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The precision fabrication of ceramic moulds for the mass-production of micro/meso-structural arrays places a tremendous challenge to the manufacturing industry. This work aims to reveal the physics behind the processes so as to address this technological challenge. A new method for texturing the diamond grinding wheel surface with a micro-abrasive waterjet is proposed for highly efficient form-grinding of ceramic moulds into the required micro/meso-structural surfaces. It shows that this technology provides some unique advantages in improving the sharpness and geometrical accuracy of the grinding wheels. The mechanisms about material removal and texture formation in grinding wheel truing are investigated to enable the precise control of micro/meso-structure generation on the grinding wheel. A theoretical model is established to study the effect of grinding wheel surface micro/meso-textures and grain trajectory on the quality of the ground mould surface and reveal the reflection mechanism of the ground marks on the mould surface. Furthermore, an integrated rough-fine grinding strategy is proposed which is shown to significantly increase the grinding efficiency by 15–24 times. It is found that ductile domain grinding of ceramic moulds to achieve the required contour profile of 6.7 μm PV accuracy and a surface roughness Ra of less than 40 nm can be achieved.

This paper investigates texture formation in titanium prepared by powder metallurgy – namely by cryogenic milling and the subsequent spark plasma sintering. Transmission Kikuchi diffraction was used for the investigation of the milled powder particles, the sintered material was studied by electron backscatter diffraction. Titanium remains ductile during cryomilling, which results in the flattening and repetitive shear deformation of the particles. The observed texture can be explained on the basis of the rolling texture in the titanium. Due to the shape of the milled powder particles, the texture is transferred to the sintered material. The achieved results may be relevant to other ductile metallic materials prepared by milling and subsequent consolidation.

Uniaxial compression tests are carried out in the M1 magnesium alloy at 723K under a strain rate of 5.0x10-2s-1 up to a strain of-1.3. Microstructure observation shows that grain distribution is heterogeneous and coarsened grain is observed in all deformation conditions. Mean grain size tends to decrease with increasing strain. Dynamic recrystallization and grain growth are occurred during deformation. (0001) texture which shown at annealed state is weakened with increasing strain, and texture component changed from (0,0) to (24,0) during deformation. The recrystallized grains have no strong preferred orientation about (0001), similar to the grains of growing.

In previous study, it was investigated texture formation behaviour of high-temperature plane strain compression test at 723K, under a strain rate of 5.0. It was found that the main texture component and it was sharpness vary depending on deformation conditions. To clarify the characteristic of texture formation behaviour, it is necessary to investigate at various deformation condition. Therefore, in this study, is investigating the influence or texture formation behaviour and strain, strain rate at 673K. Three kinds of specimens with different initial textures were machined out from a rolled plate having a texture. The plane strain compression tests were conducted at a temperature 673K, and a strain rate of 5.0, with strain between-0.4 to-1.0. After compression tests, the specimens were immediately quenched in oil. The texture evolution was conducted by the Schulz reflection method using Cu Kα radiation and EBSD. Before the deformation, {0001} of specimen A was accumulated in the center of pole figure. The {0001} of specimen B was accumulated at the RD direction. The {0001} of specimen C was accumulated TD direction. As a result, work softening is observed in all the cases at the true stress – true strain curve for three types of specimens. After deformation, the maximum pole density of increases with increasing strain. In this study, it was found that the stable orientation was (0001) and (0001) during deformation.

In this paper, we show a novel method to obtain small size textures usable in crystalline silicon (c-Si) solar cells. SiO2-based glass microparticles are mixed with a conventional KOH-based alkaline solution for making the textures. Using this mixing method, the texture size can be drastically reduced from 10 to ≤2 µm (0.3–2 µm). In addition, the process time and c-Si loss during the texture formation are reduced from 25 to 2 min and from 20 to 2 µm, respectively. Thus, the process is applicable to c-Si with thickness down to 50 µm. High-quality passivation showing the effective minority carrier lifetimes (τeff) larger than several ms and effective antireflection coating are possible on the new textures. The process is named “microparticle-assisted texturing (MPAT) process”, and its features are also demonstrated.

The Goss texture, or {110}, shows soft magnetic property due to the . Therefore, it is one of the most important texture in Si steels. The Goss texture is one of the shear deformation texture in steel which has bcc structure. During the asymmetric rolling, shear deformation is imposed on steel sheets. To obtain the Goss texture, the carbon and Si steel sheets were asymmetrically rolled by 50-85% reduction in thickness at room temperature and at 770 °C. The asymmetric rolling of steel sheets gave rise to the well-developed Goss texture to them.

Sun S., Hagihara K., Nakano T.. Effect of scanning strategy on texture formation in Ni-25 at.%Mo alloys fabricated by selective laser melting. Materials and Design, 140, 307. https://doi.org/10.1016/j.matdes.2017.11.060., Variations in the crystallographic texture in Ni-25 at.%Mo alloys fabricated by selective laser melting with different scanning strategies were designed for the first time. Single-crystalline-like texture with a short-range order of Mo atoms can be produced via bidirectional scanning along one axis (X-scan) and bidirectional scanning with a 90° rotation in each layer (XY-scan), while only fiber texture was formed in bidirectional scanning with a 67° rotation (Rot-scan). The aligned crystal orientation along the build direction can be varied by the scanning strategy; 〈001〉 is preferred in the XY- and Rot-scan samples, while 〈101〉 is preferred in the X-scan sample. The controlling mechanisms of the texture, focusing on the preferential growth directions of the columnar cells and the following epitaxial growth, are discussed.

Textured growth of Co-Fe-Ga (CFG) alloy films by co-precipitation, low-temperature heat treatment (LTHT) at 333 K for 3 days, spin-coating, and post-annealing at 973 K for 30 min has been investigated. The X-ray diffraction measurements show that the CFG films made with LTHT are highly (1 1 0)-oriented bcc alloys, while those grown without LTHT are not oriented in a specific direction. The observed texture formation in the bcc alloy films results from topotactic transformation as indicated by the similarity of the ionic and atomic arrangements among the precursor, spinel oxide, and bcc alloy. The stabilization of the precursor by Ga3+ inclusion presumably plays an important role in the transformation process leading to the highly orientated spinel and CFG bcc alloy films.

The effect of intensifying Goss texture and refining Goss grains on the enhancement of fatigue crack propagation (FCP) resistance in an Al-Cu-Mg alloy was systematically investigated. The way to improve fatigue performance mainly includes two steps: intensifying Goss texture component and then refining these Goss grains. Hot rolling at elevated temperature and pre-solution treatment are capable of Goss texture formation. Then large cold rolling reduction can refine grains and obtain more these Goss grains, which increases the twist angle boundary components with their adjacent grains to enhance fatigue crack deflection and FCP resistance. By contrast, refining Brass etc. rolling-oriented grains can increase the tilt angle boundary components and promote fatigue crack growth. And the reason why grain refinement cannot always improve fatigue properties in alloys with micrometer grains can depend mainly on grain orientations and the relative boundary components in this Al-Cu-Mg alloy. Besides, coarse Fe-, Si- and Mn-rich inclusions are detrimental to fatigue properties, but the fine, globular and homogeneous distribution of these particles can improve fatigue properties to some extent.

In order to understand the effects of the solute element and its concentration on the formation of texture, uniaxial compression tests were carried out at various deformation conditions with different aluminum solute concentration in rolled AZ magnesium alloy (AZ31, AZ61, AZ91). To clarify the texture measurements and crystal orientation distribution, X-ray diffraction methods were conducted on mid plane section of the specimens. As a result in this study, the formation of fiber texture and occurrence of dynamic recrystallization were observed in all case of specimens. The main components and its sharpness of texture were varied depending on deformation conditions and Al concentrations. Especially, accumulation of basal texture was developed with an increasing of Al concentration.

The present study investigates the effect of cryo-rolling process, i.e. cold-rolling at liquid-nitrogen temperature followed by heat treatment, on tensile properties of pure copper and precipitation-hardened CuCrZr alloy. The cryo-rolling process resulted in a simultaneous improvement of strength and ductility of pure copper. On the other hand, a cryo-rolled CuCrZr alloy showed higher tensile strength but comparable ductility with a conventional cold-rolled CuCrZr alloy. Microstructural analysis indicates that the drastically-beneficial effect of cryo-rolling on pure copper may be due to its heterogeneous size distribution of grains which consist of cryo-rolled fine grains, residual cryo-rolled grains and recrystallized coarse grains. The modest but certain benefit of cryo-rolling on CuCrZr alloy can be explained by different texture formation compared with conventional cold-rolling. Effect of neutron irradiation on tensile properties of cryo-rolled CuCrZr alloy is also examined.

The present paper gives a concise overview of a number of current issues in the literature on texture formation in alloys with cubic crystal structures, mainly steel and aluminium alloys. As crystallographic texture determines to a large extent the anisotropy of material properties, it is of paramount importance to understand and control the physical mechanisms by which the texture is formed in the subsequent stages of metals manufacturing processes. In the present overview three key solid-state transformation processes are considered: allotropic phase transformations, plastic deformation and recrystallisation. The intention is to highlight a number of key elements in the literature and some recent tendencies, which may provide some insight to scientists and engineers dealing with texture issues in daily practice.

New finite element homogenization model with nonaffine constitutive equation of rubber is developed to study the deformation behavior of silica-filled rubber under monotonic and cyclic deformation. The obtained results clarified the effect of the volume fraction of the silica coupling agent and the networklike structure connecting the silica particles on essential physical enhancement mechanisms of deformation resistance and hysteresis loss for silica-filled rubber. The finding suggests that the material characteristics of silica-filled rubber are much more controllable than those of carbon-black-filled rubber.

The cold rolling and annealing texture formation has been investigated in electro deposited pure iron which has an extremely sharp and isotropic //ND fiber. Regardless of cold rolling reduction, {111} intensified texture is formed after cold rolling. Similar texture remains after recrystallization in 65% cold rolled material while {111} type texture forms in 80% and 90% cold rolled ones. The recrystallized grains at the stage of 5% recrystallization have {111} orientation in 65% cold rolled sheet, whereas {111} is observed in 80% cold rolled one. From this aspect, it is considered that the nucleation orientation plays an important role in the recrystallization texture formation. In the meanwhile, the growth of the recrystallized nuclei is also supposed to affect the recrystallization texture formation. The nuclei with {111} orientation in lightly cold rolled sheet are easier to consume the deformed matrix than they do in heavily cold rolled sheets because their frequency to encounter a deformed grain with nearly the same orientation is much smaller in lightly cold rolled specimen, which can result in a large mobility for growth. Cross cold rolling makes cold rolling texture rather homogeneous //ND fiber, which gives rise to an almost homogeneous //ND fiber after annealing.

The uniaxial compression test was used to assess an influence of the precipitate nature on the flow stress, work hardening and texture of the Al–7%Si–1%Cu–0.5%Mg alloy, modified with micro-additions of V, Zr and Ti. A semi-empirical model, adopted to interpret the work-hardening rate during plastic deformation, was capable to predicting the contribution of shearable and non-shearable precipitates to the dislocation-induced hardening during compression. A development of the crystallographic texture was also measured and correlated with deformation behavior of the alloy. The weak texture of {0 1 1}〈2 1 1〉 and {1 1 1}〈1 1 0〉 components, detected after casting, transformed to nearly randomized texture after heat treatment. A room-temperature compression deformation of the as-cast, solution treated and T6 aged alloys resulted in a texture consisting of a mixture of {0 0 1}〈1 1 0〉 and {1 1 1}〈1 1 0〉 components with varying intensities depending on the state of precipitation. An additional {1 1 2}〈1 1 0〉 component was also present but its intensity was substantially lower. It is concluded that while work hardening of the alloy during compression deformation at room temperature is affected mainly by non-shearable, coarse precipitates, the texture formation is controlled by both the shearable and non-shearable precipitates.

The texture development and γ-fibre recrystallisation texture formation mechanism of ferritic stainless steels under different rolling processes were investigated. It was shown that the surface texture development was absolutely different from the centre texture development. In conventional rolled band, strong α-fibre was formed at the centre layer and it was weakened after hot band annealing; after cold rolling, the centre texture was characterised by sharp α-fibre and weak γ-fibre with a peak at {111} , and non-uniform γ-fibre recrystallisation texture was developed. By contrast, in warm rolled band, the centre texture consisted of weakened α-fibre and sharpened γ-fibre, and {111} became the prominent component after hot band annealing. The α-fibre and γ-fibre with a peak at {111} were intensified at the centre texture after cold rolling, resulting in the formation of uniform γ-fibre recrystallisation texture. It was indicated that the formation mechanism of γ-fibre recrystallisati...

In order to elucidate the predominance of near-Goss grains after Strain-Induced Boundary Migration (SIBM) in electrical steel sheets, the microstructures of grains of orientations close to Goss, D-Cube, and {111}〈112〉 were observed by TEM after temper rolling of 5 % (which is the optimal strain for the development of a strong Goss-type texture) and 9 % reduction (selected to emphasize the differences between orientations and facilitate their analysis). After 5 % strain, the dislocation density seems to be the smallest in the Goss grains. After 9 % strain, this difference in dislocation density is still present but also accompanied by a difference in dislocation arrangement between the Goss grains and the others. These microstructural features are put in regards to some calculations of rotation rates of individual orientations and analyses of slip system activities performed with the Taylor model. The analysis of all these data allow us to establish a strong link between dislocation microstructure and stability of orientation and to conclude that this correlation may be responsible for the favored growth of the near-Goss grains by SIBM during annealing after 5 % temper rolling.

Data are presented on the x-ray line broadening distribution over the texture of cold-rolled Nb and Mo sheets. The method of generalized X-ray pole figures, which combine texture measurements with X-ray line profile analysis, is employed. The X-ray line broadening is considered as an indicator of residual deformation effects. It was revealed that these effects in cold-rolled BCC metals rise as the grain orientation shifts away from texture maxima towards texture minima. The intensity of X-ray reflections change during annealing at 200 – 500C and this change correlates with the line broadening. The recrystallization texture of BCC metals is dominated by orientations deflected from the peak maxima by 25 – 30 deg. These orientations in the deformed structure have relatively high stored energy. Their volume fraction is sufficient for them to be able to consume most of the deformed matrix.

Texture formation of AA5182 for compressive deformation with a range of temperatures from 673K to 823K and strain rates from 5.0×10-4to 5.0×10-2s-1is experimentally investigated by EBSD technique and X-ray diffraction. Fiber textures are observed in all deformation conditions. Stress regions are divided into a low stress region (10~55MPa) and a high stress region (above 55MPa) on the basis of the relationship between stress and grain size. In the low stress region, it is found that the main component of the fiber texture is {001}(compression plane). In this case, the pole density at {001} is increased with increasing temperature at the same stress level. It is concluded that development of {001} component is attributed to grain boundary migration. For the high stress region, the main component of the fiber texture is {011}. It is considered that the formation of {011} component is attributed to the slip deformation by {111} system.

Semi-processed nonoriented electrical steels are very attractive products whose magnetic properties are significantly improved through annealing treatment in customers plant. The improvement is due to strong Goss texture formation by strain induced boundary migration (SIBM). In order to the effect of temper rolling reduction on the strengthening of Goss texture, temper rolling reduction was changed in the range of 2% to 8%. The annealing times was changed from 10 minutes to 180 minutes. A mechanism of grain growth during SIBM is suggested from our experimental data. In the specimen temper-rolled by 2%, relatively strong {111} texture develops, whereas in the specimens temper-rolled by 4% through 8%, strong Goss texture develops as a result of SIBM during final annealing. It can be found from observed EBSD data that the Goss grains have the lowest stored energy in all temper-rolled specimens, which is confirmed by average image quality value in EBSD measurements. However, for the Goss grains to grow preferentially, stored energy difference between Goss grains and their neighboring grains may have to be higher than a certain critical value.

The effect of cold rolling reduction on shear band formation and crystal orientation within shear bands and annealing texture were investigated in Fe-3%Si {111} single crystals. Several types of shear bands were observed with different angles to rolling direction, dependent on rolling reduction. As for shear band formation, those with smaller angles were formed earlier and those with larger angles were formed later. Regarding crystal orientation along shear bands after rolling reduction, orientation distribution from the initial became large in accordance with reduction and even exceeded Goss orientation when rolling reduction became larger than 40%. After annealing, however, recrystallized grains along shear bands were mainly Goss grains regardless of reduction. The speculated reason for the dominance of Goss after annealing is that Goss subgrains with less density of dislocations were surrounded by largely deformed areas.

Interstitial free high strength steels (IFHS) are widely used in the automobile sector due to their high strength and excellent formability. However, these properties of IFHS steels are very much dependent on the processing parameters, like hot rolling, cold rolling and annealing. The composition and processing parameters influence the chemistry and morphology of the precipitates formed in these steels, which in turn control the texture and thus the deep-drawability. This review will briefly summarize the findings of the ongoing research in this area. An attempt will also be made to elucidate the correlation of precipitation behavior and texture formation (and thus formability) in these steels.

Features of the deformation process by cold radial forging of tube billets from Zr-1%Nb alloy were reconstructed on the basis of X-ray texture data. The cold radial forging intensifies grain fragmentation in the bulk of billet and increases significantly the latent hardening of potentially active slip systems, so that operation only of the single slip system becomes possible. As a result, in radially-forged billets unusual deformation and recrystallization textures arise, differing from usual textures of a-Zr by the mutual inversion of crystallographic axes, aligned along the axis of tube.

Experimental evidences of regular differences in the substructure condition of grains depending on their position within texture maxima are demonstrated. Analysis of generalized pole figures (GPF) for rolled metal materials shows that the strain hardening intensifies as an angular distance of grains from the texture maximum centre increases. The mechanisms of this phenomenon are considered using the concepts of the texture formation theory.

The classical definition of lattice rotation leads in some cases to different textures than the definition based on the preservation of orientations of selected sample directions and/or planes. For example, if classical {111} slip is taken into account for f.c.c. materials, the former approach enables to predict both copper and brass types of rolling texture, while classical approach predicts only the first one. The analysis of rolling texture formation is done for two types of lattice rotation in function of grain-matrix interaction parameter used in a deformation model. Predicted textures and correlation factors estimating the similarity of predicted and experimental textures are presented.

Single crystals of the alloy Ti-48%Ni-2%Fe, consisting of the phase B2, were rolled at 350°C with deformation degrees up to ~80% in 11 different initial orientations. Texture development in single crystals under rolling was analyzed to determine the active mechanisms of their plastic deformation. There are three stable initial orientations, which remain unchanged during rolling of Ti-Ni single crystals: {011}, {111} and {111}. It was shown, that Ti-Ni single crystals deform by means of combined action of slip in systems {011} and twinning in systems {114} and {118}. Variants of rolling texture formation in single crystals are very diverse and depend on their initial orientations and deformation degrees.

Formation of residual stresses and crystallographic textures during rolling have been studied using elasto-plastic deformation for polycrystalline material (Leffers-Wierzbanowski model). The rotation of grain crystal lattices is the basic mechanism of texture formation and anisotropic behavior of metals during plastic deformation. The classical definition of crystal lattice rotation leads in some cases to different texture predictions than the definition based on the orientation preservation of selected sample planes and/or directions (preservation condition). Also predicted residual stresses can be influenced by a choice of rotation definition. In the used deformation model of polycrystalline material, the intensity of grain-matrix interaction is described by the parameter L= aG, where G is shear modulus and a is elasto-plastic accommodation parameter. Model calculations have been done for different values of this parameter and for two definitions of lattice rotation. The predicted second order residual stresses and crystallographic textures for cold rolled ferrite steel are compared with experimental ones.

The precipitation behavior of inhibitors and their influence on final Goss texture formation in grain-oriented electrical steels produced by compact strip processing technology with a reheating temperature lower than 1200 °C were investigated under two distinct intermediate annealing methods: conventional intermediate recrystallization annealing and a new intermediate decarburizing and recrystallization annealing method without final decarburizing after the second cold rolling. The initiation of secondary recrystallization, the distributions of second phase particles, the final Goss texture, and the grain structure were observed. The new technology could maintain higher inhibitor densities because the deformed matrix could provide higher site densities for inhibitor nucleation before secondary recrystallization, resulting in a relatively higher inhibition effect of the second phase particles. The new technology could also compensate for the disadvantages of fewer inhibitors induced by fewer dissolved Mn and S elements in the matrix during lower reheating temperature for hot rolling. The final sheet produced after the secondary recrystallization annealing obtained stronger Goss texture, larger grain size, and better magnetic properties.

The friction stir welding (FSW) technique is widely accepted to be one of the most significant welding techniques to emerge in the last 20 years. Friction stir welding of Al-alloys is now commonplace and is covered in several recent reviews, including one in this journal. Consequently, the technique is currently being used for joining of these alloys in various industrial applications. Complementary to these developments has been a dramatic increase in research into joining of other alloys and systems by FSW. This field is very active, but less mature. Thus, the aim of this review article is to build on our understanding of the fundamentals, as applied to Al-alloys that laid out in the previous review in this journal, and to address the current state-of-the-art of FSW developing beyond Al-alloys, including Mg-alloys, Cu-alloys, steels, Ti-alloys and metal matrix composites, focusing particularly on microstructural aspects, including texture formation, and the resulting properties of these joints. ...

The crystallographic texture formation in low carbon steel during asymmetric rolling was studied experimentally and analysed numerically. Modelling of plastic deformation was done in two scales: in the macro-scale using the finite element method ( FEM) and in crystallographic scale using the polycrystalline deformation model (LW model). The stress distribution in the rolling gap was calculated using FEM and next these stresses were applied in LW model of polycrystalline plastic deformation. In general, the predicted textures agree very well with experimental ones.

The stretch formability of a rolled Mg-1.5Zn-0.1Ca alloy sheet was investigated at room temperature. The Mg alloy showed a large Erichsen value of 8.2. This is due to a reduction in intensity of basal plane texture and a spreading of the basal poles towards the transverse direction. It is suggested that solid solution of Ca atoms into Mg plays a critical role in the unique texture formation. Activation of non-basal slips by dilute Ca addition was hypothesized to be related to the unique texture formation.

Precipitation in IFHS steels affects texture formation during annealing, which in turn determines the formability. The single most important type of precipitates in IFHS steels is FeTiP. Precipitation of FeTiP leads to the decrement in the intensity of the favourable {111} texture, which causes a degradation of the formability properties. The batch annealed steels are particularly susceptible to this. Since formation of FeTiP as well as of the other types of precipitates in IFHS steels is dependent on steel composition and processing parameters, a detailed and systematic investigation is urgently needed to look into the various aspects of precipitation in IFHS steels. Proper scientific investigation is expected to provide necessary processing windows that will not allow formation of unwanted precipitates. This will help in maximising the strengthening effects of P, without any degradation of the deep drawability of the steels.

Two interstitial-free high-strength (IFHS) steels processed by continuous annealing, with and without Nb addition, have been studied. No major differences in precipitation behavior or texture formation in the two steels were observed. Nb addition does not improve the formability as such, but it appears to coarsen the carbide precipitates and reduces the volume fraction of the {1 1 1}〈1 1 0〉 texture component in the γ fiber.

Microstructure and texture formation behavior of a gold rod and fine wire which were produced by continuous casting process and drawing, respectively were investigated by means of optical micrographs, TEM images and X-ray pole figure. Well-developed unidirectional structure aligned to casting direction was found in 7 mm gold rod. Higher casting speed was found to be favor in developing the directional microstructure. In the sample with unidirectional microstructure developed in partial it is found that dislocation substructure with nano-size appeared to display a characteristic feature, while no dislocation substructure is seen in the sample with complete unidirectional microstructure. Interface stability between solid and liquid may be responsible for this difference in dislocation substructure. fiber component was observed to be well developed over the whole microstructure in unidirectional sample. With decreasing casting speed fiber component became weak. Two texture components consisting of fiber and fiber were seen in as-drawn samples. For the development of fiber texture component initial texture component plays a more significant role than subsequent annealing process. Annealing heat treatment would be effective way to control the formation of fiber component. On the basis of results obtained it is suggested that both the initial texture and final annealing are important in controlling the texture of gold bonding wire.

The present paper presents an overview of present and future tools which can be used by the steel manufacturer in order to control the texture of the finished sheet product. The major solidstate- transformation processes (phase transformation, plastic deformation and recrystallisation) playing a role during thermo-mechanical processing will be addressed. The physical mechanisms that give rise to the appearance of specific texture components will be discussed in detail. In addition to current state-of-the-art process technology the potential of innovative processes will be described such as accumulative roll bonding (ARB). The present paper will also pay attention to the particular role of surface textures as an additional degree of freedom allowing to control the sheet texture with the potential to enhance the {001} or {110} fibre textures for magnetic applications.

The effect of niobium (Nb) addition on recrystallization texture formation in cold-rolled low carbon steel sheets containing 2% manganese (Mn) was investigated. The microstructures of hot-bands were significantly refined by Nb addition, which led to the development of the cold-rolling texture in both the γ-fiber (//ND-fiber) and the α-fiber (//RD-fiber). Recrystallization was retarded by Nb addition, in particular, the growth of //ND grains was retarded. However, the γ-fiber and {112} grains developed during annealing even in the intercritical (α-γ) region. Consequently, the r-value increased as the content of Nb was increased due to the development of the intensity ratio of the //ND texture to the //ND texture, which is desirable for deep-drawable high strength steel sheets.

Influence of cold rolling total thickness reduction, annealing temperature and annealing time on the textures in powder metallurgic Ni-5at.%W substrate tapes have been quantitatively investigated with the EBSD (Electron Back-Scattered Diffraction) technique. A “copper” type-like texture consisting of {1 2 3}+{0 1 –1}+{1 –1 2} has been found in the as-rolled tapes. This texture was much intensive in the tape at 99% thickness reduction than in the tape at 87% thickness reduction. The 99% reduction tape showed a higher fraction and sharper cube texture than the 87% reduction tape after annealing treatment. In addition, annealing at 1000°C was much favourable for the cube texture formation than annealing at 950°C and resulted in a higher cube texture fraction.

Two interstitial free high strength (IFHS) steels of comparable chemistries but processed through batch annealing and continuous annealing routes have been studied. The near absence of FeTiP and presence of a large volume fraction of TiC are considered to be primarily responsible for the sharp {1 1 1} texture in the CA steel.

Cube textured Ni substrate were fabricated for YBCO coated conductors from the initial specimens prepared by powder metallurgy (P/M) and casting and the effects of annealing temperature and reduction ratio on texture formation and microstructural evolutio were evaluated. The initial specimens were rolled by 98.6% and 99.2% reduction ratio and then annealed in the temperature range of 600°C to 1200°C. The microstructure and texture were evaluated by optical microscopy and X-ray pole-figure analysis. We observed that microstructure of the initial specimen varied with preparation methods.Texture analysis indicated that a strong cube texture formed for substrate made by P/M, and the degree of texture did not significantly vary with annealing temperature of 600°C~1100°C. On the other hand, the texture of substrate made by casting was more dependent on the annealing temperature and twin texture ({221}) and several minor texture components started to form at 1000°C. In addition, the texture of substrate made by P/M was significantly dependent on the reduction ratio.

Thin copper films with grain sizes of 31 nm and 3.3 mm were processed by electrodeposition, and their mechanical properties were compared with those of a rolled copper film. The hardness and strength for the electrodeposited copper with a grain size of 3.3 mm were lower than those of the rolled copper with a grain size of 6.3 mm, however, the elongation to failure for the former was larger than that for the latter. Intense (111) texture formation was found for the rolled copper. Therefore, it is suggested that the difference in mechanical properties between the electrodeposited and rolled copper films are related to the texture formation. The electrodeposited copper with a grain size of 31 nm showed higher strength and larger elongation than the rolled copper. The very small grain size of 31 nm gave rise to the excellent mechanical properties. [doi:10.2320/matertrans.MAW200708]

Crystallographic textures of hydroxyapatite (HAp) and calcium-deficient hydroxyapatite (DAp) were controlled by hot forging. HAp, HAp-40 mass%DAp and DAp green bodies prepared by a colloidal process were hot-forged at 1273 or 1473 K, after which the c-axes of HAp and DAp with a hexagonal-based structure tended to be aligned perpendicular to the forging direction. Crystal rotation of the rod-shaped HAp and DAp during hot forging led to the texture formation, and the tendency of the texture formation enhanced with increasing forging pressure. Hot-forged HAp samples exhibited stronger texture at 1273 K than 1473 K while the texture of HAp-40 mass%DAp and DAp samples was more strongly concentrated at 1473 K. Aspect ratios of HAp and DAp, which might depend on forging temperature, was thought to strongly affect the formation of the crystallographic texture.

Five Mg–Li–Zn alloys namely Mg-11%Li-1%Zn, Mg-9%Li-1%Zn, Mg-9%Li-1%Zn-0.2%Mn, Mg-9%Li-1%Zn-1%Al-0.2%Mn, and Mg-9%Li-3%Al-1%Zn-0.2%Mn were prepared. These alloys have been processed by equal channel angular extrusion (ECAE), and the subsequent mechanical properties and microstructures were studied. After ECAE process, the room temperature strength was significantly enhanced at a modest cost of elongation reduction. From the results of five Mg–Li–Zn alloys as processed by ECAE, Mg–9Li–1Zn alloy has the greatest increase in tensile strength and the least decrease in elongation. The high temperature superplasticity was demonstrated. However, the testing conditions were selective. As for texture formation, the weak to medium extent was produced after four passes of ECAE process at 373 and 423 K. The density and elastic modulus properties of these alloys were analyzed, and showed the highest specific value as compared with other popular alloys, not to mention plastics.

Effects of grain size and texture on the damping properties in the Cu–Al–Mn-based shape memory alloys were investigated mainly by dynamic mechanical spectrometry. Dynamic damping tan ϕ obtained from the martensite single-phase specimens increases with increasing relative grain size d / t , where d and t indicate the grain size and the specimen sheet thickness, respectively. Moreover, tan ϕ increases due to the development of texture formation, a textured sheet with d / t = 1.34 shows a large tan ϕ of about 0.09 in the martensite phase. Damping alloys with tensile strength over 850 MPa and tan ϕ of about 0.04 can be obtained by controlling the relative grain size and texture.

Precipitation and texture formation in two cold rolled and batch-annealed interstitial-free high strength steels have been studied. TiN, Fe(Ti + Nb)P and TiC were the main precipitates observed. A perceptibly higher population of Fe(Ti + Nb)P precipitates in the steel containing a higher amount of P is considered to be primarily responsible for the less intense {1 1 1} texture.

The influence of a heating rate up to 1000 � C/s on recrystallization behavior and texture formation of an extralow carbon steel sheet was investigated. To discuss the experimental results of this investigation, a mathematical model for predicting recrystallization behavior was developed. An analysis using the model shows that the heating rate influences the apparent thermal activation energy of recrystallization. At a higher heating rate, C dissolved from cementite and AlN precipitated during heating decreases and as a consequence the apparent thermal activation energy is lower. This can also be a valid explanation for the fact that recrystallization of a steel sheet coiled at low temperature is retarded. The main orientations of the recrystallization texture are weakened if the heating rate is increased. This tendency has already been observed at the initial stage of recrystallization. If the specimen is heated slowly up to the initial stage of recrystallization, the decrease in the intensity of the main orientations is reduced even though the heating rate subsequently increases. This result indicates that, concerning formation of the recrystallization texture, the heating rate mainly influences the nucleation process. [doi:10.2320/matertrans.47.1769]