Exploitable results Low cost dry coating system for high efficiency soft magnetic composites Currently, the materials used for (dielectromagnetics) soft magnetic composites are processed by complex wet processing techniques typically incorporating volatile and flammable organic solvents as a media to form insulating coatings on iron powder. The resultant functionalised powders are substantially value added. Within this project we have developed an effective low cost alternative route for developing such coatings based on dry blending technology with suitable additives, which can be readily accomplished using standard powder processing equipment routinely available within all powder metallurgy component manufacturers. This offers an opportunity either for the production and supply of very low cost proprietary coated powders by powder manufacturers, or alternatively for the licensing of the coating technology (and the supply of the appropriate coating chemicals) to component producers to enable them to modify powders in house to their own specifications at low cost. Organo-silicate insulating binder system for metal powders allowing thermal annealing to reduce magnetic losses We have developed an effective thermally stable binder/coating system based on organo-silicate materials, which can be used in combination with metallic powders to provide annealable dielectromagnetic composites - A key deliverable for the project. These systems allow thermal annealing to temperatures between 450 and 600C, the latter being a significant improvement on the best currently available systems. This system is one of three variants that we have developed, and offers intermediate cost and performance between the three (i.e. neither the lowest cost nor the highest performance). Of the three systems developed it was thus considered to be less commercially attractive and was therefore chosen instead as a model system through which the properties and behaviour of dielectromagnetics in general could be scientifically explained and discussed in the open literature. This is considered to be a vital step in achieving the necessary confidence to allow designers of electrical machines to specify and use dielectromagnetics of all types in their products. This crucial dissemination route will involve a number of technical and trade journal and international conference papers. Influence of geometry and temperature on total energy loss of dielectromagnetics The influence of geometry on magnetic properties of magnetic cores made of insulated and non-insulated soft magnetic composites was observed. The obtained results indicate that in case of the dielectromagnetics, in the range of tested heights (h=2mm, 4mm, 6mm, 8mm, 10mm) the size of the active cross section of the specimens does not have any influence on the elementary magnetic properties. This means that in case of dielectromagnetics it is possible to design the dielectromagnetic magnetic cores of different shape and sizes without the concern of skin effect and, subsequently, deterioration of magnetic properties (drop of induction, increase of losses), which accompany the increase of height of the magnetic core. However, one has to take into consideration the fact that some limiting height, the transgression of which makes the dielectromagnetic powder stop condensing homogenously, does exist and that the geometry of the magnetic core might have an influence on the obtained magnetic properties. On the other hand, in the magnetic core made of dielectromagnetics magnetic flux flowing through the whole volume of the core (which is sometimes very large) can cause change of magnetic core temperature, particularly at higher frequencies. This increase of temperature is mainly the result of hysteresis and eddy current loss. It is commonly known that the change of magnetic core's operating temperature changes its magnetic properties. That is why, the next step taken by WP2 when it comes to dielectromagnetics' behaviour in applications was the examination of temperature's effect on dielectromagnetics' total energy. The tests have been carried out with different temperatures of magnetic core 24°C, 40°C, 60°C, 80°C, 100°C at frequencies: 5Hz, 50Hz, 400Hz, 800Hz. The cores were made of pure iron powder and of dielectromagnetic powders: iron powder with a 0.1% addition of dielectric and iron powder with a 0.5% addition of dielectric. The tests showed that the sample's temperature has an influence on total energy loss generated inside it. The strongest influence was noted for pure iron powder sample in which increase of total energy loss was observed with increase of temperature (ruling out 5Hz where total energy loss decreases along with temperature increase). However, in case of dielectromagnetics, the behaviour of total energy loss with change of temperature is different from the one in case of iron: total energy loss decrease with increase of temperature in the whole range of measuring frequencies. This decrease is nearly independent from the exciting frequency and very similar for both kinds of tested dielectromagnetics. Between 24°C and 100°C it equals about 6-7%. That is why it is advisable to measure the magnetic properties of materials in temperature they really work in. The knowledge of these properties is necessary for the correct calculation of magnetic circuit and has an essential influence on final design and parameters of the electrical machines. New system for testing magnetic properties at high frequencies and under rotating magnetic fields As planned within the project, we have developed a completely new form of measuring system by which the properties of dielectromagnetic composites can be more accurately and realistically measured. MAG-TD200 computerised measuring system provides a fully automatic process for the complex testing of the magnetic materials properties. It enables testing of magnetic properties in alternating fields at frequency range from 5 to 2000Hz (the range of frequency was extended in relation to previous project assumption 1600Hz), and in rotational fields with any elliptical degree and direction of rotation at frequency range from 20 to 400Hz (the range of frequency was extended in regards to the one in previous project assumption -200Hz). The possibility of measuring magnetic properties of materials under rotational fields makes this system unique on a global scale. The measurements under alternating fields can be taken on ring samples, strips (by means of Epstein frame), single sheet tester and yokes for samples in shape of beams. The measurements under rotational fields can be taken on a cylindrical (for powder composite and electrical sheets) or square specimens (electrical sheets), with winded two coils orthogonal to each other for induction measurement of each measurement channel. MAG TD200 system enables, among others, measuring of the following characteristics of magnetic materials: magnetization curve (up to magnetic field intensity H=15kA/m or magnetic induction B=2.0T), coercive field intensity Hc, remanence Br, total energy loss with division into hysteresis loss and eddy-current loss, amplitudal relative magnetic permeability. The "peep" of hysteresis loop for the required value of polarization and magnetic field intensity with full description of the parameters is also possible. For interpretation of results, the possibility of checking Fourier series distribution with full description and spectral lines diagram for each measuring point of magnetic field intensity, total energy loss, specific apparent loss (with determination of deformation loss) and polarization in some cases is very useful. The system also has the possibility of controlling the measured object's temperature and conducting measurements in wide temperature range. It is very important, especially during measurements at high frequencies during which temperature of the measured object might be changing, as the result of generating high-energy loss. In case of rotational fields, all of the above characteristics are measured and determined for two channels - x and y - simultaneously. Moreover, in rotational fields, MAG-TD200 system enables measuring and determination of rotational loss, angle between H and B vectors PhaXY, peak value of field intensity Hm, peak value of polarization Jm, hysteresis loop for required polarization value: Bx=f(Hx), By=f(Hy), By=f(Jx), Hy=f(Hx), By=f(Bx) and Hy=f(Hx) simultaneously. Additionally, the method for measuring total energy loss anisotropy by means a yoke for rotational fields has been elaborated. The obtained results of total energy loss anisotropy, measured by means of the developed method (vector method) and by anisometer are very similar. Fatigue data for dielectromagnetic composites At an early stage of the project the lack of available fatigue data for dielectromagnetic materials was identified as a potential disincentive for designers interested in producing new motors or electrical machines to take advantage of the benefits of the new materials. In order to remedy this situation, a programme of fatigue testing was initiated, beginning with the characterisation of existing materials. The programme consists of establishing S-N curves for two different families of dielectromagnetic materials using a resonant fatigue-testing machine, with samples oriented both parallel with and perpendicular to the pressing axis. The results from this part of the programme indicate that the endurance limit for iron-resin dielectromagnetic materials is higher in proportion to the tensile strength than is the case for conventional PM materials. The testing has also considered the effect of operating frequency on the fatigue behaviour of dielectromagnetic materials. It is the intention of the consortium that the results of the fatigue study should be placed in the public domain in order to foment the adoption of the new materials and technology. Innovative method of improving dielectromagnetics properties We have developed a novel method of dielectromagnetoic powder manufacture based on isolation of the fine dielectric uncoated iron particles by coarse dielectric coated ones. It allows for attaining better properties of dielectromagnetics (in comparison to the ones of dielectromagnetics made of a powder with particles all being coated) with maintaining low eddy current and hysteresis loss. Patent application for the protection of the method of improving the properties of dielectromagnetics mentioned above was applied to the European Patent Office. Searching for OpenAIRE data... 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