Showing papers on "Texture (crystalline) published in 1985"
TL;DR: In this article, a method for describing the anisotropy of textured cubic polycrystals in terms of the ellipsoidal yield surfaces originally proposed by Hill is demonstrated.
195 citations
TL;DR: In this article, the yields of polycrystals with a random grain orientation distribution were investigated for a family of grains with particular orientations, submitted to a shear strain and the results were extended to more general cases and compared with experiments.
128 citations
121 citations
TL;DR: In this article, the alignment direction corresponds to a channeling direction for the incident ions between (110) planes, for which a low sputtering yield is expected, and the degree of alignment is measured as a function of ion/atom arrival rate ratio up to 1.3 Ar+ ions per Nb film atom.
Abstract: Glancing angle ion bombardment during thin‐film deposition is shown to have a pronounced alignment effect on crystallographic orientation. Restricted fiber texture is achieved in Nb films deposited at room temperature onto amorphous silica substrates by Ar ion beam sputtering, with simultaneous bombardment by 200 eV Ar+ ions at 20° from glancing angle. The alignment direction corresponds to a channeling direction for the incident ions between (110) planes, for which a low sputtering yield is expected. The degree of alignment is measured as a function of ion/atom arrival rate ratio up to 1.3 Ar+ ions per Nb film atom, and is shown to increase monotonically with the fraction resputtered.
117 citations
TL;DR: In this paper, the scattering coefficients and the phase and group velocities of plane compressional and shear waves in textured polycrystals were derived for cubic symmetry with rolling texture in second-order perturbation theory.
Abstract: The theory of ultrasonic propagation in polycrystals with independent and uniformly distributed orientations of the grains presented in previous papers [J. Acoust. Soc. Am. 72, 1021–1031 (1982); 73, 1160–1163 (1983)] is generalized to calculate the scattering coefficients and the phase and group velocities of plane compressional and shear waves in textured polycrystals. The calculation was done for plane waves in polycrystals of cubic symmetry with rolling texture in second‐order perturbation theory using the assumption that the changes in the material constants from grain to grain are small. In the limit texture equal to zero the analytical results are exactly the same as those for untextured polycrystals previously presented. Numerical calculations are carried out for some examples.
61 citations
TL;DR: In this paper, the effects of orientational texture on the low-field susceptibility of a fine particle system in a solid environment is described, where the texture is produced by cooling the system slowly through its freezing point in a field H.
58 citations
55 citations
TL;DR: The dc reactive magnetron sputtering process yields stoichiometric NbN films with superconducting transition temperature T(c) as high as 15.7 K on substrates as varied as glass, glazed ceramic, fused quartz, and sapphire as discussed by the authors.
Abstract: The dc reactive magnetron sputtering process yields stoichiometric NbN films with superconducting transition temperature T(c) as high as 15.7 K on substrates as varied as glass, glazed ceramic, fused quartz, and sapphire. These films posses fcc (B1) structure and (111) texture. The most dominant factors governing the formation of the transition metal nitrides are the relative metal and nitrogen fluxes incident on the substrate and the background argon pressure (which dictates the overall reactive sites and residence times for nitrogen).
52 citations
43 citations
TL;DR: In this article, the authors derived analytic expressions based on a self-consistent deformation model to relate irradiation deformation of polycrystals to that of a single crystal, in terms of the specimen crystallographic texture, for both the low and high neutron-fluence regimes.
40 citations
TL;DR: In this article, the crystal texture and microstructure of sputtered Cr thin films were investigated using a dc magnetron, and the correlation between the physical and crystal structure and the texture development was discussed.
Abstract: The crystal texture and microstructure of sputtered Cr thin films deposited on various substrates using a dc magnetron were investigated. The characterization of Cr films was carried out by an x‐ray technique for texture, scanning electron microscopy and transmission electron microscopy for structure and morphology, and scanning Auger microprobe for chemical distribution of sputtered films. The sputtered Cr thin films were found to have very strong [110] preferred orientation which was independent of the substrate. Very straight columnar structures were observed with domed tops which increased in width with deposition thickness. The columnar width near the surface was found to range from 300 to 2000 A. The crystal grain size also increased with film thickness. The correlation between the physical and crystal structure and the texture development is discussed.
TL;DR: In this paper, the authors derived activation energy and area of Zircaloy-4 and showed that the climb of edge dislocations is the rate-controlling mechanism for creep in Zirca-aloy, and derived a single relationship which correlates the temperature and stress dependence of primary creep behavior over the range of experimental investigation.
TL;DR: The crystal orientation of silver films evaporated onto glass in a vacuum of better than 1.33 × 10−3 Pa was studied as a function of the film thickness in the range 0.1 −10 μm by means of the X-ray texture goniometer technique as mentioned in this paper.
Patent•
02 Oct 1985TL;DR: In this paper, a polyolefin hollow fiber membrane is described, which is composed of an annular cross section of substantial circle 150 to 300 μm inside diameter and 10 to 150 μm in wall thickness.
Abstract: A porous hollow fiber membrane, comprising a polyolefin hollow fiber membrane of an annular cross section of substantial circle 150 to 300 μm in inside diameter and 10 to 150 μm in wall thickness, said hollow fiber membrane forming on the inner wall side thereof a tight layer of intimately bound fine polyolefin particles and on the outer wall side thereof a porous texture of fine polyolefin particles bound in chains and containing fine pores extended continuously form said inner wall side to said outer wall side.
Patent•
05 Dec 1985TL;DR: In this article, the erasure of optical information can be performed upon an alloy film capable of forming two stable crystalline states differing in crystal texture and optical characteristics, by irradiating the film with optical energies under different conditions.
Abstract: Recording and erasure of optical information can be performed upon an alloy film capable of forming two stable crystalline states differing in crystal texture and optical characteristics, by irradiating the film with optical energies under different conditions. Alloys comprising two or more elements capable of forming a eutectic mixture may be used to form the alloy film.
TL;DR: In this article, a model for the development of the basic longitudinal texture is proposed involving a meniscus instability of the propagating crack front, which gives rise to a series of fingers protruding into the bulk resin ahead of the nominal crack front.
TL;DR: The columnar structure and texture of obliquely deposited iron films prepared at various pressures were investigated in this paper, and it was concluded that the movement of adatoms as a result of their momenta determines the character of the columnar texture and that the scattering effect of residual gases on the vapour atoms becomes appreciable above 1 x 10 -3 Torr.
TL;DR: In this paper, a simple method was presented for calculating the plastic strain ratio from crystallographic texture based on ideal sheet textures, and the R values for several f c c and b c c metals were calculated as a function of angle to the rolling direction using this method.
Abstract: A simple method is presented for calculating the plastic strain ratio from crystallographic texture based on ideal sheet textures. The R values for several f c c and b c c metals were calculated as a function of angle to the rolling direction using this method. The agreement between calculated and measured R values was satisfactory.
TL;DR: In this paper, the free surface of the amorphous Fe91Zr9 ribbon has a strong texture with its (100) plane parallel to the ribbon surface, which can be easily removed by polishing lightly with emery paper.
Abstract: A fairly thin crystalline layer was proved to be formed on the free surface of amorphous Fe-rich Fe-Zr alloys during the melt-spinning process. This crystalline surface layer can be easily removed by polishing lightly with emery paper. X-ray diffraction results for melt-spun amorphous Fe100-xZrx alloys showed that the crystalline surface layer consists of BCC Fe for 8
TL;DR: In this paper, the ESR spectra of the as-produced films exhibit two signals, one at g about 4.2 and the other at g 2.2, and a ferromagnetic signal was detected by heat-treating the samples in hydrogen atmosphere between 500 and 800 °C.
Abstract: Iron oxide films on borosilicate glasses were produced with the sol‐gel method. The ESR spectra of the as‐produced films exhibit two signals, one at g about 4.2 and the other at g about 2. A ferromagnetic signal was detected by heat‐treating the samples in hydrogen atmosphere between 500 and 800 °C. Angular variation of the ferromagnetic resonance signals revealed an internal field parallel to the plane of the films. The internal field was about 3500 G in the film heat treated at 620 °C for 120 min. Scanning electron microscopy was also used for detailed surface characterization. Before treatments the film is characterized by a fine texture and a few voids whose dimensions are about 5×15 μ. After treatments the film contains particles about 15 μ in size.
TL;DR: In this paper, a stacked lamellar texture was found to arise from crack fingers due to a meniscus instability mechanism interacting with a reorienting stress field in an E-glass/epoxy composite.
Abstract: A fracture surface texture, which has been variously termed as “lacerations”, “hackles” or “serrations”, is often observed on the matrix surface of fibre composites, most often in resin-rich regions. This texture, referred to here as a “stacked lamellar texture” to emphasize its plate-like nature, was studied in an E-glass/epoxy composite. Scanning electron fractographs of these materials suggest that the stacked lamellar texture arises from crack fingers due to a meniscus instability mechanism interacting with a reorienting stress field.
TL;DR: In this paper, the magnetic properties of multilayered Co/Mn films with layer thickness ranging from 7-70 A have been studied and the results imply the existence of α-Co (002)/α-Mn (330) stacking texture.
Abstract: Magnetic properties of multilayered Co/Mn films with layer thickness ranging from 7–70 A have been studied. The films were prepared by alternately depositing Co and Mn layers in an ultrahigh vacuum (UHV) evaporator. X‐ray θ‐2θ scans with Cu‐Kα radiation showed a main diffraction peak around 2θ=44° for all films and satellite peaks for some of them. The data imply the existence of α‐Co (002)/α‐Mn (330) stacking texture. Ferromagnetic resonance (FMR) study and vibrating‐sample magnetometer (VSM) measurement show that the magnetization of Co layers decreases with decreasing Co thickness as if 1.5 atomic layers lost their magnetic moments at the interface. FMR spectra of the films show a peculiar temperature dependence in that the perpendicular resonance field starts to decrease below a certain temperature. The results are discussed.
TL;DR: In this paper, changes in microstructure and texture during superplastic deformation of strongly textured Ti-6Al-4V bar have been determined in order to establish the cause of stress and strain anisotropy.
Abstract: Changes in microstructure and texture during superplastic deformation of strongly textured Ti-6Al-4V bar have been determined in order to establish the cause of stress and strain anisotropy. The effect of strain on the microstructure of the alloy was to cause a progressive break-up, due to grain-boundary sliding, of an initially directional microstructure containing contiguousα-phase. The texture of theα-phase, however, changed very little with superplastic strain but that of theβ-phase was randomized. Shape changes predicted by permitted deformation modes in theα-phase did not correlate with the observed shape changes, whereas the observed anisotropy could be explained by the break-up of the contiguousα-phase. A model to account for this anisotropy is described briefly, together with a typical microstructure which should exhibit isotropic superplastic deformation.
TL;DR: In this article, the results of three different types of experiment are discussed: 1. Density, flexural strength and fracture toughness data at room temperature for different materials after post-hipping.
TL;DR: In this paper, the surface textures of the grains observed by scanning electron microscope were classified into texture groups I-IV, in the order from a simple feature through increasing undulations to a texture with cavities.
TL;DR: In this article, cylindrical specimens machined from Zr-2.5 wt % Nb and Excel alloy pressure tubes were tested at constant true strain rates of 10−4 and 10−1s−1 in compression over the temperature range 295-1200 K. The direction dependence of the flow stress is interpreted in terms of the crystallographic texture of the pressure tubes.
TL;DR: In this paper, the effect of magnetic and non-magnetic materials on the superconducting proximity effect in a superlattice geometry was analyzed using a variety of structural and physical techniques.
TL;DR: In this paper, the effect of nitrogen in the sputtering gas on the crystal texture and microstructure of 1 μ thick 81/19 Ni-Fe films sputter deposited on silica glass and silicon.
Abstract: This work reports the effect of nitrogen in the sputtering gas on the crystal texture and microstructure of 1 μ thick 81/19 Ni–Fe films sputter deposited on silica glass and silicon. X‐ray diffraction, transmission electron microscopy, and scanning auger microprobe analysis have been used to characterize films’ properties. The films show (111) and (002) crystals orientations. Upon increasing the nitrogen content of the sputtering gas, the amount of (111) crystal texture decreases; whereas the amount of (002) crystal texture shows a maxima at about 0.1% nitrogen. The microstructural analysis of films shows that the presence of nitrogen in the sputtering gas promotes fine grain size. The mechanism of crystal texture development with an increase in the amount of nitrogen in the sputtering gas is discussed.
01 Sep 1985
TL;DR: In this article, the magnetic properties of textured fine particle systems consisting of cobalt particles in a solid environment were measured and it was found that the texture of the irreversible particles is reflected in the remanence of the system while that of the reversible particles is evident in the slope of the magnetisation curve in small fields.