An X-ray investigation of slowly cooled copper-nickel-aluminium alloys

1938 ◽  
Vol 167 (930) ◽  
pp. 421-438 ◽  
Keyword(s):  
Aluminium Alloys ◽  
Equilibrium Diagram ◽  
Pure Copper ◽  
Cubic Phase ◽  
X Rays ◽  
X Ray ◽  
Recent Letter ◽  
Copper Nickel ◽  
Phase Fields ◽  
The Face

In a recent letter to Nature (Bradley, Goldschmidt, Lipson and Taylor 1937) it was shown that even a complicated ternary equilibrium diagram might be rapidly and efficiently investigated by means of X-rays. A diagram for the copper-nickel-aluminium system worked out by the authors of the present paper was given as as example. Since then we have completed the investigation, solving some problems which had been left in abeyance. The whole of the ternary system has now been completely explored for slowly cooled alloys. The copper-nickel-aluminium system has previously been inverstigated by a number of workers. Austin and Murphy (1923) determined the liquidus and part of the solidus, exploring the whole system at high temperatures, but without locating the phase fields. Bingham and Haughton diagram. In a careful thermal investigation they found many complicated transformations. Gridnew and Kurdjumow (1936) have investigated the effect of adding nickel to the copper-rich copper-aluminium alloys. Recently Alexander and Hanson (1937) measured the hardness and electrical conductivity of alloys lying on the boundary of the face-centred cubic phase in the neighbourhood of pure copper. From these results they determined the change of solid solubility with temperature.

scholarly journals Face-on SS 433 Stars as a Possible New Type of Extragalactic X-Ray Sources

2001 ◽  
Vol 205 ◽  
pp. 268-269 ◽  
Author(s):  
S. Fabrika ◽  
A. Mescheryakov
Keyword(s):  
X Rays ◽  
Relativistic Jets ◽  
Expected Frequency ◽  
X Ray ◽  
Ss 433 ◽  
Sky Survey ◽  
Supercritical Accretion ◽  
The Face ◽  
New Type ◽  
Positive Correlations

The object SS433 is a well-known source of relativistic jets, which are formed in supercritical accretion disk. It is very probable that the disk has polar channels and their radiation is collimated (the photo-cones). A face-on SS433 object can appear as ultra-bright and highly variable X-ray source, Lx ˜ 1040 − 1042 erg/s. We discuss the properties of these hypothetical objects and their frequency expected in galaxies. We describe a search for such objects using the ROSAT All Sky Survey and RC3 catalog of galaxies. Among the total 418 positive correlations we find that 142 sources in S and Irr galaxies are unknown as AGNs. Nuclear sources among them still contain many AGNs. Non-nuclear (offset) sources are rather hard, their X-ray luminosities are 1039 − 1041 erg/s. Their observed frequency is about 4–5% per galaxy, that is in agreement with expected frequency of the face-on SS 433 stars. The only way to recognize such stars is their expected violent variability in X rays.

scholarly journals X-ray analysis of the crystal-structure of rutile and cassiterite

1917 ◽  
Vol 93 (653) ◽  
pp. 418-427 ◽  
Keyword(s):  
Crystal Structure ◽  
Royal Society ◽  
Incident Beam ◽  
X Rays ◽  
Narrow Beam ◽  
X Ray ◽  
Axis Of Rotation ◽  
Ordinary Light ◽  
The Face ◽  
Ionisation Chamber

The present paper deals with the results obtained in the investigation of the atomic structure of rutile and cassiterite by the X-ray spectrometer. A detailed account of the method has been given by Prof. Bragg and his son, W. L. Bragg, in a series of papers communicated to the Royal Society. It consists essentially in allowing a narrow beam of monochromatic X-rays—in this case the rhodium rays—to fall on the face of the crystals, mounted on a spectrometer table, the axis of rotation of which passes through the face of the crystal. The beam is “reflected” by the atom planes parallel to this face, and thence passes into an ionisation chamber, containing methyl bromide in order to increase the ionisation current. The setting of crystal and chamber with regard to the incident beam corresponds to that for which ordinary light is reflected.

A Spherically Bent Crystal X-Ray Specteometer with Variable Curvature

1973 ◽  
Vol 17 ◽  
pp. 521-530
Author(s):  
Donald L. Parker
Keyword(s):  
Signal To Noise Ratio ◽  
Three Dimensional ◽  
High Signal ◽  
X Rays ◽  
X Ray ◽  
Bent Crystal ◽  
Variable Curvature ◽  
The Face ◽  
Low Levels ◽  
And Performance

AbstractThe design and performance of a spherically bent crystal x-ray spectrometer with variable curvature are given. A thin crystal with the diffracting planes parallel to the face is mounted on a vacuum chuck consisting of an O-ring in a brass mounting. A controlled partial vacuum is applied behind the crystal to cause spherical deformation of the lattice. Thus, rays from a point source on the focusing circle are diffracted to a line image also on the focusing circle. The differential pressure is automatically varied such that the source-to-crystal and crystal-to-image distances are equal and constant for all Bragg angles and hence the simple θ-2θ motion of a one flat crystal spectrometer is used.The data are accumulated by a scanning proportional counter tube placed behind a vertical slit (perpendicular to the scattering plane) located at the image line. The fixed chord length is 22 cm and the instrument is designed to scan from zero up to 120° 2θ. Crystals are easily interchanged and the automatic vacuum regulator has sufficient flexibility to allow tailoring the spherical bending to crystals of materials of various thicknesses. The resolution is easily adjusted by either the size of the x-ray source or the width of the detector slit. The performance of the spectrometer has been evaluated by characteristic x-rays produced by various samples placed in a demountable x-ray tube. The main advantages of this three-dimensional focusing instrument are the very high signal-to-noise ratio and the very low levels of x-ray flux required.

Formation of face-centered cubic titanium on a Ni single crystal and in Ni/Ti multilayers

1994 ◽  
Vol 9 (1) ◽  
pp. 31-38 ◽  
Author(s):  
Alan F. Jankowski ◽  
Mark A. Wall
Keyword(s):  
Structural Characteristics ◽  
Single Layer ◽  
High Resolution Electron Microscopy ◽  
Cubic Phase ◽  
Face Centered Cubic ◽  
X Ray Diffraction ◽  
X Ray ◽  
Resolution Electron ◽  
The Face ◽  
Face Centered

The artificial layering of metals can change both physical and structural characteristics from the bulk. The stabilization of polymorphic metallic phases can occur on a dimensional scale that ranges from single overgrowth layers to repetitive layering at the nanoscale. The sputter deposition of crystalline titanium on nickel, as both a single layer and in multilayer form, has produced a face-centered cubic phase of titanium. The atomic structure of the face-centered cubic titanium phase is examined using high resolution electron microscopy in combination with electron and x-ray diffraction.

scholarly journals The excitation of soft X-rays from a single crystal face of nickel

1930 ◽  
Vol 128 (807) ◽  
pp. 37-41 ◽  
Keyword(s):  
Single Crystal ◽  
Crystal Surface ◽  
X Rays ◽  
Crystal Face ◽  
X Ray ◽  
Polycrystalline Metals ◽  
The Face ◽  
Nickel Crystals ◽  
University Of Bristol ◽  
The University

During the progress of our experiments on polycrystalline metals the newly available evidence suggested that crystalline structure might have much to do with the soft X-ray inflections. The fact that the intensity of the inflections was increased by heating the targets to a high temperature by electron bombardment, and that, as had been shown by the experiments of Dr. Nakaya, this same treatment resulted in the formation of a large number of fresh crystal faces on the surface seemed particularly suggestive in this respect. We resolved, therefore, to make experiments on a single crystal surface in the hope that this would result in a simplification of the phenomena. The single crystal used in these experiments was kindly lent to us by Dr. H. H. Potter of the University of Bristol. Nickel crystals are of the face-centred cubic type. The face of the crystal which was used was prepared by Dr. Potter and represented the 100 plane.

A Useful Guide for X-Ray Stress Evaluation (XSE)

1983 ◽  
Vol 27 ◽  
pp. 81-99 ◽  
Author(s):  
Viktor M. Hauk ◽  
Eckard Macherauch
Keyword(s):  
Lattice Strain ◽  
Peak Position ◽  
X Rays ◽  
Linear Lattice ◽  
Stress Evaluation ◽  
X Ray ◽  
Copper Nickel ◽  
Lattice Strains ◽  
Aluminium Copper

AbstractThis paper summarizes experiences available for the measurement of lattice strains in different materials with different wavelengths to evaluate stresses by means of X-rays. The recommendations given are based on previous statements. Some principles of fundamentals of X-ray physics for the recording of interference lines with Ω and ψ-diffractometers are dealt with. Methods applicable for the determination of the peak position of the interference lines, the assessment of linear and non-linear lattice strain distributions, and tine calculation of stresses are outlined. For iron, aluminium, copper, nickel and titanium the constants for practical X-ray stress evaluation (XSE) and the parameters of measurement are tabled.

scholarly journals An X-ray study of the iron-nickel-aluminium ternary equilibrium diagram

1938 ◽  
Vol 166 (926) ◽  
pp. 353-375 ◽  
Keyword(s):  
Ternary System ◽  
Special Interest ◽  
Aluminium Alloys ◽  
Binary Systems ◽  
Permanent Magnets ◽  
Equilibrium Diagram ◽  
Ternary Diagram ◽  
Previous Knowledge ◽  
X Ray ◽  
Iron Nickel

Stimulated by the special interest of iron-nickel-aluminium alloys for the permanent magnet industry, we have made an X-ray investigation of this system. The information obtained has led to a new view of the nature of the permanent magnets of iron, nickel and aluminium, which has been briefly described elsewhere (Bradley and Taylor 1937 a, b, c ). In the present paper we confine ourselves to a description of the X-ray results, which have enabled us to draw a complete ternary diagram representing the phases formed by these metals. The iron-nickel-aluminium alloys are closely related to the systems FeAl, NiAl, CoAl. Every phase which occurs in the ternary system has an analogy in one or another of these binary systems. This makes it possible to interpret the present results in the light of our previous knowledge of those systems.

White-Light Coronal Structures: Streamers and CMEs

1994 ◽  
Vol 144 ◽  
pp. 82
Author(s):  
E. Hildner
Keyword(s):  
Emission Line ◽  
Electron Density ◽  
White Light ◽  
Coronal Mass Ejections ◽  
X Rays ◽  
Solar Cycles ◽  
Temperature Function ◽  
X Ray ◽  
Eclipse Observations ◽  
Coronal Structures

AbstractOver the last twenty years, orbiting coronagraphs have vastly increased the amount of observational material for the whitelight corona. Spanning almost two solar cycles, and augmented by ground-based K-coronameter, emission-line, and eclipse observations, these data allow us to assess,inter alia: the typical and atypical behavior of the corona; how the corona evolves on time scales from minutes to a decade; and (in some respects) the relation between photospheric, coronal, and interplanetary features. This talk will review recent results on these three topics. A remark or two will attempt to relate the whitelight corona between 1.5 and 6 R⊙to the corona seen at lower altitudes in soft X-rays (e.g., with Yohkoh). The whitelight emission depends only on integrated electron density independent of temperature, whereas the soft X-ray emission depends upon the integral of electron density squared times a temperature function. The properties of coronal mass ejections (CMEs) will be reviewed briefly and their relationships to other solar and interplanetary phenomena will be noted.

Chemical Species Identification in an SEM by Changes in Emitted X-Ray Energies

1974 ◽  
Vol 32 ◽  
pp. 570-571
Author(s):  
R. H. Duff
Keyword(s):  
Species Identification ◽  
Valence Electron ◽  
Chemical Species ◽  
X Rays ◽  
Chemical Bonds ◽  
Small Shift ◽  
X Ray ◽  
Electron Transitions ◽  
Peak Energy ◽  
Chemical Combination

A material irradiated with electrons emits x-rays having energies characteristic of the elements present. Chemical combination between elements results in a small shift of the peak energies of these characteristic x-rays because chemical bonds between different elements have different energies. The energy differences of the characteristic x-rays resulting from valence electron transitions can be used to identify the chemical species present and to obtain information about the chemical bond itself. Although these peak-energy shifts have been well known for a number of years, their use for chemical-species identification in small volumes of material was not realized until the development of the electron microprobe.

Influence of X-Ray Induced Fluorescence on Energy Dispersive X-Ray Analysis of Thin Foils

1977 ◽  
Vol 35 ◽  
pp. 328-329
Author(s):  
E. A. Kenik ◽  
J. Bentley
Keyword(s):  
Thin Foil ◽  
Electron Excitation ◽  
Simple Approach ◽  
Foil Thickness ◽  
X Rays ◽  
X Ray ◽  
Hole Spectrum ◽  
Illumination System ◽  
Thin Foils ◽  
Intensity Ratios

Cliff and Lorimer (1) have proposed a simple approach to thin foil x-ray analy sis based on the ratio of x-ray peak intensities. However, there are several experimental pitfalls which must be recognized in obtaining the desired x-ray intensities. Undesirable x-ray induced fluorescence of the specimen can result from various mechanisms and leads to x-ray intensities not characteristic of electron excitation and further results in incorrect intensity ratios.In measuring the x-ray intensity ratio for NiAl as a function of foil thickness, Zaluzec and Fraser (2) found the ratio was not constant for thicknesses where absorption could be neglected. They demonstrated that this effect originated from x-ray induced fluorescence by blocking the beam with lead foil. The primary x-rays arise in the illumination system and result in varying intensity ratios and a finite x-ray spectrum even when the specimen is not intercepting the electron beam, an ‘in-hole’ spectrum. We have developed a second technique for detecting x-ray induced fluorescence based on the magnitude of the ‘in-hole’ spectrum with different filament emission currents and condenser apertures.

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