Formation Of Recrystallization Texture Research Articles

The Effect of Annealing Treatment on the Microstructure and Texture of a Cold-Rolled TiNiFe Shape Memory Alloy Tube

The effect of annealing treatment on the microstructure and texture of a Ti50Ni47Fe3 shape memory alloy tube was studied. The results show that the recrystallization process of a cold-rolled Ti50Ni47Fe3 alloy tube occurs at 600 °C. The microstructure changes from long striped grains to equiaxed recrystallized grains. The main texture of the alloy tube is the fiber texture <111> parallel to RD. With the increase in the annealing temperature, the crystal orientation of the alloy gradually turned to (111)<112>, and a series of secondary textures were distributed along the γ orientation line when the alloy was annealed at a lower temperature (450~600 °C). When the alloy was annealed at 650 °C, the growth of recrystallized grains made the grain orientation change, which led to the weakening of the γ-fiber texture and the formation of recrystallization textures.

Influence of Fine Precipitates on Primary Recrystallization Mechanism and Texture Formation in Cold Rolled Fe-3%Si Alloy with Initial Coarse Goss Grains

Influence of Fine Precipitates on Primary Recrystallization Mechanism and Texture Formation in Cold Rolled Fe-3%Si Alloy with Initial Coarse Goss Grains

Influence of Fine Precipitates on Primary Recrystallization Mechanism and Texture Formation in Cold Rolled Fe-3%Si Alloy with Initial Coarse Goss Grains

Influence of Fine Precipitates on Primary Recrystallization Mechanism and Texture Formation in Cold Rolled Fe-3%Si Alloy with Initial Coarse Goss Grains

Correlation between formability, ridging and recrystallization texture development in ferritic stainless steel fabricated by introducing intermediate annealing during cold rolling

Introducing intermediate annealing (IA) during cold rolling is a most promising approach for reinforcing ridging resistance and r-value of ferritic stainless steels, but it usually deteriorates anisotropy of r-value. To solve this problem, the texture evolution, especially recrystallization texture formation at various IA temperatures and its effect on formability and ridging was investigated. During cold rolling, the crystallite appeared along shear band because of the sequential starting of multislip systems, and due to high rotation tendency of shear component {110}〈001〉 towards stable {111}〈112〉 it owned sharp {111}<112 > and {110}<001 > components, and then during annealing, it preferentially induced recrystallized nuclei, and the γ-fiber recrystallization texture having peak intensity near {111}<112 > was formed owing to high grow tendency of preferentially formed {111}<112 > recrystallized grain. Moreover, IA at 850 °C promoted the rotation of crystallites towards stable {111}<112 > during cold rolling before final annealing compared with IA at 950 °C and above, while for IA at 950 °C and above, higher IA temperature was conducive to nucleating randomly oriented grain, and adverse to consuming other deformed grain by {111}<112 > recrystallized grains during final annealing. Therefore, the γ-fiber recrystallization texture in the final sheet gradually weakened and {110}<001 > component first strengthened and then weakened with increasing IA temperature. In addition, the banded grain clusters having similar r-value or those having same orientation and its variants with same sign of ε23 were less distinct and their size was finer in the final sheet after IA at 950 °C than those after other IA temperatures by reason of the occurrence of partial recrystallization at lower temperature and significant grain growth at higher temperature during IA. With increasing IA temperature, average r-value increasingly reduced, while anisotropy of r-value and ridging resistance first heightened and then lowered, which were lower at 850 °C and the optimal matching was realized at IA temperature of 850 °C.

Cellular Automaton‐Based Modeling of Recrystallization Texture Considering Instability Criterion and Nonuniform Boundary Mobility in AA1100 Aluminum Alloy

Herein, the nucleation instability criteria and nonuniform mobility are considered in the 2D cellular automaton simulation to investigate the recrystallization texture of cold‐rolled AA1100. Under the consideration of mechanical instability, the critical driving force for nucleation depends on the differences of the stored energy between a center cell and the neighboring cells. The possible nucleation sites are reduced to 37.5% in comparison with the nucleation model using a constant value of the driving force. The simulation of nucleation reveals that the mechanical instability promotes the formation of recrystallization textures at the expense of neighboring grains with orientations of deformation textures. The nonuniform mobility of high‐angle grain boundaries is implemented in simulation of recrystallization. The enhanced mobility of high‐angle grain boundaries with misorientation of 40°/&lt;111&gt; significantly promotes the growth of grains with orientations of Cube and (recrystallization textures) and inhibits the growth of grain with orientations of C, S, and B (deformation textures).

Formation of recrystallization texture and its effect on deep drawability for high-purified ferritic stainless steel by two step cold rolling

For working out the approach of acquiring low planar anisotropy while achieving high ridging resistance and r-value, during two step cold rolling processes with different total reductions the texture evolution and corresponding mechanism were investigated for ferritic stainless steel. During cold rolling, the crystallites having orientations near {111} 〈112〉 and Goss were induced by shear bands and with further deformation Goss orientation tended to rotate towards more stable {111} 〈112〉. During subsequent annealing, these crystallites induced the recrystallized nuclei and {111} 〈112〉 nuclei consumed preferentially the adjacent matrixes, generating the γ-fiber recrystallization texture having the main component of {111} 〈112〉. With increasing total cold rolling reduction, the γ-fiber recrystallization textures were gradually intensified and band-like grain colonies having approximate r-value and those having variant with ε23 of same sign became more obvious and their distribution more uneven, the average r-value and ridging resistance exhibited a monotonous upward and downward trend, respectively, and the planar anisotropy of r-value first deteriorated and then improved and reached lowest value at 90 %. Considering acceptable ridging resistance in practical application, the excellent deep drawability can be acquired at the total reduction of 90 %.

Quantitative prediction of Al and learning grain boundary character in Al-rich interstitial free steel

It is known that the addition of Al in interstitial free steel has a positive influence on the normal direction fiber recrystallization texture. The location and role of Al in interstitial free steel are not yet clear. Current research shows the likely role of Al in precipitation and/or its location in the grain matrix/grain boundary (0.17 wt% Al) and its impact on the properties. Industrially processed hot-rolled steel subjected to cold rolling (90%) and isothermal annealing validated the formation of normal direction fiber recrystallization texture. Precipitation studies showed no Al-containing precipitates. High-resolution secondary ion mass spectrometry imaging confirmed the presence of Al more on certain grain boundaries in fully recrystallized steel. Molecular statics simulation studies using a large-scale atom/molecular massively parallel simulator showed a reduction in the grain boundary energy with Al addition, assisting the system to reach a minimum energy state.

Crystallographic Laws of Formation of Recrystallization Texture in a Copper Capillary Tube

Crystallographic Laws of Formation of Recrystallization Texture in a Copper Capillary Tube

Effects of Fe, Si, and Cu on Recrystallization Behavior in High Purity Aluminum Foil

The correlation between the recrystallization behavior of high purity aluminum foil, which is used as the electrode material of electrolytic capacitors, and the influence of Fe, Si, and Cu contents on the formation of recrystallization texture was systematically investigated. The following results were obtained: (1) Room-temperature recrystallization, which occurs during cold rolling of the highest-purity material, was suppressed by adding approximately 10 mass ppm of Fe, Si, and Cu. The effect was strongest for Cu, followed by that for Si and Fe. (2) The main component of texture after the final heat treatment changed in the order {001}<100>→ {011 }<411>→> {126}<411>→ {123}<412> as the purity of the aluminum foil decreased. In particular, {126}<411> was an characteristic orientation for extremely coarse grains and was considered to have originated from the rolling texture (β-fiber). This coarse grain growth was considered to be related to the decrease in the growth rate of the recrystallized grains depending on the purity of the matrix.

The role of deformation twins in recrystallization texture formation of the FeGa alloy

It has been found that at cold axial deformation of the (Fe83.4Ga16.6)99.9(NbC)0.1 alloy by hydrostatic extrusion, along with the slip processes, deformation twins are formed. The orientations of these formations in the plane perpendicular to the deformation direction coincide with the crystallographic planes {100} or {110}. It is believed that in bcc alloys, the axial deformation texture <110> is stable and undergoes only a small scattering upon recrystallization. Using the EBSD technique in this work, we have shown that the desired <100> / / DD grains can grow into a deformed <110> / / DD matrix upon primary recrystallization. At the same time, recrystallization of as-deformed samples leads to almost complete destruction of the original texture. The <100> orientation probably develops in connection with the presence of nuclei in the form of the least deformed twins, which are not observed in ordinary iron alloys. This feature of Fe-Ga alloys gives principal possibility of creating necessary cube texture and achieve a high magnetostriction value.

Particle-stimulated nucleation and recrystallization texture initiated by coarsened Al2CuLi phase in Al–Cu–Li alloy

The particles stimulated nucleation (PSN) triggered by coarsened T1 phase (Al2CuLi) in Al–Cu–Li alloys is investigated to analyze the formation of recrystallization texture that is unusual from typical PSN. The specimens were uniaxially compressed to a series of compression amount and the recrystallization process is characterized by electron backscattered diffraction (EBSD), scanning electron microscope (SEM) and transmission electron microscope (TEM). Results showed that the recrystallization occurred by progressive rotation of the matrix units that separated by the three-dimensional arranged T1 precipitates. The rotation of the units towards <001> was observed in the initial grains of various orientations all through the recrystallization process. The massively formed fine grains contribute to a strong <001> fiber texture. The fraction of recrystallization is 67% and the grains are averagely 2.5 μm in the specimen received a stain of 1.61. The PSN initiated by coarsened T1 phase fosters the feasibility to obtain textured and refined structure in Al–Cu–Li alloys which will facilitate the performance improvement of the fabricated components.

On the Texture Weakening During Electropulse Annealing Treatment of Mg-1Ce Alloy: The Role of Nucleation and Nucleus Growth

Mg-1Ce alloys were pre-rolled at room temperature to various reductions to achieve different as-rolled microstructures. The deformed materials were then treated with a pulsed electric current (electropulse treatment, EPT) to study the effect of the as-rolled microstructure on the recrystallization texture formation. The experimental results show that an optimum window exists for pre-rolling reductions, within which the as-rolled microstructures and sharp basal textures obtained will evolve into fine recrystallized grains and weak textures during the subsequent EPT. Microstructure analysis indicates a competition between two processes, the nucleation and the nucleus growth, in contributing to the texture weakening of the alloy. While both the application of pulsed electric current and the increase in the pre-rolling reductions could strengthen the advantage of the nucleation rate of the non-basal nuclei over those with basal orientations, the contribution from nucleus growth depends mainly on the available deformed basal-oriented matrix, which decreases with increasing pre-rolling reductions. The results of the present study might provide useful guidance for the optimization of process parameters in the future application of the ‘pre-rolling + EPT’ technique on the Mg alloy sheet.

Texture evolution in twin-roll strip cast non-oriented electrical steel with strong Cube and Goss texture

Increasing magnetically favorable <100>//ND texture components is a key challenge in the preparation of high-efficiency non-oriented electrical steels. In this study, an Fe-1.3 wt% Si steel with strong Cube ({100}<001>) and Goss ({110}<001>) texture was successfully produced by novel twin-roll strip casting, cold rolling and annealing process. The microstructure and texture of the material was characterized by optical microscopy, electron backscatter diffraction (EBSD) and X-ray diffraction (XRD). The origin and formation mechanism of texture are described from the perspective of deformation and recrystallization behavior of specifically oriented grains. It was observed that initial Cube rotated toward {013}<031>-{110}<110> besides rotation toward {001}<130>-{001}<120> during cold rolling. In addition, new Cube deformation bands were developed in the deformed {115}<051>-{115}<161> grains. Cube components were partly retained as large block, small band structure and crystallite after heavy cold rolling. The Cube deformation structures served as nucleation sites of new Cube grains. The shear band within {114}<110>, {112}<110> and {111}<112> matrix also provided some Cube nuclei. Morphology change from near bar-shaped to equiaxed occurred during the growth of Cube and Goss grains. The formation of recrystallization texture is attributed to the oriented nucleation mechanism, and the orientation pinning and size effects that impacted the intensity of texture component. The low thickness of strip and coarse solidification microstructure with strong {100} texture are the decisive factors to obtain strong Cube and Goss texture in strip-cast non-oriented electrical steel.

Effect of Composition on Recrystallization Texture Formation of Aluminum Extrusions

Effect of Composition on Recrystallization Texture Formation of Aluminum Extrusions

Optimization of grain gene based on texture hereditary behavior of magnetic materials

Since the intrinsic properties of materials are determined by the properties and arrangement of atoms, including crystal structure and defects, there is a strong analogy between material genes and biological genes. Therefore, improving the performance of materials by optimizing their genes is a new idea of material upgrading. The <001> orientation texture is closely related to the magnetic properties of soft magnetic materials. We designed and experimentally demonstrated a gene optimization in an important soft magnetic material by electric current. The reduction of grain boundary hopping energy barrier caused by the distribution of electromagnetic field promoted <001> orientation grain nucleation and growth, which directly improved the initial <001> orientation grain gene, and the inheritance of <001> orientation texture was used to control the formation of recrystallization texture. Therefore, it is possible to utilize the gene optimization technique in many materials upgrading such as metal materials and biological materials according to the differences in electromagnetic properties of microstructures.

Development of Through-Thickness Cube Recrystallization Texture in Non-oriented Electrical Steels by Optimizing Nucleation Environment

Texture evolution of 2.1 wt pct Si non-oriented electrical steel sheets was investigated using macro- and micro-texture analysis. The desirable cube ({001}〈100〉) component successfully dominates the recrystallization texture through sheet thickness. The nucleation sites of cube grains are mainly identified at the interfaces of {001}〈230〉-{001}〈130〉 and {223}〈362〉-{114}〈481〉 oriented deformation bands. The formation of through-thickness cube recrystallization texture can be attributed to the optimization of nucleation environment, featuring quantitative advantage of cube nuclei at both strong plane strain and strong shear strain layers under the superiority of locally low density of cube nuclei.

Fabrication of Fe-2.1 wt.% Si Alloy Sheets with Dominant Goss Texture Through Thickness

Macro- and micro-texture of Fe-2.1 wt.% Si alloy sheets were investigated and analyzed by X-ray diffraction and electron backscattered diffraction techniques. A Goss ({110} ) component accompanied by extremely weak γ ( //ND, normal direction) fiber is successfully formed through the sheet thickness after primary recrystallization and considerable grain growth. Goss grains mainly nucleate at shear bands in various deformed matrices with orientations spreading from //ND to //ND fibers. The formation of dominant Goss recrystallization texture through the thickness can be attributed to the suppression of the nucleation at grain boundaries of γ deformed matrices and the promotion of the nucleation at shear bands in various deformed matrices, based on optimization of the initial texture and microstructure and the applied processing parameters.

Aging Behavior of Aluminum Alloy 6082 Subjected to Friction Stir Processing

The present work examined the effect of artificial aging on the microstructure, texture, and hardness homogeneity in aluminum alloy AA6082 subjected to friction stir processing (FSP). Aging was applied to FSP samples at three different temperatures (150 °C, 175 °C, and 200 °C) for a period of 1 h, 6 h, and 12 h. Microstructure analysis using optical Microscopy (OM) and Electron Back-Scattered Diffraction (EBSD) indicated that FSP produced fine equiaxed grains, with an average grain size of 6.5 μm, in the stir zone (SZ) due to dynamic recrystallization. Aging was shown to result in additional grain refinement in the SZ due to the occurrence of recovery and recrystallization with either increasing aging temperature and/or aging time. An optimum average grain size of 3–4 μm was obtained in the SZ by applying aging at 175 °C. This was accompanied by an increase in the fraction of high-angle grain boundaries. FSP provided a simple shear texture with a major component of B fiber. Increasing aging temperature and/or time resulted in the formation of recrystallization texture of a Cube orientation. In addition, Vickers microhardness was evaluated for the FSP sample, indicating a softening in the SZ due to the dissolution of the hardening precipitates. Compared to other aging temperatures, aging at 175 °C resulted in maximum hardness recovery (90 Hv) to the initial value of base metal (92.5 Hv). The hardness recovery is most likely attributed to the uniform distribution of fine hardening precipitates in the SZ when increasing the aging time to 12 h.

Deformation characteristics and microstructural evolution in friction stir welding of thick 5083 aluminum alloy

The microstructure development in the weld key-hole along the plate thickness was investigated through scanning electron microscope (SEM), electron backscatter diffraction (EBSD), and transmission electron microscopy (TEM) techniques. A fundamental understanding of the contact condition at the tool/workpiece interface in a TriflatTM designed friction stir welding (FSW) tool is presented. The development of grain structure for “stop-action” weld reveals that the plasticized material undergoes complex interacting flows due to the presence of threads and flats. The localized high material velocities induce a significant increase in the strain rate within thread space and thereby tune the Zener-Hollomon parameter. An interesting analogy is drawn between the evolution of the secondary shear zone (SSZ) in a typical metal cutting and the steady state FSW processes. The presence of different morphology of the material filling the thread space is linked to the local variation of the contact state variables along weld thickness. It was found that the contact state is governed by the intrinsic interface characteristics and the mechanical property of the material. It was also shown that the presence of larger particles (> 0.5 μm) is responsible for the formation of high angle boundaries (HAGBs) and random recrystallization texture within the stir zone, reflecting random grain orientation due to particle-stimulated nucleation (PSN).

Effect of Dissolved Carbon on the Recrystallization Texture Formation in Electrical Steels

Effect of Dissolved Carbon on the Recrystallization Texture Formation in Electrical Steels