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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.

BIM idea is increasing the productivity of work. Multidimensional solutions implemented in BIM systems not only allow many structural calculations, but also access the better scheduling, cost estimating, visualizations. In some cases both software and hardware can be a bottleneck. To create an interaction between BIM philosophy and practice of the structural design the experimental research has tested eight structural systems of the high-rise building by way of Building Information Modelling. Multiple variants of the two main bracing system types: (i) a spatial truss and (ii) a spatial shell bracing system. In every model there was checked influence of slab model: with slabs meeting the conditions of a rigid plate (flexible diaphragm slab) and with slabs with no additional stiffening (shell slab). The ULS and SLS requirements were analysed for elements and superstructure. In addition, selected issues concerning scheduling of works (4D BIM) and cost estimating (5D BIM) were discussed with the extensive 3D model developed in line with the BIM standards. Rapid prototyping has enabled to realize the behaviour of structural systems. The outputs of this study are presented in the paper.

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