WorldCat Identities

NORTHWESTERN UNIV EVANSTON ILL Dept. of MATERIALS SCIENCE

Overview
Works: 44 works in 45 publications in 1 language and 51 library holdings
Classifications: TP811.5, 378
Publication Timeline
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Most widely held works by NORTHWESTERN UNIV EVANSTON ILL Dept. of MATERIALS SCIENCE
Defect interactions and relaxation phenomena associated with electronic motion in semiconducting ceramics by C Bauer( Book )

1 edition published in 1969 in English and held by 4 WorldCat member libraries worldwide

Studies of the defect structures and mass transport in alkali halides and nonstoichiometric compounds are reported. Some regular solution statistical mechanical treatments were used to quantitatively predict the pairwise interaction energies between nearest-neighbor point defects in metal-excess, nonstoichiometric compounds. The ionic conductivity of pure and doped NaF was measured over a wide range of temperature and these results were analyzed by a nonlinear least-square method to yield the usual defect parameters. Interdiffusion and defect structure measurements on NiO + CoO solid solutions were carried out at elevated temperatures with the aid of appropriate x-ray methods. The diffusion observations are rationalized on the basis of the equilibrium defect structure inferred from integrated x-ray intensity data on these oxide solid solutions. (Author)
Structure sensitive properties of intermediate solid solutions( Book )

2 editions published between 1967 and 1968 in English and held by 2 WorldCat member libraries worldwide

The report is concerned with an investigation of the effects of point defects on various physical and optical properties of the intermetallic compounds NiAl, CoAl, NiGa, and CoGa. The optical properties of NiAl, CoAl, NiGa, and CoGa indicate that some of these alloys show free electron like behavior for photon energies below about 1 eV, but that others do not. The optical absorption bands that occur in NiAl at about 1 - 2 eV, 2.5 eV, 4.0 eV, and 5 eV have been associated with interband transitions and have been interpreted by the use of a simple rigid band model. CoAl, CoGa and NiGa alloys had an absorption band at 4.0 eV and CoAl and NiGa also had an absorption band at 1 - 2 eV. The 4.0 eV peak was common to all alloys and independent of composition, although the peak position varied slightly in photon energy from one alloy system to the next. The amplitude of the 2.5 eV band in NiAl was strongly compositionally dependent. The electrical resistivities of NiAl, CoAl, NiGa, and CoGa, measured as functions of temperature and composition indicate that these materials are metallic in nature, that the point defects are very important to the conductivity process, and that clustering of the point defects occurs when the composition departs from stoichiometry. Results from measurements of the Hall coefficient and the transverse magneto-resistance in NiAl indicate that a two band model may be necessary to explain the transport processes in NiAl. (Author)
The effects of thermo-mechanical treatments on the substructure in metals and alloys( Book )

1 edition published in 1969 in English and held by 2 WorldCat member libraries worldwide

Dislocation distributions in fatigued single crystals of 3.25% silicon-iron( Book )

1 edition published in 1966 in English and held by 2 WorldCat member libraries worldwide

Fatigue tests were performed on single crystals of 3.25% silicon-iron oriented for single slip. The behavior of dislocations was studied in the early stages of the fatigue process as a function of temperature, number of cycles, and state of stress. A particular emphasis was placed upon observing tangle formation and growth. Part of the tests were performed by cycling about a zero mean stress in 4-point bending. Crystals were fatigued in this manner for various numbers of cycles at both 298K and 495K. The dislocation distributions were investigated by the etch pit technique and electron transmission microscopy. The remainder of the tests were performed in alternating tension. As before, cyrstals were fatigued for various numbers of cycles at both 298K and 425K. In this case, the dislocation distributions were investigated solely by electron transmission microscopy
Tape Focal( Book )

1 edition published in 1973 in English and held by 2 WorldCat member libraries worldwide

It has been found that a 4K DEC minicomputer is insufficient for many worthwhile programming applications. To circumvent this problem FOCAL 1969 has been modified to allow the user whose machine is equipped with a Tennetape Magnetic Cartridge Tape Unit (Model TP 1351) to use the tape as a program storage medium. In this modified version of FOCAL, the FDIS and FADC functions have been deleted as well as the L command and the high speed reader input routine. The command Z now initiates transfer of FOCAL text between tape and core. (Author)
Anomalies in Measurement of Residual Stress by X-Ray Diffraction( Book )

1 edition published in 1974 in English and held by 1 WorldCat member library worldwide

Residual stresses are expected to lead to a linear dependence of the interplanar spacing, d, on sine squared psi (where psi is the sample tilt) and the stress can be obtained from the slope of this line. As a result of the linear dependence a two-tilt method is often employed to obtain the stress. However, when a specimen is subjected to extensive plastic deformation large deviations from a straight line can occur and a two-point method can lead to an erroneous stress determination. The results reported here show that: (1) this is more likely to occur in homogeneous materials than in multiphase materials (2) the oscillations follow closely the variation in peak intensity due to texture (3) the oscillations are caused by microstresses which are due to an 'orientation' effect as suggested by Weidemann. A simple, easy-to-use procedure has been developed and tested to correct the data and obtain the correct macrostress. The materials used were Armco iron, steel and ordered Cu3Au. (Modified author abstract)
Fatigue Crack Propagation in Copper and Copper-Aluminum Single Crystals No. 2( Book )

1 edition published in 1971 in English and held by 1 WorldCat member library worldwide

The effect of crystallographic orientation, temperature and stacking fault energy on the rate of fatigue crack propagation was studied in polycrystalline copper, copper single crystals and copper-aluminum single crystals at room temperature and at liquid nitrogen temperature. A stress intensity factor was used to normalize the crack propagation data. It was found that dislocation cross slip plays a critical role on the rate of fatigue crack propagation. Existing mathematical crack propagation formulae could not explain the data on single crystals. A new fatigue crack propagation model to explain the observed results is proposed. (Author)
Grain rotation associated with the shock deformation of metals and alloys( Book )

1 edition published in 1965 in English and held by 1 WorldCat member library worldwide

A fatigue apparatus for use in studies of crack propagation and dislocation morphology in fatigue by Thomas Benjamin Wade( Book )

1 edition published in 1967 in English and held by 1 WorldCat member library worldwide

A direct stress hydraulic fatigue apparatus has been constructed for use in a study of fatigue behavior and crack propagation in metals. The loading apparatus provides a static load, either tensile or compressive, of up to 290 pounds with a superimposed cyclic load (tensile and/or compressive) of up to 3350 pounds. The frequency of loading may be varied continuously from 560 cpm to 1250 cpm. Both the magnitude of load and the frequency of loading may be altered at any time during a test. Tests may be conducted in various gaseous and vapor environments as well as in vacuum of up to 0.000001. Temperature control is not included in the initial design, but may be added easily. Auxilliary equipment has also been constructed for sample preparation and observation of crack propagation
A STUDY OF THE RELATIVE DUCTILITIES OF TiFe, TiCo, AND TiNi by Ronald Franklin Scholl( Book )

1 edition published in 1968 in English and held by 1 WorldCat member library worldwide

A study of the relative ductilities of binary and ternary compounds of the type TiX where X is Fe, Ni, Co or combinations of these, has been performed by means of three point bending tests at room temperature. The general results of these studies indicate that TiFe or TiCo form a continuous series of solid solutions with TiNi provided the concentration of titatnium remains at 50 atomic percent. The ductility of the binary compounds increases in the order TiFe, TiCo, TiNi. Also, nickel additions to TiFe and TiCo increase their relative ductilities. (Author)
A Program for Least-Squares Analysis of Fourier Coefficients of Peak Shapes and Comparisons of Old and New Procedures( Book )

1 edition published in 1973 in English and held by 1 WorldCat member library worldwide

At least two ways are now available of performing Fourier analysis of peak shape, the older direct ransform method and a new procedure involving least-squares. In addition, there are at least three procedures in the literature of treating the Fourier coefficients to correct for the main errors in the method due to the difficulty in establishing the true background. In the report a new enlarged version of a program for the least-squares procedure is presented along with comments on how to detect errors. This procedure is compared to the transform method. It is shown that both procedures give essentially similar results for particle size and strain. The computing time for the least-squares procedure is an order of magnitude greater. It is thus most useful when there are severe problems due to peak overlap and portions of the data must be removed. But under most situations the transform method is adequate and less expensive. (Author Modified Abstract)
Alloying and Thermal Treatment of Ceramics( Book )

1 edition published in 1972 in English and held by 1 WorldCat member library worldwide

The object of the research was to provide basic information which would be useful for the technology of alloying and thermal treatment of ceramics. Specifically, magnesioferrite precipitates gave substantial strengthening to magnesium oxide. Magnetite precipitates in wustite, iron in iron oxide, and zirconium in zirconia increased both fracture initation energy and fracture strength. Spinodal decomposition was found in cobalt ferrite-cobalt oxide system. Material with very high coercive force resulted. (Author)
Exploratory Basic Research in Physical Sciences - Spinodal Decomposition( Book )

1 edition published in 1974 in English and held by 1 WorldCat member library worldwide

A series of experimental investigations were made which have confirmed the theory of Spinodal Decomposition in alloys. Theoretical studies were also completed which extended the scope of the original theory to cover: (1) Decomposition during continuous cooling. (2) The later stages of the decomposition and (3) Certain types of ordering reactions
SOME OBSERVATIONS ON SHOCK-LOADED COPPER by J. B Cohen( Book )

1 edition published in 1965 in English and held by 1 WorldCat member library worldwide

It is shown that if partial dislocations are involved in twinning in shock-loaded Cu, these must be intrinsic. The twinning shear was measured directly and found to agree with theory. Recrystallization starts at twin intersections and sweeps along the (incoherent) interfaces before advancing into the matrix. (Author)
Fatigue crack propagation in copper and copper-aluminum single crystals by Hitoshi Ishii( Book )

1 edition published in 1970 in English and held by 1 WorldCat member library worldwide

The effects of crystallographic orientation, temperature and stacking fault energy on the rate of fatigue crack propagation have been studied in polycrystalline copper, copper single crystals and copper-aluminum single crystals at room temperature and at liquid nitrogen temperature. The results were discussed in terms of cyclic hardening and the case of dislocation cross slip. (Author)
Rate of growth of fatigue cracks as calculated from the theory of infinitestimal dislocations distributed on a plane( Book )

1 edition published in 1965 in English and held by 1 WorldCat member library worldwide

The Bilby, Cottrell and Swinden crack theory is applied to the problem of the growth of fatigue cracks. It is found that if a total critical displacement is adopted as the fracture criterion, the theory leads to observed growth laws. (Author)
Comparison of Stress Measurements by X-Rays with Three Different Detectors and a Strongly Fluorescing Specimen( Book )

1 edition published in 1977 in English and held by 1 WorldCat member library worldwide

Measurements on the heat affected zone of a weldment are presented using the position sensitive detector and a normal diffractometer equipped with a scintillation detector and a solid state detector. The sample, a surface ground titanium alloy, provided a classic applications problem for the X-ray technique from which a real analysis of the position sensitive detector could be made. The diffraction profile from the Ti alloy is very broad and the fluorescence produces a high background. The fluorescence is easily rejected using a solid state detector, however, the time of analysis is very long. With the position sensitive detector, the combination of increased energy discrimination over the scintillation detector and the simultaneous measurement of many data points over the broad peak enabled the measurements to be made for the same accuracy in much shorter times than for either the solid state detector or the scintillation detector. (Author)
Comment on precipitation in gold-platinum alloys: thermodynamics( Book )

1 edition published in 1965 in English and held by 1 WorldCat member library worldwide

The purpose of the present note is to point out a computational error in a paper on the thermodynamics of the gold-platinum system by van der Toorn and Tiedema. It is also shown that the method used by these authors for calculating the free-energy curve from the phase diagram is, in any case, unreliable because of its extreme sensitivity to small shifts in the position of the phase boundaries
Intrinsic Studies of Materials - Sintering Mechanisms of Defect Oxides( Book )

1 edition published in 1972 in English and held by 1 WorldCat member library worldwide

The report summarizes an investigation of the influence of deviations from stoichiometry on the sintering of the defect oxide, CoO. The eleven conclusions reached in this investigation are listed in this report and among them are: (1) CoO sinters according to volume diffusion kinetics in the initial and intermediate stages, (2) The sintering rate is increased with increasing oxygen partial pressure above 0.001 atmosphere, (3) The calculated volume diffusion coefficients lie between the tracer values for Co and O in single crystals. (Author)
Electronic drift mobilities and space-charge limited currents in lithium-doped zinc oxide by Martin Arthur Seitz( Book )

1 edition published in 1968 in English and held by 1 WorldCat member library worldwide

Electron drift mobilities and lifetimes were measured from 250 to 400K in oriented single crystals of high-resistivity, Li-doped ZnO by determining the transit time across a plane-parallel specimen for electrons which had been photoinjected at one surface by light pulses of about 10 nsec duration. Drift mobilities at 300K ranged from 2 - 8 sq cm/V/sec for the specimens investigated with no orientational dependence being apparent. The observed exponential temperature dependence of the mobility indicated that the electron drift mobility is primarily controlled by thermal release from trapping states, of estimated density 10 to the 16th power/cu cm, lying in a 0.29-eV region below the conduction band. Electron lifetimes, estimated from low-field data, showed some orientation dependence and ranged from 30 - 100 microsec at room temperature, while electron ranges were 0.0001 to 0.001/sq cm/V and were temperature independent. Ohmic electrodes of indium were used to inject electrons into plane-parallel monocrystals of Li-doped ZnO, producing space-charge-limited currents at high fields. The observed current-voltage and current-temperature relations indicated that discrete or narrow bands of electron traps existed in the 0.4-eV and in the 0.72 to 0.80-eV regions below the conduction band edge with densities of 0.004 and 10 to the 17th power/cu cm, respectively. (Author)
 
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Audience level: 0.92 (from 0.78 for Defect int ... to 1.00 for Structure ...)

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English (21)