five examples of the typical two-, four-, six- and eight-ear profiles of commercial aluminum alloy sheets. Besides analysis of the experimental textures, earing simulations are performed with synthetic textures, including ideal texture components, mixed cube-and-rolling textures as well as computer-simulated rolling textures, in order to study the impact of the various texture components on earing. The polycrystal-plasticity simulations corroborate the common knowledge that four-fold earing with peaks under 0° and 90° are caused by the cube recrystallization texture, while rolling textures produce 45° earing. Mixed textures comprising both cube and rolling texture components lead to more complex cups with eight, six or only two ears, with a smooth transition between these three cases. Transition orientations along the deformation path from the cube recrystallization texture to the rolling texture give rise to an appreciable asymmetry of the cups, where the 0° ears are higher than the 90° ears. This asymmetry results in six-fold earing and, in extreme cases, in two-fold earing with pronounced ears under 0° and 180°.

Biaxially textured constantan alloy (Cu 55 wt%, Ni 44 wt%, Mn 1 wt%) substrates forYBa2Cu3O7−x coated conductors

Commercially available constantan alloy rods (nominal composition Cu55–Ni44–Mn1 wt%)have been thermo-mechanically processed to develop biaxially textured substrates. It wasfound that the (001) recrystallization cube texture percentage could be increased from 72%to nearly 100% as the annealing temperature of the rolled substrates was increased from 750 to1200 °C. A full width half maximum (FWHM) of6.5° in (111) phi scansand an FWHM of 4.9° in (100) omega scans were observed in the substrates annealed at1200 °C for 2 h. These substrates were found to have a Curie temperature of 35 K and so wereparamagnetic at 77 K and ferromagnetic at 5 K with a saturation magnetization that is 2.5times less than that of Ni–5 at.% W substrates. Yield strengths of highly texturedconstantan substrates were found to be 1.5 times that of textured pure Ni substrates atroom temperature.

Texture Evolution and Earing in Aluminium Can Sheet

The texture evolution during hot and cold rolling of AlMg1Mn1 can body sheet is described and the related anisotropy effects during deep drawing are analysed quantitatively. The typical textures of rolled aluminium show the transition between ß-fibre orientations and cube recrystallization texture, depending on rolling temperature and strain. These correlate with transitions between 45° and 0°/90° ear heights in deep drawn cups which are described by a new method of Fourier series expansion. Processing parameters to achieve low anisotropy are discussed.