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In this paper, an experimental investigation of the machinability of Titanium grade 23 has been carried out using hybrid micro-textures on the cutting tool. The different types of micro-textures have been fabricated on the rake surface as well as on the flank surface of the cutting tool. The performance of textured tools with the presence of a chip breaker has been investigated. The selected patterns were vertical grooved rake face (VT-R), diagonal grooved rake face (DT-R), vertical grooved flank face (VT-F) and hybrid textured tools namely, vertical rake and flank (V+V), diagonal rake and vertical flank (D+V). A comparative study has been carried out to acknowledge the performance of textured tools while dry turning Titanium Grade 23 alloy. The machinability has been made to acknowledge the performance of textured tools with the variation of machining time in case of dry turning operation. The machinability criteria are investigated based on cutting forces, cutting temperature and tool wear mechanisms involved while machining. The performance of the cutting tool with DT-R and VT-F micro-texture is observed to be better in comparison to others. Innovative applications of micro-textured tools are for dry green machining without any environmental hazards and proper chip-flow control.

Out of the 15 3 × 3 neutrino mass matrices with two texture zeros, seven are compatible with the neutrino oscillation data. While two of them correspond to hierarchical neutrino masses and 1 to an inverted hierarchy, the remaining four correspond to degenerate masses. Moreover only the first three of the seven mass matrices are compatible with the maximal mixing angle of atmospheric neutrino and hence favored by data. We give compact expressions for mass matrices in terms of mass eigenvalues and study phenomenological implications for the seven cases. Similarity of the textures of the neutrino, charged-lepton mass matrices with those of quark mass matrices is also discussed.

In this work, effect of thickness of the liquid crystalline layer on the morphologic, thermotropic and thermodynamical properties of the nematic–isotropic liquid and isotropic liquid–nematic phase transitions in Shiff based liquid crystals has been investigated.

The shift of temperatures of the nematic–isotropic liquid and isotropic liquid–nematic phase transitions to the lower temperatures and the widening of linear and temperature widths of the heterophase regions of these phase transitions by the increase in the thickness of liquid crystalline layer have been found.

The effect of thickness of liquid crystalline layer on morphologic, thermotropic and thermodynamical properties of liquid crystals under investigations is connected with change of interaction energy between liquid crystalline molecules and reference surfaces.

Fe-3.2%Si steel strips were produced using vertical type twin casting process, and the changes of microstructure and texture trough thickness direction were analyzed. The equiaxed grains of approximately 44.6µm were observed in the center layer, the great mass of columnar dendrite was formed near the surface, and the dendrite truck mainly developed in the transverse direction with respect to the casting direction of about 45° or less. From the subsurface to the center, the volume fraction of the Goss texture (110)[001] gradually decreases. The Goss {110} <001> components at the surface are two times those at the center layer, the {001} <100> components are three times those at the center layer, and the overall texture components are similar to that of the hot-rolled oriented silicon steel strip. The minor α texture could be found from the φ₂=45° sections of ODF, and there is no remarkable composition segregation of Si element in the thickness direction of thin strip.

The physical, mechanical properties and formability of sheet metal depend on preferred crystallographic orientations (texture). In this research work, we investigated texture development and formability of AA 3003 aluminum alloy sheets after asymmetry rolling and subsequent heat treatment. After asymmetry rolling, the specimens showed fine grain size. We also investigated the change of the plastic strain ratios after asymmetry rolling and subsequent heat-treating condition. The plastic strain ratios of asymmetrically rolled and subsequent heat treated samples are 1.5 times higher than the initial AA 3003 Al alloy sheets. These could be attributed to the formation of ND//<111> texture component through asymmetry rolling in Al sheet.

In this study, the FEM material model based on the crystal plasticity is introduced for the numerical simulation of deep drawing process of A5052 aluminum alloy sheet. For calculating the deformation and stress in a crystal of aluminum alloy sheet, Taylor's model is employed. To find the texture evolution, the crystallographic orientation is updated by computing the crystal lattice rotation. In order to verify the crystal plasticity-based FEM material model, the strain distribution and the draw-in amount are compared with experimental measurements. The crystal FEM strains agree well with measured strains. The comparison of draw-in amount shows less 1.96% discrepancy. Texture evolution depends on the initial texture.

In this study, strong {0002} textured (or strong ND//<0002> textured) AZ31 Mg alloy sheets were prepared. These AZ31 Mg alloy sheets were cut along the angles of 0, 12.5, 25, 30 and 37.5 degrees to the rolling direction or {0002} texture. Prepared samples with different angles to the rolling direction were rolled at room temperature and after subsequent heat treatment, the bendability, ultimate tensile stress, elongation and texture are investigated using the 3-points bending tester, tensile tester and x-ray diffractometer, respectively. The specimen having along the angles of 0 degree to the rolling direction shows the highest load and 45 degrees specimen shows the highest displacement among any other specimens in the bending test. The specimen having along the angles of 12.5 and 25 degrees to the rolling direction shows highest elongation and of 0 degree specimen shows the highest ultimate tensile stress among any other specimens after cold rolling and subsequent heat treatment at 150°C for 30 minutes in bending test.

Formability is very important parameter of magnesium alloy sheets and it would be related to the texture of sheet metals. In this study, magnesium alloy sheets with strong {0002} texture were cut along the angles of 0, 12.5, 25 and 37.5 degrees to rolling direction (RD). Prepared samples were rolled at room temperature condition. Cold rolled AZ31 magnesium alloy sheets along the angles of 0, 12.5, 25, 37.5 and 45 degrees to rolling direction were investigated microstructure and texture with optical microscopy and x-ray diffractometer, respectively.

The microstructure, pole figure and r-value of the frictionally rolled and subsequently heat treated AA 5052 Al sheets were investigated by optical microscopy, x-ray diffractometer and tensile tester, respectively. Frictionally rolled AA 5052 Al specimens showed a fine grain size. After subsequently heat treated specimens, the ND//<111> texture component was increased. The r-values of the frictionally rolled and subsequently heat treated Al alloy sheets were about two times higher than those of the original Al sheets. These could be related to the formation of ND//<111> texture components through frictional rolling in and subsequent heat treatment of AA 5052 Al sheet.

In order to improve the deep drawability of aluminum and aluminum alloy sheets, it is desirable to increase the ND//<111> component in their textures. The ND//<111> component is known to develop in shear-deformed fcc alloy sheets. The equal-channel angular pressing (ECAP) is a process in which materials undergo approximately simple shear deformation. The deformation texture of ECAPed strips can change depending on process variables such as the texture of starting strips, the oblique angle, the number of pressing passes, and the shear direction. The deformation and deformation texture have been analyzed.

Magnesium alloys still have a lot of technical challenges to be solved for more applications. There have been many research activities to enhance formability of magnesium alloys. One is to design new alloy composition having better formability. Also, low formability of wrought alloys can be improved by optimizing the processing variables. In the present study, effect of process variables such as forging temperature and forging speed were investigated to forgeability of three different magnesium alloys such as AZ31, AZ61 and ZK60. To understand the effect of process variables more specifically, both numerical and experimental works have been carried out on the model which contains both upsetting and extrusion geometries. Forgeability of magnesium alloys was found to depend more on the forging speed rather than temperature. Forged sample showed a significant activity of twinning, which was found to be closely related with flow uniformity.

Backward tube spinning experiment of BT20 (Ti-6Al-2Zr-1Mo-1V) alloy was carried out with an aim to examine texture evolution of titanium alloy in spinning process. The initial texture and the spinning texture were investigated by X-ray diffraction, and deformation history of a single-pass spinning was analyzed using finite element method. Tilt basal texture occurs when thickness reduction reaches a medium level (~ 49% for the outer surface and ~ 58% for the inner surface in the present study) and that further deformation promotes the formation of central basal texture. During early several passes basal texture in the outer surface develops more rapidly and intensely than that in the inner surface due to much larger deformation. However, the maximum intensity of texture in the inner surface reaches a higher level in subsequent passes for the following two reasons: (1) the discrepancy between equivalent deformation in the internal layer and that in the external layer reduces with increasing deformation; (2) material in the inner surface undergoes much smaller transverse shear deformation. Spinning texture is characterized by its asymmetry, which results from asymmetric spinning deformation investigated by analyzing deformation histories of material particles located in the inner and outer surface.

The inhomogeneity on texture, microstructure and magnetic properties of hot deformed (HD) disc shape R₂Fe₁₄B-typed magnets along radial and axial directions has been investigated. HD disc shape NdFeB magnet exhibits inhomogeneous texture, grain morphologies and magnetic properties not only along the radial direction but also along the axial direction. Higher magnetic properties can be found in the middle part of the HD magnet, due to the existence of larger volume fraction of plate-like Nd₂Fe₁₄B grains and the well c-axis alignment parallel to the pressing direction. In addition, particle-like and coarser grains are easily found not only in the bottom but also in the edge of the HD magnet, which may degrade the magnetic performance of the samples cut from those parts. Owing to the inhomogeneity of (00L) texture and grain morphologies along axial and radial directions, the optimal magnetic properties of B_r = 12.7 kG, H_ci = 5.1 kOe and (BH)_max = 39 MGOe can be obtained only in the middle sample of HD magnet with slight polishing the top and bottom surfaces.

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

Titanium (Ti) thin films with (002) or (100) texture are favored for many applications. In this paper, Ti thin films were prepared by high-power pulsed magnetron sputtering, and the texture of Ti thin films was successfully tailored by adjusting the pulse width, substrate bias and magnetic field strength. It is found that the peak power and average power of the Ti target are increased by increasing sputtering pulse width and decreasing magnetic field strength, which raise the Ti plasma flux and ion/atom ratio of Ti ions in front of the substrate simultaneously. Ti thin films with a highly (002) out-of-plane texture can be obtained with higher pulse width and lower magnetic field strength. The Ti thin films with highly (100) out-of-plane texture can be achieved with shorter pulse width, lower magnetic field strength and substrate bias.

Existing proposals for the crystal structure of the high temperature superconducting Bi₂Sr₂Ca₂Cu₃O_7-x (Bi2223) phase have been reviewed. For the purpose of automated orientation determination in the scanning electron microscope using electron backscatter pattern (EBSP) analysis, a new crystal structure is proposed, where the unit cell is assumed to be tetragonal with P4/mmm point-group symmetry. Simulated EBSP images corresponding to the various unit cells exhibit significant differences, confirming the importance of choosing the correct unit-cell information. The suitability of various choices of the unit cell for automated orientation determination using EBSP analysis has been investigated using experimental data. The newly proposed unit cell is superior to the other unit cells for each of the criteria used to assess the indexing ability.

Epitaxial CeO₂ seed layer and La₂Zr₂O₇ (LZO) buffer layers were deposited on biaxially-textured Ni–5 at.% W (NiW) tape substrate by liquid-phase polymer assisted nanoparticles deposition (PAND) method. LZO layers deposited by PAND have consistently shown tilting of the $c$-axis toward the direction of the sample’s surface normal. A new approach increasing the sharpening of the buffer texture by magnetic structural processing (MSP) of buffer layers was tested. The LZO layers, deposited on the seed and buffer layers after MSP, have dense and smooth surface structure, and more importantly, significantly improved out-of-plane texture, compared with the LZO layers that were deposited on a layer without MSP. Transmission electron microscopy study confirmed the $c$-axis tilting of CeO₂ and LZO layers and revealed the absence of interfaces between LZO layers which have been grown on the layers after MSP. There are very small (2–4 nm) gated pores in the single-crystal structure of LZO layers that are not typical for structure of LZO layers obtained by liquid-phase methods. Thus the LZO buffer layers can serve as an effective metal-ion diffusion barrier.

Asymmetric rolling (ASR) is distinguished from conventional symmetric rolling (SR) process as the mismatched rolling speeds of two rolls introduce additional shear deformation to the rolled strips. Friction between the rolls and strip plays an important role in the formation of shear during ASR, which further impacts the microstructures of metallic strips. In this study, finite element (FE) simulations are used to probe the effects of friction in ASR of magnesium (Mg) alloy strips with varied roll speed ratios. The results on shear deformation distributions through the thickness of the strips reveal that the increase of friction coefficient or roll speed ratio induces greater shear deformation simultaneously. It is also found that the roll speed ratio can only promote the shear formation up to a threshold value which is dictated by the friction coefficient, further increasing the mismatch of the roll speeds provides negligible improvement on the plastic deformation of the strips. Experimentally, Mg–1Gd alloy strips are processed by SR and ASR, followed by electropulse treatment (EPT) to induce static recrystallization (SRX). The predictions of the numerical models are verified via EBSD and XRD observations on the grain refinement and texture weakening in Mg–1Gd alloy, which are the direct microstructure consequences of plastic deformations during rolling. At the roll speed ratio of 1.67, the alloy shows a weakened basal texture with an average grain size of 6.0$\mu$m after SRX. Further increasing the roll speed ratio to 5, however, does not enhance the grain refinement or texture weakening significantly.

An object-based image retrieval method is addressed in this paper. For that purpose, a new image segmentation algorithm and image comparing method between segmented objects are proposed. For image segmentation, color and textural features are extracted from each pixel in the image and these features are used as inputs into VQ (Vector Quantization) clustering method, which yields homogeneous objects in terms of color and texture. In this procedure, colors are quantized into a few dominant colors for simple representation and efficient retrieval. In the retrieval case, two comparing schemes are proposed. Comparisons between one query object and multi-objects of a database image and comparisons between multi-query objects and multi-objects of a database image are proposed. For fast retrieval, dominant object colors are key-indexed into the database.

An approach to integrating the global and local kernel-based automated analysis of vocal fold images aiming to categorize laryngeal diseases is presented in this paper. The problem is treated as an image analysis and recognition task. A committee of support vector machines is employed for performing the categorization of vocal fold images into healthy, diffuse and nodular classes. Analysis of image color distribution, Gabor filtering, cooccurrence matrices, analysis of color edges, image segmentation into homogeneous regions from the image color, texture and geometry view point, analysis of the soft membership of the regions in the decision classes, the kernel principal components based feature extraction are the techniques employed for the global and local analysis of laryngeal images. Bearing in mind the high similarity of the decision classes, the correct classification rate of over 94% obtained when testing the system on 785 vocal fold images is rather encouraging.