The effect of chemical etching on the surface relief of NiFe and NiFeCo films and their magnetic parameters is studied. Electron micrograph analysis shows that during the etching inhomogeneities in the film thickness appear with a period of about 1000 A and an amplitude of the thickness fluctuations of about 100 A. This process goes along with the increase of the angular amplitude of the magnetization ripple and coercivity and is well described by Hoffmann's theory. The coercive force component stipulated by pinning of the domain walls on localized defects does not change significantly during the etching. Der EinfluD des chemischen Atzvorgangs auf das Oberflachenrelief und die magnetischen Parameter von NiFe-und NiFeC0:Schichten wird untersucht. Elektronenmikroskopische Untersuchungen zeigten, daD beim Atzen Schichtdickeninhomogenitaten mit einer Periode von ca. 1000 A und Dickenanderungen von etwa 100 A entstehen. Dieser Vorgang ist begleitet von einem Anwachsen der Ripple-Winkelamplitude und der Koerzitivitat. Er 1aBt sich mit der Hoffmannschen Theorie gut beschreiben. Die durch das Haften der Befeichsgrenzen an ortsfesten Fehlstellen bedingte Koerzitivkraftkomponente zeigt wahrend des Atzens keine merkliche Veranderung.

The coercivity HW of a flexible domain wall is calculated considering various mechanisms of domain wall volume and surface pinning such as intergrain boundaries, easy axes angular fluctuations of crystallites, substrate and thin magnetic film surface roughnesses. The HW dependence on thickness D is stipulated chiefly by surface domain wall pinning. Comparison of experimental and calculated HW(D) reveals the contribution of volume and surface inhomogeneities.

With the purpose to estimate the existing methodologies of in-use guaranteed rubber life-time test, the processing of the accelerating rubber ageing results according to State Standard GOST, ISO and Research and Production Enterprise "Progress" methodology is carried out. It is shown that the experimental results analysis provides us with the similar picture, but analytical prognostic method is more advantageous because of its flexibility. Improving of the methods of processing experimental data of rubber accelerated ageing is in the scope of interest of modern mathematical modeling, which lets using more complex functions, reflecting the properties of rubber behaviour in the whole analyzed temperature and time interval without any rejection of experimental data. Such modeling lets more precisely predict rubber behaviour in different operating conditions and carry out computations in conditions of complex temperature-and-time model of rubber products storage and exploitation.

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