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Electron beam lithography combined with electrodeposition was used to fabricate arrays of NiFe and Fe nanomagnets with high aspect ratios (height/diameter). MFM-measurements show the single domain behavior of the NiFe-pillars, which have an easy axis parallel to their long axis. AGM-measurements carried out on large NiFe-arrays clearly show the increasing importance of interaction effects with decreasing periodicity. On top of overgrown Fe-pillars a nanocrystalline structure can be observed.

A permanent magnet alloy composed of 52% Co, 8% V, 4% Cr,balance Fe was subjected to severe cold forming by drawing or rolling to produce a reduction in cross-sectional area of over 90%,and to subsequent heat treatments at temperatures varying between 20 and 700°C, after which the following properties were measured: magnetic saturation as a function of temperature in the range from −200 to +700°C; coercive force as a function of temperature in the range from −200 to +400°C; remanence;torque in the magnetic field, anisotropy energy, and longitudinal magnetostriction as a function of temperature in the range from+20 to +400°C. Vickers hardness, ultimate tensile strength,Young's modulus, and coefficient of expansion were also determined in some cases and electron micrographs of the structure taken. The permanent magnet alloy tested consists of a fine twophase structure, the body-centered cubic α phase alone being ferromagnetic above room temperature, while the second phase becomes ferromagnetic only at temperatures below room temperature. Magnetizing and demagnetizing of this alloy, too, is brought about chiefly by domain rotation. Basically, permanent magnetcharacteristics are not produced by crystal anisotropy or anisotropy of directional order but by a uniaxial anisotropy which may be either a shape or a strain anisotropy. The measured magnetic properties can be more easily explained by an anisotropy of internal stresses which in one model concept is produced by the process of α-γ transformation because of the clearcut textures of both components. There are also indications that the mutual transformation of the two structure components is coincident with noticeable shifts in chemical composition or order, particularly in the γ phase.

The magnetical rotation of the plane of polarisation and the ellipticity of the reflected and transmitted light through magnetically saturated, evaporated layers of iron, cobalt and nickel (30 to 100 mtz ) are dependent one another according to the tShenomenological theory of W. VOIGT. The four measured magnetooptical angles are however independent each other. By comparison of other physical properties, except the magnetooptical ones, (f.e. magnetical saturation, optical absorption) measured respectively with transmitted and with reflected light, we try to prove, that the layers are homogenous at least near the glass-side. The linear increase of Faraday-rotation and optical absorption with the thickness of the layer supports this assumption. Then the independence can only be explaned by a magnetooptical term in the second equation of Maxwell also (precession of spin).The knowledge of the optical constants ist necessary for the comparison ot magnetooptical ones. They are find out by measurements of intensity only, using the transmitted light and the reflected light at both sides of the layer. By supernumerary kinds of determination the fonlt is estimated. The method of Drude is adapted to measurements of intensity and then applied on the glasside too. The results on this side agree with those of transmitted light, the air-side differs a little.

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