Development Of Rolling Textures Research Articles

Texture development of pure Ti by rolling at various temperatures and its effect on sheet formability

This work investigated the effect of rolling temperature (25–800 °C) on rolling-texture development and sheet formability of pure Ti. The rolling temperature significantly affected the development of the typical transverse-direction (TD)-split basal texture in pure Ti sheet by altering the tilting angle of (0001) basal poles. Notably, a normal-direction (ND) basal texture, where the tilting angle of (0001) basal poles was approximately 0°, developed at an intermediate rolling temperature of 400 °C. This result is remarkable because the ND basal texture is rare in pure Ti. Formation of this unusual ND basal texture was attributed to significant activation of basal <a> slip. In contrast, a typical TD-split basal texture was dominant at the other rolling temperatures. Formation of this typical texture was attributed to pyramidal <c+a> slip. After subsequent recrystallization annealing, sheet formability was examined. Despite their different textures, the sheets previously rolled at the different rolling temperatures showed similar formability. This similarity occurred because any given texture could not simultaneously provide in-plane stretching uniformity and thinning capability during sheet forming. The present study suggests an important guidance for modifying texture of pure Ti sheets to effectively increase their formability.

Investigation of the Microstructure and Rolling Texture Evolution of Cu-45 at.% Ni Alloys during the Recovery Process by Quasi-In Situ Electron Backscatter Diffraction

Investigation of the Microstructure and Rolling Texture Evolution of Cu-45 at.% Ni Alloys during the Recovery Process by Quasi-In Situ Electron Backscatter Diffraction

Effect of roll speed ratio on the texture and microstructural evolution of an FCC high-entropy alloy during differential speed rolling

A very coarse-grained (335 μm) Fe 41 Mn 25 Ni 24 Co 8 Cr 2 high-entropy alloy with a single FCC phase was cold rolling to a 80% reduction in thickness using the differential speed rolling technique with various speed ratios (SRs) ranging between 1 and 4. As the SR was increased, the volume fraction of the region of high-density micro-shear bands increased to accommodate the higher shear strain. At SR = 4, the entire thickness of the sheet was covered with micro-shear bands, and ultrafine (sub)grains with a size of 1.4 μm were uniformly formed along the shear bands. A continuous dynamic recrystallization (CDRX) mechanism occurred during rolling, and a higher SR accelerated the CDRX process. During conventional rolling (at SR=1), a brass { 110 } 〈 112 〉 orientation texture with minor components of S { 123 } 〈 634 〉 and Cu { 112 } 〈 111 〉 orientations developed. At higher SRs, shear texture developed as the main type, while the development of rolling texture was suppressed. The microstructure at SR=4 obtained after annealing at 973 K showed a fully recrystallized microstructure composed of a five times smaller grain size (4 μm) with a higher intensity of γ fiber texture compared with that prepared by conventional rolling. The samples processed with high SRs exhibited better tensile properties compared with the conventionally rolled sample in terms of strength and ductility after annealing. The current results demonstrate that by using differential speed rolling with a high SR, one can achieve a significantly finer and more homogeneous microstructure, stronger shear texture, and superior tensile mechanical properties for an FCC high-entropy alloy compared to that obtained by conventional rolling. The strength of the as-rolled and annealed samples was quantitatively explained by considering the contribution of grain size and dislocation density to strengthening.

Contribution of dislocation substructures developed during cold rolling to the formation of rolling textures in Al–Mg alloys

Abstract In order to investigate the mechanism of the development of rolling textures in Al –Mg alloys, hot bands of high-purity Al, Al-3 wt. %Mg and Al-5 wt. %Mg alloys were solution-treated at 450 °C and cold-rolled by varying rolling reductions up to 97%. Rolling textures of these specimens were investigated with the orientation distribution function analysis. Comparisons of the results of the texture analysis with those of the hardness measurement and transmission electron microscopy observations revealed that, in all specimens, the texture development occurred mainly at the later half of work hardening, i. e., at rolling reductions above 80 %, where dislocation substructures were well developed. In pure Al, in which well defined, elongated cell structures were developed, {112}&lt;111&gt; and {123}&lt;634&gt; components developed remarkably, whereas in the Al-5% Mg alloys, in which only dense dislocation tangles and ill defined small cells were developed, the development of {112}&lt;111&gt; and {123}&lt;634&gt; components was strongly suppressed. All these observations thus suggested that the development of rolling textures was strongly affected by the development of dislocation substructures, which occurred concurrently during rolling, and that the formation of elongated cell structures was more favorable for the development of rolling textures. In cold rolling, elongated cell structures may be the final form of dislocation substructures, providing both mechanical stability and orientation stability.

Rolling texture development in a dual-phase Mg-Li alloy: The role of temperature

Dual-phase Mg-Li alloys sheets were rolled at four different temperatures ranging from liquid nitrogen to 300 °C to explore effect of rolling temperature on texture and mechanical properties of the material. Crystal plasticity simulation was utilized to illustrate the influence of slip activity on rolling texture development. The results show that the rolling texture is largely depended on deformation temperature. Unlike commercial Mg alloys, the critical resolved shear stress of basal slip in α-Mg phase of Mg-Li alloy decreased more significantly by increasing temperature compared to that of pyramidal <c+a> slip. Enhancement of basal slip by increasing temperature triggered a decrease of split angle of basal poles for the double-peak texture. Prismatic <a> slip largely enhanced by increasing temperature upon 200 °C, which induced a wider orientation spread along the transverse direction. For the β-Li phase, the promotion of {110}<111> slip system at elevated temperature triggered the enhancement of {211}<110> and {111}<211> texture components. The cryo-rolled sample exhibited the highest strength compared to the others due to a strong hardening behavior at this temperature. A two-stage hardening behavior was observed in these as-rolled dual-phase alloys. Strain transition at phase boundaries could be the reason for appearance of this two-stage hardening.

Effect of Slab Reheating Temperature on Cold Rolling Texture Evolution of Nb-Containing Grain-Oriented Silicon Steel

Texture control of grain-oriented silicon steel is the key factor to ensure the magnetic properties of the finished product. Nb-containing grain-oriented silicon steel with different slab reheating temperatures was hot rolled followed by single-stage or two-stage cold rolling, and the textures were also analyzed. In the single-stage cold rolling process, as the slab reheating temperature is reduced, the intensity of the rotating cube texture {100}&lt;011&gt; and Goss texture {011}&lt;100&gt; drops, and that of the {111}&lt;112&gt; texture increases. In the two-stage cold rolling process, with the decrease in the slab reheating temperature, the intensity of the {111}&lt;112&gt; texture increases from 4.958 to 6.809. At the same slab reheating temperature, the intensity of the rotating cube texture declines more significantly in the two-stage cold rolling process. Finally, two-stage cold rolling with the slab reheating temperature of 1220 °C is found to be more beneficial for the formation of a sharp Goss texture during the second recrystallization. The magnetic induction intensity B800 of the final product is 1.87 T, and the iron loss P1.7/50 is 1.36 W/kg.

The Influence of a Novel Inorganic-Polymer Lubricant on the Microstructure of Interstitial-Free Steel during Ferrite Rolling

A novel polyphosphate lubricant was used and evaluated during hot (ferrite) rolling of an interstitial-free (IF) steel. The texture evolution of these rolled IF steels have been examined by means of X-ray diffraction (XRD) and electron backscatter diffraction (EBSD) measurements. The polyphosphate lubricant shows an improved lubrication performance in terms of the texture optimization compared with lubricating oil and with unlubricated conditions. The γ-fiber texture is enhanced, and less shear texture is produced. This microstructure is responsible for enhanced drawability of ferrite rolled IF steels. The very high thermal stability of the polyphosphate enabled its use at very high temperatures (from 700 to 800 °C). Rolling temperature exerted limited influence on the resulting rolling texture evolution. The polyphosphate lubricant stabilizes the surface texture and reduces the gradient of shear texture through the thickness. The in-grain shear bands are reduced significantly (48.5%) compared with the unlubricated condition. Measured grain orientations indicate that the favorable texture of {111}&lt;112&gt; along the γ-fiber is developed while the undesired α-fiber texture of {001}&lt;110&gt; is effectively suppressed.

Slip behavior and its effect on rolling texture development in a dual-phase Mg–Li alloy

Microstructure and texture evolution of Mg-8.8 wt%Li-0.8 wt%Zn dual-phase alloy during cold rolling to 70% thickness reduction were investigated. The results showed that both α-fiber and γ-fiber of β-Li phase were enhanced during the cold rolling procedure and {001}<110> was the dominant texture component. A double-peak texture with a large tilt angle of 28° was observed in α-Mg phase. Each peak of this texture component exhibited a wider orientation spread towards the transverse direction. This spread is related to the strong activation of pyramidal II slip. Basal slip was still the dominant slip mode and the activities of pyramidal I and pyramidal II slip were also largely enhanced. Schmid factor analysis and viscoplasitc self-consistent simulation jointly suggests that the development of the rolling texture in α-Mg phase can be ascribed to the competition between basal slip and pyramidal slip.

Grain orientation stability and residual elastic energy induced by intergranular elastic interaction in rolled Al sheet

Plastic behaviors of grains in polycrystalline metals are induced by external loading and affected by intergranular elastic interactions during deformation. A proposed reaction stress (RS) model including the effects of external and intergranular interaction stresses can simulate the behaviours, whereas the necessary equilibria of intergranular stress and strain are reached reasonably. Rolling texture development in roughly elastic isotropic Al as an example is simulated based on the RS model, whereas main texture components can be predicted accurately. The level of intergranular interactions may fluctuate depending on many factors and become stabile as texture forms at higher deformation degree, whereas all grains encounter similar deformation environment. Cube orientation indicates certain stability under the effect of RSs. A portion of elastic strain energy remains around the grains beside normal stored energy after deformation. The energy is orientation dependent and could not be predicted accurately by currently predominant crystallographic deformation theories and models based on Taylor strain principles. The elastic strain energy might affect the recrystallization process.

Influence of Intergranular Mechanical Interactions on Orientation Stabilities during Rolling of Pure Aluminum

Taylor strain principles are widely accepted in current predominant crystallographic deformation theories and models for reaching the necessary stress and strain equilibria in polycrystalline metals. However, to date, these principles have obtained neither extensive experimental support nor sufficient theoretical explanation and understanding. Therefore, the validity and necessity of Taylor strain principles is questionable. The present work attempts to calculate the elastic energy of grains and their orientation stabilities after deformation, whereas the stress and strain equilibria are reached naturally, simply and reasonably based on the proposed reaction stress (RS) model without strain prescription. The RS model is modified by integrating normal RS in the transverse direction of rolling sheets into the model. The work hardening effect, which is represented by an effective dislocation distance, is connected with the engineering strength level of metals. Crystallographic rolling texture development in roughly elastic isotropic pure aluminum is simulated based on the modified RS model, whereas orientation positions and peak densities of main texture components, i.e., brass, copper and S texture, can be predicted accurately. RS σ12 commonly accumulates to a high level and features a strong influence on texture formation, whereas RS σ23 and σ31 hardly accumulate and can only promote random texture. Cube orientations can obtain certain stability under the effects of RSs including σ22. A portion of elastic strain energy remains around the grains. This phenomenon is orientation-dependent and connected to RSs during deformation. The grain stability induced by elastic strain energy may influence grain behavior in subsequent recovery or recrystallization.

Uncharacteristic evolution of copper type texture in the presence of shearable precipitates

Abstract In the present work, development of rolling texture in the presence of shearable precipitates is analyzed using age hardenable aluminum magnesium silicon alloy (AA 6061) and aluminum-copper-lithium alloy (AA 2195). A characteristic Brass type texture evolves upon rolling of AA 6061 alloy containing β’’ (Mg5Si6) precipitates, whereas an unexpected Copper type texture develops upon rolling of AA 2195 alloy containing T1 (Al2CuLi) precipitates. The present work highlights that rolling texture evolution in the presence of shearable precipitates cannot be generalized and depends strongly upon the shearing propensity of these precipitates.

Unique Effect of Carbon Addition on Development of Deformation and Recrystallization Textures in Heavily Cold-Rolled Fe-3%Si Alloys

This study investigated the effects of carbon addition on the development of deformation and recrystallization textures in 3 mass% Si steels cold-rolled by 95% reduction in thickness. A 3% Si steel with 0.016 mass% carbon developed RD // &lt;110&gt; (α-fiber) cold-rolling texture to a much greater extent than a 3% Si steel containing carbon less than 0.0005 mass%, whereas it is well known that the development of α-fiber rolling texture is suppressed by the addition of carbon in steels without silicon. This unique effect of carbon addition in the 3% Si steel appeared to be originated from a change in active slip systems. Straight slip bands were observed in the specimen without carbon, and the active slip plane was identified as {110}. On the other hand, wavy slip bands were observed in the steel containing carbon resulted from the activation of {112} and {123} slip planes in addition to {110}. It was also observed that {411}&lt;148&gt; recrystallization texture developed in the carbon-bearing 3% Si steel. Since the recrystallized grains with {411}&lt;148&gt; orientation preferentially nucleated in the vicinity of highly-strained deformation bands formed in deformed grains having α-fiber orientations, it is concluded that the development of {411}&lt;148&gt; recrystallization texture was resulted from the formation of the α-fiber texture after heavy cold-rolling in the carbon-bearing 3% Si steel.

Effect of Ag, In and AgIn Alloying Additions on Microstructure and Texture of Mg-3Al-1Zn Alloy during Multi-Pass Warm Rolling

In the present investigation the rolling response, microstructure and texture evolution of four Mg alloys during multi-pass warm rolling were evaluated. The nominal composition of the base alloy (alloy-1) was Mg-3Al-1Zn. The alloy-2, 3 and 4 were developed by separate additions of non-rare earth elements Ag and In, and a master alloy 85Ag15In (wt.%) to make target compositions Mg-3Al-1Zn-0.5x, (x = Ag ,In, AgIn). Samples from all four alloys were subjected to multi-pass warm rolling at 300 °C to accumulative reductions of 50, 75 and 90% with 8 minutes inter-pass annealing. For all four alloys, crack free sheets of less than 1 mm thickness were produced successfully with true strain corresponding to 90% reduction. The as-cast microstructures revealed second phase particles at grain boundaries and grains interiors for all alloys. A slight scatter in the size of the deformed grains was observed for alloy-1, 2 and 3 after rolling reductions of 50, 75 and 90%. However, a sustained decrease in grain size with increasing the rolling reductions was only observed in alloy-4, despite inter-pass annealing. XRD macro-texture results of alloy-2 and 3 presented very strong basal texture showing almost concentric contours around normal direction (ND). Such strong sheet texture is attributed to a preferential alignment of basal planes parallel to the sheet surface. On the other hand alloy-1 and alloy-4 revealed a weaker texture with basal poles spread more towards transverse direction (TD) as compared to rolling direction (RD) and may be due to the activation of some &lt;c+a&gt; non-basal slip and twinning in addition to basal slip under the same processing parameters.

Effect of deformation mode, dynamic recrystallization and twinning on rolling texture evolution of AZ31 magnesium alloys

Abstract In order to obtain quantitative relationship between (0002) texture intensity and hot rolling conditions, conventional rolling experiments on AZ31 magnesium alloys were performed with 20%–40% reductions and temperatures within the range of 300–500 °C. Shear strain and equivalent strain distributions along the thickness of the rolled sheets were calculated experimentally using embedded pin in a rolling sheet. Rolling microstructures and textures in the sheet surface and center layers of the AZ31 alloys were measured by optical microscopy (OM), X-ray diffractometry (XRD) and electron back scatter diffraction (EBSD). Effects of the rolling strain, dynamic recrystallization (DRX) and twinning on the texture evolution of the AZ31 alloys were investigated quantitatively. It is found that the highest (0002) basal texture intensities are obtained at a starting rolling temperature of 400 °C under the same strain. Strain–temperature dependency of the (0002) texture intensity of the AZ31 alloy is derived.

Effect of Strain Path on Texture Evolution in Cold Rolled Pure Titanium

The cold rolling texture evolution as a function of strain path in pure titanium with initial typical recrystallized texture has been studied using viscoplastic self-consistent simulations. Three different strain paths, namely unidirectional rolling, two-step cross rolling and multi-step cross rolling have been employed to investigate the effect of strain path change on the evolution of deformation texture. The simulation results indicate that the activation of predominant prismatic slip in unidirectional rolling sample results in the formation of commonly cold rolling fiber texture RD//&lt;10-10&gt; in pure titanium, whereas the increased activity of basal slip over that of prismatic slip is responsible for the strong ND//&lt;hkil&gt; fiber texture in the two cross rolled samples.

Effect of Shear Deformation on Texture Evolution in Rolled Pure Titanium

The cold rolling texture evolution under different strain states caused by coupled effects from different combinations of roll gap geometry and friction in pure titanium with initial typical recrystallized texture has been studied using viscoplastic self-consistent simulations. Under plane strain state, the texture is dominated by a typical cold rolling fiber texture RD//&lt;1010&gt; in pure titanium. However, when shear deformation is induced and increased, RD//&lt;1010&gt; fiber texture is decreased, whereas basal texture (0001)[1010] is increased and a strong partial fiber texture RD//&lt;2110&gt; is formed. The variation of cold rolling texture at different strain states can be ascribed to variation of relative contribution from activation of prismatic, basal and pyramidal slip.

Cold rolling texture evolution of TiB2 particle reinforced Al-based composites by Neutron Diffraction and EBSD analysis

Texture development of particle-reinforced metal matrix materials (P-MMCs) has not been understood well, especially the effects of second-phase particles during the deformation. In this work, we have investigated the texture evolution of TiB2/Al composites during cold rolling by Neutron Diffraction and EBSD analysis. Two forms of TiB2 particles influenced the texture evolution in different ways. The particle-clusters aggregated along grain boundaries led to a reduction of texture volume fraction; recrystallization nuclei with weak texture appeared around these particle-clusters. Small non-shearable TiB2 particles dispersed inside Al matrix contributed to strong Copper texture component at high strains; the individual particles rotated together with Al matrix during the deformation. These revealed effects of particles on the texture development in TiB2/Al composites provide a reference for the texture control of P-MMCs.

Microstructure and Texture Development in Al–3%Brass Composite Produced through ARB

In the present work, aluminum‐3% brass composite sheets are produced by accumulative roll bonding (ARB) process up to nine passes at ambient temperature. Evolution of rolling texture is studied by texture measurement using X‐ray diffraction method. The results show that ARB process leads to the formation of copper ({112} &lt;111&gt;) and Dillamore ({4 4 11} &lt;11 11 8&gt;) as the major texture components. The intensity of copper and Dillamore components enhances to values as high as 19 times that of random with increasing number of passes to 9. It is observed that the 5th pass is a transition in development of the texture components, after which the intensities undergo a drop. The textures are comparable to ARB process of high purity aluminum, indicating that the addition of 3% brass particles do not cause any significant change in the deformation behavior. Electron backscatter diffraction (EBSD) technique is used to examine the microstructure; the results reveal formation of ultrafine grains (UFG), starting in the 3rd pass and covers the entire structure after the 5th pass. The major mechanisms involved are identified as rotation of the sub‐grains, as well as grain boundary migration.

Rolling Texture Simulation of Aluminium Sheets Based on the Mechanism of Intergranule Reaction Stresses

Many efforts have been made to simulate the rolling texture evolution in polycrystalline Al for which strain and stress equilibrium of grains need to be considered. The conventional Taylor theory and its modifications, such as current VPSC, ALAMEL, GIA, fail to solve the problem of stress incompatibility between grains and their surrounding matrix properly. A reaction stress model is suggested for rolling deformation, which accounts both for stress and strain equilibrium and predicts similar textures as those by the Taylor theory. The corresponding detailed modification could reproduced the real rolling texture formation if the industrial rolling stress condition is included.

On the deformation behavior of κ-carbide-free and κ-carbide-containing high-Mn light-weight steel

Light-weight high-manganese steels offer a high potential for industrial application due to their excellent combination of mechanical properties and reduced density. In the present work, the deformation behavior of an Fe-29.8Mn-7.65Al-1.11C steel was investigated by means of TEM microstructure analysis and XRD texture measurements. CALPHAD calculations were used to determine the processing parameters for the applied heat treatments in order to produce essentially different initial microstructures, i.e. single-phase austenite in homogenized condition with large grain size (state A), 2-phase steel composed of austenite and κ-carbides in aged condition with large grain size (state B), and single-phase austenite in recrystallized condition with fine grain size (state C). Since this is the first study to directly compare the plastic deformation of the same alloy with and without κ-carbides, the influence of the precipitation state could be successfully identified. Although the mechanical properties were strongly affected by grain size and precipitation state, the developed deformation microstructures and textures appeared very similar and evidenced the activation of the same deformation mechanisms in the material in states A, B, and C. The strong work hardening in these alloys was facilitated by planar dislocation glide leading to slip band refinement, i.e. Slip band Refinement-Induced Plasticity (SRIP) rather than microband formation. The reasons for this deformation behavior as well as its influence on the evolution of rolling and tensile textures are discussed.