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The NdxFe1-x amorphous thin films with x=0.06-0.80 were prepared at 77 K by flash evaporation. The results show that the amorphous films are stable at room temperature when 0.192 and T untill the crystallization occurs. The crystallization of the amorphous films can not be completed at a certain fixed temperature but over a temperature range.

The magnetic properties are reported for amorphous NdxFe1-x films prepared by flash e-vaporation at 77K. The result indicates that Nd is nearly random distributed with a small net moment parallel to the Fe moments which posseses a ferromagnetic alignment. The distribution angle of the Nd-atomic moments increases slightly with increasing x. The ordering temperature Tc is dependent on applied field and the values of Tc from Arrott-plot or other evaluation methods are different. This can be attributed to exsistence of clusters with different Tc in the film. The exchange interaction, but not the spontaneous magnetisation, is strongly influenced by the preparation conditions.

Simultaneous grain boundary-, surface- and lattice diffusion in hypothetical thin film couples of miscible components was computer simulated. On this basis the diffusion into fixed and moving grain boundaries is discussed with respect to the determination of diffusivities by depth profiling methods. The data evaluated from the synthesised depth profiles according to Whipple-Le Claire as well as to Gilmer and Farrell were compared with the diffusivities used for the computation. Agreement was found for systems with a fixed grain boundary network. Moving grain boundaries, however, may cause errors of an order of magnitude towards lower grain boundary diffusivities

In order to separate diffusion induced changes in the electrical resistivity of quench-condensed amorphous AgCu alloy films from such arising from other causes several trial experiments have been performed. Such films consisting of alternating Ag60Cu40/Ag40Cu60 layers showed a specific resistance rise which revealed the following peculiarities: 1. The duration of this increase is inversly proportional to the square of the individual Ag60Cu40/Ag40Cu60 couple thickness, 2. The increase is suppressed if rapid heating up to the crystallization temperature is performed and 3. It is not appearing in homogeneous layers. These results give clear evidence that the observed effect is arising from diffusional intermixing only. Diffusion coefficients averaged over the annealing period are estimated as D = 8.7 x 10-15 cm2s-1 x exp 0.89 eV/kT.

A short literature survey on the subject is given with special emphasis on discrepancies and contradictional interpretations of results. Our own experiments on thin copper films evaporated onto glass substrates at different condensation temperatures are reported. Density values were calculated from the film thickness, which was measured by Kiessig's method and from the deposited mass determined by atomic absorption spectrometry as well as gravimetric measurements. The density defect decreases with increasing film thickness, as already established, and also with temperature. From these results together with those obtained from films which were deposited during a rapid temperature rise from the low substrate temperature to room temperature we conclude that the density defect is localized at the substrate - film boundary.

The change of x-ray optical properties during diffusional alloy formation can be used for the evaluation of diffusion parameters in bimetallic thin film couples. The most pronounced phenomenon governed by these properties are the known Kiessig interferences which can be observed in the specular scattered x-ray beam at very small glancing angles. From these interference patterns diffusion data can be obtained by a comparison with calculated reflection curves based on a proper model for diffusion. The most useful thickness range for this method is below 1000 Å, where common x-ray techniques lose their applicability. Since the changes in the interference patterns are most significant in the early diffusion stages, this technique is most suitable for observing initial interdiffusion, which very often occurs with enhanced diffusion rates. The experimental check of the method is performed in the Au-Ag system. Bimetallic films of the pure components were annealed at temperatures between 200 and 300 °C. In this temperature range diffusion parameters from 10-16 to 10-14 cm2/s were found in good agreement with values obtained by other techniques.

The validity of some assumptions included in the theoretical basis of several x-ray methods for the determination of concentration spectra in inhomogeneous solids, is analysed critically by theoretical considerations.

The analysis of X-ray reflections allows for the determination of the grain dimension in the direction of the bisector of the incident and scattered radiation. It is shown that correct results will be obtained only as long as the grain dimensions perpendicular to this direction are sufficiently large. The possible errors are estimated. The conditions for the determination of the shape anisotropy are discussed.

A general expression for x-ray interference profiles of a binary alloy showing crystals of different concentration and thus different lattice dimensions is deduced. This expression contains previously reported relations as special cases, which are discussed briefly. It is not restricted to systems of total solid solubility or cubic lattice.

Contrary to brittle material, the equilibrium grainsize for ductile powders is often approached as an oscillatory function of time. The following paper investigates this behaviour by means of a geometrical analysis of the powder particles, using wet-milled aluminium powder as an example. For the description of the milling kinetics we have used Hüttig's milling functions which are obtained from a sieve analysis, the measuring of the specific area of a powder monolayer, and the determination of the space-filling.

Es werden die systematischen und statistischen Fehler bei der Ermittlung der Kristallitvolumina nach STEPHEN und BARNES sowie nach EBEL behandelt. Außerdem wird eine vereinfachte Variante der erstgenannten Methode, welche im Gegensatz zu dieser nur eine Aufnahme erfordert, aufgezeigt. Aus einer Gegenüberstellung der drei Verfahren ergeben sich ihre zweckmäßigen Anwendungsbereiche. Zahl und Schwärzung der Interferenzpunkte auf einem Debye-Scherrer-Kreis gestatten eine Bestimmung des mittleren Kristallitvolumens, sowie der Halbwertsbreite der Volumsverteilung der kohärent streuenden Gitterbereiche in dem vom einfallenden Röntgen-Strahlenbündel erfaßten Probenvolumen. Ein Vergleich der Verfahren sowie eine Erörterung der Fehlermöglichkeiten ist Gegenstand der folgenden Betrachtungen.

Gitterdefekte erhöhen den Energieinhalt eines Festkörpers. Dies zeigt sich bei chemischen Umsetzungen in einem zusätzlichen Beitrag zur Reaktionsenthalpie. Im folgenden wird über die Veränderung der Lösungswärme von Aluminiumpulver durch eine Sdiwingmahlbehandlung mit steigender Mahldauer berichtet. Die Zunahme der Lösungswärme entspricht den bei einer Wärmebehandlung ermittelten Werten der Speicherenergie1.

Vickers hardness tests on microscopic small bodies, e.g., fibers, powder particles, thin layers, etc., require imprint dimensions near or even below the resolution limits of light microscopes. Hence, to detect and evaluate these miniature imprints a scanning electron microscope (SEM) has to be used. For such observations in a SEM, nonconducting samples have to be coated with a thin conductive layer. The influence of these films on the imprint size and thus on the hardness value can be rather significant. On the basis of a systematic investigation in the case of a layer much softer than the sample to be tested, methods for an elimination of the layer's contribution to the hardness result are presented.

In the submicroscopic range crystallite sizes which are determined by means of various X-Ray methods show often considerable discrepancies .The reason for this are different analytical approximations made in the underlying theories of these methods. The results of the analysis of the X-Ray line width of wet-milled alluminium powder are compared with crystallite sizes which were obtained by dark-field electron mircoscopy. The basic method was Hall's analysis using different elimination procedures for apparative parameters and grain-size and internal strain contributions. The best agreement with the electron microscopic data was obtained by the Wagner-Aqua method combined with an approximation of the strain- and particle size profiles by Gaussian functions.