Weak Basal Texture Research Articles

Comparison of the Strain Rate Sensitivity in AZ31 and WE43 Magnesium Alloys under Different Loading Conditions

The initial texture effect of strain rate sensitivity response in magnesium alloys was studied using the quasi in situ electron backscatter diffraction technique. The strain accumulations, under uniaxial loading of both tensile and compression along the rolling direction, showed strain rate dependency. For the AZ31 magnesium sheets with strong basal texture (max intensity to 11.2), twinning first occurs at the onset of plastic deformation, resulting in macroscopic strain rate insensitivity. With further loading, the strain rate sensitivity significantly increases (with the strain rate sensitivity coefficient m increased from 0.0025 to 0.012), arising from the initiation of slip. For the WE43 alloy sheets with weak basal texture (max intensity to 2.6), the overall deformation is sensitive to strain rate under both tensile and compression. The twinning growth rate and twinned volume fraction have been used to identify whether the process is twin-dominated or slip-dominated during the plastic deformation of a magnesium alloy.

Effects of bimodal basal texture on bending stress and microstructure evolution of Mg−2.6Nd−0.55Zn−0.5Zr alloys

AbstractThe extrusion direction (ED) and transverse direction (TD) samples were cut from Mg−2.6Nd− 0.55Zn−0.5Zr alloy sheet, and the effects of bimodal basal texture on the bending stress and microstructure evolution were investigated. Results showed that the ED sample with weak basal texture possessed much lower bending stress than the TD sample. This anisotropy is attributed to the role of different textures on the evolution of deformation mechanisms and microstructures. For the ED sample with weak basal texture, the dominant deformation mechanisms were basal slip in the majority with minor supplement of tension twin in the inner region while basal slip and prismatic slip in the outer region. In comparison, the TD sample with strong basal texture activated more tension twin in the inner region and more prismatic slip in the outer region. The activation of tension twin promoted the development of 〈0002〉//compression direction type texture with the confined ±30° angle range in the inner region and reduced the emergence propensity of high dislocation density and low angle grain boundaries. The massive activation of tension twin allowed the TD sample to maintain a high strain-hardening capacity, which was the fundamental reason for the high bending stress in this sample.

Simultaneous enhancement of strength and ductility in friction stir welded AZ31 alloy via multi-pass hot-rolling and subsequent annealing

Friction stir welding (FSW) is a new solid-state joining process for joining light metals, such as magnesium (Mg) alloys. However, the texture-induced softening mechanism (in stir zone, SZ) tends to cause the worsening of mechanical properties in FSW Mg alloys. In this work, multi-pass hot-rolling and subsequent annealing is used to ameliorate the FSW AZ31 alloy plate. The results show that multi-pass hot-rolling leads to the c-axes of most grains in the SZ approximately perpendicular to the normal direction (ND) transforming into these almost parallel to the ND, accompanied with multiple twin types. After subsequent annealing, twins, as nucleation sites, promote the formation of new grains with off-basal texture, resulting in the weak basal texture. Compared with the FSW plate and the initial plate, the rolled-annealed FSW plate exhibits a relatively uniform hardness distribution and a “strength-ductility” synergy, which are mainly attributed to an appropriate texture feature and a homogeneous grain structure. This work provides a new idea for the development of new high-performance FSW Mg alloys.

Plastic deformation behavior of a Mg-1.5Zn-0.1Ca (mass%) alloy sheet under different strain paths

Mg–Zn–Ca alloy sheets with weak basal texture are expected to improve the room-temperature press formability of Mg-alloy sheets. The plastic deformation behavior of Mg–Zn–Ca alloy sheets should differ significantly from that of typical Mg-alloy sheets with strong basal texture. However, this has not yet been substantially studied. In this study, the plastic deformation behavior of a rolled Mg-1.5Zn-0.1Ca (mass%) alloy sheet with a thickness of 1 mm is studied experimentally. Tests of uniaxial tension, compression, reverse loadings from tension to compression, and from compression to tension are conducted in the rolling and transverse directions, and the work-hardening behavior and evolution of the Lankford value are investigated. Electron backscattered diffraction measurements are also conducted to examine the texture evolution. Under tension, the stress was less in the transverse direction than that in the rolling direction, and an apparent plateau region appeared only in the transverse direction. Under compression, the stress-strain curves exhibited plateau regions at the initial stage and were similar in the rolling and transverse directions. The Lankford values were less under compression than under tension in both directions. Under reverse loading from compression to tension, sigmoidal curves appeared, irrespective of the loading direction; however, they were more pronounced in the rolling direction than in the transverse direction. Under reverse loading from tension to compression, sigmoidal trends did not occur, irrespective of the loading direction, and the in-plane anisotropy in the work-hardening behavior was small. The mechanisms yielding these macroscopic deformation behaviors are discussed in terms of twinning and slip activities.

Deformation behavior of the Mg–Zn–Zr–Nd–Gd alloy

Gd and Nd added Mg–Rare Earth (Mg–RE) alloys have attracted high-temperature applications due to their excellent combinations of high specific strength, high specific stiffness, good damping capacity, and better creep life. Despite these advantages, such Mg–RE alloys have attracted applications only in the cast form, owing to the difficulty in hot workability. Therefore, to understand the hot deformation behavior of Mg–Zn–Zr–Nd–Gd alloy, the present study correlates the results of hot compression studies with microstructure and texture. Serrated flow behavior is observed due to the dynamic strain aging. Maximum strain rate sensitivity is achieved between 580 K–650 K at lower strain rates 0.001 s−1–0.01 s−1. Dynamic recovery is predominantly active within this range of temperature and strain rate. Dynamic precipitation produces ultra-fine precipitates and leads to the suppression of dynamic recrystallization behavior. All deformed samples develop a relatively weak basal texture with the [0 0 0 1] axis parallel to the compression direction.

Effects of deformation temperatures on microstructures, aging behaviors and mechanical properties of Mg-Gd-Er-Zr alloys fabricated by hard-plate rolling

In this investigation, a high-strength Mg-12Gd-1.0Er-0.5Zr (wt.%) alloy sheet was produced by hot extrusion (HE) and subsequent hard-plate rolling (HPR) at different temperatures. The results indicate that the microstructures of these final-rolled sheets are inhomogeneous, mainly including coarse deformed grains and dynamic recrystallized (DRXed) grains, and the volume fraction of these coarse deformed grains increases as the rolling temperature increases. Thus, more DRXed grains can be found in R-385 °C sheet, resulting in a smaller average grain size and weaker basal texture, while the biggest grains and the highest strong basal texture are present in R-450 °C sheet. Amounts of dynamic precipitation of β phases which are mainly determined by the rolling temperature are present in these sheets, and its precipitation can consume the content of Gd solutes in the matrix. As a result, the lowest number density of β phase in R-450 °C sheet is beneficial to modify the age hardening response. Thus, the R-450 °C sheet displays the best age hardening response because of a severe traditional precipitation of β' (more) and βΗ /βΜ (less) precipitates, resulting in a sharp improvement in strength, i.e. ultimate tensile strength (UTS) of ∼ 518 ± 17 MPa and yield strength (YS) of ∼ 438±18 MPa. However, the elongation (EL) of this sheet reduces greatly, and its value is ∼ 2.7 ± 0.3%. By contrasting, the EL of the peak-aging R-385 °C sheet keeps better, changing from ∼ 4.9 ± 1.2% to ∼ 4.8 ± 1.4% due to a novel dislocation-induced chain-like precipitate which is helpful to keep good balance between strength and ductility.

A new strong and ductile multicomponent rare-earth free Mg–Bi-based alloy achieved by extrusion and subsequent short-term annealing

A new multicomponent rare-earth free low-alloyed Mg-1.0Bi-1.0Mn-1.0Al-0.5Ca-0.3Zn (wt.%) alloy is prepared by low-temperature and low-speed extrusion. The as-extruded sample has an ultra-high yield strength (∼425 MPa) but low elongation-to-failure (∼2.1%) mainly due to a bimodal grain structure containing ultra-fine recrystallized (DRXed) grains and large-sized unDRXed regions with a strong basal fiber texture feature, accompanied by a certain amount of micro-scale second phases (Al8Mn5 and Mg2Bi2Ca) and the uniformly distributed nano-scale α-Mn particles. More importantly, the excellent strength-ductility synergy is realized in the annealed samples after appropriate short-term annealing, and the yield strength and elongation-to-failure can reach ∼378 MPa and ∼16.8%, respectively. The effective inhibition of grain growth by grain boundary co-segregation of solutes and pinning effect of α-Mn nanoparticles is crucial for the annealed samples to maintain the relatively high strength. The formation of a new heterogeneous fibrous structure containing fine/coarse DRXed grains and thin fibrous unDRXed regions, along with weak basal fiber texture and low-density residual dislocations, is a key factor for the annealed sample to significantly enhance the ductility. Hence, such a new high strong and ductile low-alloyed Mg–Bi-based alloy will be helpful for enriching high performance low-cost wrought Mg alloy series to achieve extensive applications in industries.

Effects of asymmetric basal texture on the stretchability and the microstructure variations for the rolled ZK60 magnesium alloy sheet

In order to clarify the asymmetric basal texture effects on the stretchability and the microstructure variations of magnesium alloy sheet, two kinds of stretch forming samples were extracted along the rolling direction (RD) and the transverse direction (TD) from ZK60 magnesium alloy sheet with asymmetric basal texture. Their variations involving the microstructure and the stretch formability were investigated using a visco-plastic self-consistent model, along with the three-dimensional finite element method. The experimental and simulated results together showed that the plastic deformation during stretch forming was concentrated in the central region of the stretch sample. Such plastic deformation was more easily propagated into the surrounding area in the TD sample, making its stretch formability higher by nearly 50.7 % than the RD sample. This was attributed to the weak basal texture in the TD sample which activated more basal slip and tension twinning and consequently increased its hardenability. Additionally, with the variation of the stretch forming behavior, the activation of basal slip narrowed the spread angle of the basal pole for the TD sample, while only increased the basal texture intensity for the RD sample. Moreover, activation of the prismatic slip rotated the <10−10> crystal direction toward the major strain direction (LD), promoting the development of <10−10>//LD-type texture in both samples. These results indicated that the comprehensive stretchability improvement of magnesium alloy sheet required weakening the basal texture symmetrically instead of asymmetrically.

Twinning-mediated texture weakening in a basal-textured Mg-6Al-1Zn (mass%) alloy sheet by a novel cold-sample rolling method

In this paper, we report the use of cold-sample rolling (CSR) processing, which induced a high fraction of double twins and a substantial texture-weakening effect in an Al-concentrated commercial Mg-6Al-1Zn (mass%) alloy sheet. A CSR-processed and subsequently annealed sheet showed a weak basal texture with a broad distribution of the (0001) poles toward the rolling and transverse directions. This led to moderate stretch formability with a limiting dome height of 5.5 mm. High-temperature rolling (HTR) processing has been reported to weaken the basal texture in Mg-Al-based alloy sheets because of the activation of non-basal <c+a> dislocations, resulting in texture weakening. However, the processing induced a relatively low fraction of double twins. Consequently, CSR processing led to a relatively high texture-weakening effect. The results showed that twinning-mediated static recrystallization is essential for texture weakening in Al-concentrated Mg-alloy sheets.

Evolution of microstructure and mechanical properties of ZK60 magnesium alloy processed by asymmetric lowered-temperature rolling

Asymmetric lowered-temperature rolling was applied to the fabrication of fine-grained ZK60 magnesium alloy sheet with weak basal texture along the rolling direction (RD). The results showed that multi-pass lowered- temperature rolling could significantly improve the microstructure homogeneity and refine the grain size. Meanwhile, a fiber texture along the transverse direction (TD) gradually developed during rolling process. Importantly, the shear deformation along the RD made the c-axis of basal plane rotate to the RD, weakening the basal texture along this direction. Influenced by such microstructure variation, the yield strength along the TD continuously increased due to the successive grain refinement and the increased activation of prismatic slips, whereas the uniform elongation decreased owing to the decline of strain hardening ability. In contrast, the continuous weakening of basal texture along the RD increased the activation of soft basal slips, greatly offsetting the strengthening effect contributed by grain refinement and thereby causing the slight decrease of yield strength.

Additive friction stir deposition of AZ31B magnesium alloy

The current work explored additive friction stir deposition of AZ31B magnesium alloy with the aid of MELD® technology. AZ31B magnesium bar stock was fed through a hollow friction stir tool rotating at constant velocity of 400 rpm and translating at linear velocity varied from 4.2 to 6.3 mm/s. A single wall consisting of five layers with each layer of 140×40×1 mm3 dimensions was deposited under each processing condition. Microstructure, phase, and crystallographic texture evolutions as a function of additive friction stir deposition parameters were studied with the aid of scanning electron microscopy including electron back scatter diffraction and X-ray diffraction. Both feed material and additively produced samples consisted of the α-Mg phase. The additively produced samples exhibited a refined grain structure compared to the feed material. The feed material appeared to have a weak basal texture, while the additively produced samples experienced a strengthening of this basal texture. The additively produced samples showed a marginally higher hardness compared to the feed material. The current work provided a pathway for solid state additive manufacturing of Mg suitable for structural applications such as automotive components and consumable biomedical implants.

Enhancement of strength and elastic modulus of Mg-Gd-Y-Zn-Zr alloy by Sn addition

The effect of Sn addition on the microstructure and mechanical properties of Mg-12Gd-3Y-0.5Zn-0.6Zr (wt%) alloys was investigated. The results show that the microstructure of the as-cast Sn-containing alloys consists of α-Mg, Mg24(RE,Zn)5 and Sn3RE5 phases. The Sn3RE5 phases with superior high temperature stability increase with the Sn content. The Young's modulus of Sn3Gd5 and Sn3Y5 compounds are 109.0 GPa and 119.2 GPa, respectively, which results in the elastic modulus of the alloys increasing with the Sn element. Mg-12Gd-3Y-0.5Zn-0.6Zr–2Sn alloy has the highest elastic modulus of 51.3 GPa. The addition of Sn can significantly increase the number density of fine circular β′ phases in peak-aged alloys. Suitable volume fraction of Sn3RE5 phases, fine DRXed grains, weak basal texture and fine precipitates endow the peak-aged Mg-12Gd-3Y-0.5Zn-0.6Zr–1Sn alloy with excellent comprehensive performance, and its elastic modulus, UTS and YTS are 50.4 GPa, 452 MPa and 368 MPa, respectively.

The influence of initial texture, microstructure and deformation behavior on the low mechanical anisotropy of extruded Mg alloy tube

In this study, the extruded Mg–Zn–Mn–Ce–Ca alloy tube with a weak basal fiber texture, i.e. the {0001} plane is distributed along the TD with 0°∼30° deflection towards ED, was fabricated. The alloy tube exhibits a low mechanical anisotropy in the tensile process at room temperature. To clarify the relationship between the weak texture and the low mechanical anisotropy, the microstructure and deformation mechanism of the alloy tube in the tensile process along the ED, 45ED and TD were studied. The results revealed that during yielding, the deformation in ED sample was governed by predominant prismatic slip, and a portion of additional basal slip and lowest pyramidal <c+a> slip, while predominant basal slip and accompanied by a high fraction of prismatic slip and lowest pyramidal <c+a> slip for both 45ED and TD samples. These relatively high additional slips result from the weak texture, which attenuates the deformation differences among the three samples. After yielding, the three samples underwent similar prismatic slip transition and twin nucleation quantity. Additionally, the {0001} plane displayed to converge towards the RD after tensile fracture, which may be related to the twins and intragranular slip. Especially for 45ED and TD samples, relatively high basal slip may cause their {0001} plane to tend to be parallel to the loading direction. In summary, the similar deformation mechanisms governed by weak texture along the three directions resulted in the low mechanical anisotropic of the alloy tube.

On the structure-properties relationship of amorphous and crystalline silica nanoparticles reinforced magnesium matrix nanocomposites

In this study, the structure-properties relationship of magnesium matrix nanocomposites was studied. Using an accumulative extrusion (AE) process, the matrix was reinforced by adding 0.25, 0.5 and 1 wt% crystalline and amorphous silica nanoparticles separately. The mechanical behavior of nanocomposite strips was investigated by hardness and uniaxial compression tests. The results indicated that the Mg/0.5%SiO2-Am had the best room temperature compressive properties. An increase of 28.5% in compressive yield strength after extrusion and 235% after annealing was measured. Ultimate compressive strength (UCS) was increased by 20% without reduction in the nanocomposite ductility compared to the pure magnesium strip. FESEM and OM were used for microstructural analysis and revealed no visible cracks or distinct defects between magnesium layers after AE passes. It is found from the EDS analysis that the reinforcement distribution after the AE process was uniform with few agglomerates. Texture analysis using X-ray diffraction and EBSD after the AE process for samples reinforced with 0.5 wt% of amorphous and crystalline silica nanoparticles indicated a negligible difference in the basal plane orientation of the monolithic and nanocomposite magnesium strips after the AE process along extrusion direction. On the other hand, increasing the basal plane peak intensity after annealing for the sample reinforced with amorphous silica compared to the sample reinforced with crystalline silica indicated a weakening of basal texture. Furthermore, the EBSD analysis showed that amorphous silica nanoparticles are more effective than crystalline silica in grain refinement.

Understanding room-temperature deformation behavior in a dilute Mg–1.52Zn–0.09Ca (mass%) alloy sheet with weak basal texture

The deformation behavior of a weakly textured Mg–1.52Zn–0.09Ca (mass%) alloy sheet during room-temperature uniaxial tensile and bending tests was thoroughly investigated using the electron backscattered diffraction technique and crystal plasticity finite-element method. The sheet exhibited a high elongation to failure of 46.1% along the transverse direction because of the easy activation of basal slips, prismatic slips, and tensile twinning. Although the activities of the basal slips and tensile twinning were suppressed during the tensile deformation along the rolling direction, the sheet showed a satisfactory elongation to failure of 28.2% owing to the activation of the prismatic slips. Notably, the sheet exhibited excellent stretchability with a limiting dome height of 10.1 mm. This was attributed to a small fraction of the basal texture component, which facilitated the basal slips during the stretch formation. However, during the bending deformation, the prismatic slips and tensile twinning became less active than during the uniaxial tension, affording inferior bendability to that of automotive-grade Al alloy sheets. This may help to establish microstructural design guidance for the development of room-temperature formable Mg alloy sheets.

Study on the low mechanical anisotropy of extruded Mg-Zn-Mn-Ce-Ca alloy tube in the compression process

In this study, the extruded Mg-Zn-Mn-Ce-Ca alloy tube with a low compression anisotropy along the ED, 45ED and TD was prepared. The effect of the second phases, initial texture and deformation behavior on this low mechanical anisotropy was investigated. The results revealed that the alloy tube contains the high content (Mg1-xZnx)11Ce phase and the low content of Mg12Ce phase. These second phases are respectively incoherent and coherent with the Mg matrix, and their influence can be ignored. Additionally, the alloy tube exhibited a weak basal fiber texture, where the c-axis was aligned along the 0° ∼ 30° tilt from TD to ED. Such a texture made the initial deformation (at 1.0% ∼ 1.6% strain) of the three samples controlled by comparable basal <a> slip. As deformation progressed (1.6∼9.0% strain), larger amounts of ETWs nucleated and gradually approached saturation in the three samples, re-orienting the c-axis to a 0°∼±30° deviation with respect to the loading directions. Meanwhile, the prismatic 〈a〉 and pyramidal <c+a> slips replaced the dominant deformation progressively until fracture. Eventually, the similar deformation mechanisms determined by the weak initial texture in the three samples contribute to the comparable strain hardening rates, resulting in the low compressive anisotropy of the alloy tube.

Development of corrosion-resistant Mg-Al-Ca-Mn-Zn alloy sheet with good tensile properties and stretch formability

To develop high-performance magnesium alloy sheets for sheet applications in the automotive industry, we investigated the effects of the Al content on the tensile properties, stretch formability, and corrosion resistances of Mg-xAl-0.5Ca-0.4Mn-0.8Zn (mass%, x = 2, 5, 8, AXMZx101) alloy sheets. The addition of 5% Al led to the highest limiting dome height of 6.4 mm. The AXMZ5101 alloy sheet also exhibited a good combination of in-plane isotropic strength and ductility. The 0.2% proof stress and elongation to failure were 193 MPa and 24.2% for the rolling direction and 188 MPa and 23.1% for the transverse direction, respectively. Such moderate Al addition resulted in a significantly improved corrosion resistance with a corrosion rate of 0.18 mm/y after immersion in a 3.5% NaCl solution for 7 days, which was approximately 1/4 lower than that of a commercial Mg-Al-Zn alloy sheet. An in-depth characterization revealed that such a good combination of tensile properties and stretch formability is associated with the small grain size, weak basal texture, high work hardenability, and activation of nonbasal slips and that a high corrosion resistance should be achieved by the formation of a dense oxide-rich layer.

Investigation of the microstructural evolution of the as-extruded Mg–6Zn–1Mn alloy sheets under high strain rate tensile loading

To study the microstructural evolution of the as-extruded Mg–6Zn–1Mn alloy sheets with different initial microstructures during high strain rate tensile deformation, the interruptible tensile tests were performed at the strain rate of 1000 s−1, with controlled strain of 2.5%, 7.5% and 12.5%. The microstructure of the samples was characterized by electron backscatter diffraction and transmission electrical microscopy. The results demonstrate that the microstructural evolution of alloys during high strain rate tensile deformation is strongly influenced by the grain size and texture. Twins are suppressed during deformation in the fine-grained samples with strong basal texture, and only a few tension twins are observed at the large strain. Conversely, tension twins are activated greatly in the coarse-grained samples with the weaker basal texture. Twins are firstly activated at a small strain, and then more twins form and grow up as the strain increases. Regardless of the degree of twinning activity, the plastic deformation of the samples with different initial microstructures under high strain rate tensile loading is mainly provided by dislocation slip, and the dislocation density increases with the increase of strain. Moreover, the large grain size and relatively weak basal texture promote the formation of more dislocations.

Texture, microstructure and mechanical properties of an extruded Mg-10Gd-1Zn-0.4Zr alloy: Role of microstructure prior to extrusion

The homogenized Mg-10Gd-1Zn-0.4Zr (wt.%) alloys with and without the LPSO phases were hot extruded, and then the texture evolution, microstructure and mechanical properties of the extruded alloys were investigated. The initial microstructure (prior to extrusion) containing no LPSO phases or only bulk/lamellar LPSO phases leads to a fully dynamically recrystallized (DRXed) grains, while that containing both the bulk and lamellar LPSO phases results in a bimodal structure with the coarse deformed grains and fine DRXed grains, indicating that the bulk LPSO phases can promote the DRX behavior via particle stimulated nucleation mechanism while the lamellar LPSO phases hamper the DRX behavior. An abnormal texture with <0001> parallel to the extrusion direction is observed in extruded alloys with a large average grain size, while a relatively weak basal texture is observed in small grains. The formation mechanism of this abnormal texture is due to the growth advantage of the DRXed grains with <0001> parallel to the extrusion direction over other grains. The contribution of each strengthening mechanism to the yield strength in four extruded alloys was calculated quantitatively, and the results show that grain refinement and solid solution strengthening mechanisms contribute the most to the yield strength in all extruded alloys. The contributions of dislocation strengthening and the secondary phase strengthening are enhanced in extruded alloys containing bulk LPSO phases, while that of texture strengthening is reduced. This work sheds light on controlling the mechanical properties of the extruded Mg alloys via the LPSO phases and texture.

The dynamics of recrystallized grains during static recrystallization in a hot-compressed Mg-3.2Zn-0.1Ca wt.% alloy using in-situ far field high-energy diffraction microscopy

The poor formability of rolled magnesium (Mg) alloy sheet remains a barrier to its widespread commercial use and is attributed to the strong basal texture that occurs in most mechanically processed Mg alloys. Recent attempts to successfully weaken the texture have been made using Mg-Zn-Ca alloys in combination with post-deformation annealing. The motivation for this work is to understand the evolution of the mesoscale processes that occur during annealing (specifically, static recrystallization) and lead to this texture weakening. Toward this goal, more than 1,200 recrystallized grains were studied during in-situ annealing in an 80% hot-compressed Mg-3.2Zn-0.1Ca wt.% (ZX30) alloy using far-field high-energy diffraction (ff-HEDM). The relative volume, crystallographic orientation, and position of each recrystallized grain emerging within a 1 × 1 × 0.1 mm3vol were tracked throughout static recrystallization. These measurements were used to quantitatively measure the nucleation and growth statistics associated with recrystallized grains as a function of annealing time. The measurements reflected a highly heterogeneous process with individual grain dynamics varying wildly from the average, and they also point to relations between relative grain volume and growth rate (or more accurately, the rate of change of volume) with a peak average rate occurring early in recrystallization (at 22% recrystallized). We also explore whether a recrystallized grain's current state can be used to predict its future growth behaviors with implications for Monte Carlo simulations. Finally, we investigate whether recrystallized grains with specific orientations have preferential nucleation and/or growth, and we find that grains with a weak basal texture have a pronounced nucleation advantage that increases with annealing time, while other grain orientations have a slight growth advantage that diminishes with annealing time.