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The paper presents an idea of the laboratory test stand for evaluation of the application potential of magnetobarocaloric materials. These materials are characterized by the temperature change under stimulation by a magnetic field and mechanical loading. This property of the material can be used for construction of cooling and heating devices. Thanks to the ecofriendly character of the solutions based on this material it may replace, in the near future, nowadays solutions based on the gas compression-decompression method. The presented laboratory test stand will allow comparison of the several groups of materials in terms of their application in modern cooling systems. The paper shows the main ideas behind the construction and working principles of the system. To obtain a change in the temperature of the tested material it will be subjected to the magnetic field generated by permanent magnets and mechanical loading generated with use of a universal testing machine. Loading will cause a uniaxial tension state in the material. Magnetobarocaloric material, working as a refrigerant in the device, will be applied as a multiflow system. The test stand will work in a modified active magnetic regenerator (AMR) cycle that is most commonly used in prototypes of magnetic refrigerators. This cycle will be adapted for the use of mechanical loading in addition to magnetic stimulation. The test stand presented in this paper is currently under construction. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

This paper presents the design and measuring potential of the latest generation of the magnetic scanner called Magscanner-Maglab System (MMS) which enables a fast acquisition of 3D signals from magnetic sensors and their visualization as digitalized magnetic images for a variety of flat and cylindrical objects. MMS can be used as entirely autonomous or combined (through common control) with a typical material testing machine for static load and fatigue tests. The system can be used to investigate magnetomechanical phenomena and identify their models in experimental mechanics, as well as detect and locate strain fields, areas of plastic deformations and cracks in industrial processes. It has been used recently to measure the magnetic field around objects subjected to technological processing in order to check their quality. [ABSTRACT FROM AUTHOR]

The microstructure and some magnetic properties of the bulk amorphous (Fe0.61Co0.10Zr0.025Hf0.025Ti0.02W0.02B0.20)100-xYx(x = 0 or 2) alloys are studied. The as-quenched and annealed at 720 K for 15-mm alloys, well below the crystallization temperature, as confirmed by X-ray diffraction and Mössbauer spectroscopy studies, are fully amorphous. The investigated alloys are soft magnetic ferromagnets and exhibit relatively high magnetic susceptibility at low magnetic fields. However, the alloys show broad disaccommodation spectra characteristic of amorphous materials. The intensity of disaccommodation distinctly decreases after the addition of 2 at. % of Y to the amorphous Fe61Co10Zr2.5Hf2.5Ti2W2B20 alloy and also after annealing at 720 K for 15 mm. From the analysis of disaccommodation curves, the average activation energies of elementary processes are estimated. The obtained values of the activation energies, equal to about 1.2 eV, and preexponential factor in Arrhenius law in order of 10-15's indicate that observed disaccommodation phenomenon is connected with the ordering of atom pairs near free volumes. In higher magnetic fields, the magnetization fulfils M/Ms ∼ 1/µ0H law, pointing out the presence of quasi-dislocation dipoles with the width lower than the exchange length. After the addition of yttrium to the amorphous Fe61Co10Zr2.5Hf2.5Ti2W2B20 alloy and the annealing of the samples at 720 K for 15 mm, we observe the decrease of the quasi-dislocation dipoles width. [ABSTRACT FROM AUTHOR]