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Two kinds of phase stabilization mechanism are discussed and compared: the first is characteristic of the formation of bulk amorphous alloys, in which the high supercooling ability of multicomponent liquids is responsible for the glassy phase stabilization. Here the hindered nucleation of crystalline phases is the center phenomenon. The origin of this hindering is the slowing atomic mobility in the supercooling melt. In contrast the melt supercooling is negligible during the high entropy alloy formation. It is believed that stability of the crystalline single fcc phase is the consequence of the characteristic of high configurational entropy at high temperatures. However, the significance of this entropy-dominated stabilization is overestimated in several references. It has been concluded that transition metal contraction (arising from the d electron participation in the overall bonding state) does also contribute to the high temperature stability of fcc single phase in the high entropy alloys.

Két ötvözetcsalád, a tömbi formában előállított amorf (BMG) és a nagy entrópiájú (HEA) ötvözetek képződési mechanizmusát és stabilitását hasonlítjuk össze jelen közleményben. Az összehasonlítás fő elve az olvadékaik túlhűlési képessége a megszilárdulás folyamatában. A BMG-ötvözetek olvadékai a különböző típusú kémiai kötések miatt nagy túlhűlési hajlamot, s ebből eredően nagy üvegképző hajlamot is mutatnak. Ennek jellemző mechanizmusa a klaszterképződés, amellyel az atommozgékonyság s így a kristálycsíra-képződés is visszaszorul. A HEA-ötvözetek olvadékai nem mutatnak ilyen hajlamot. Nagy hőmérsékleten, közvetlenül az olvadáspont környékén, az olvadékfázissal azonos összetételű, rendezetlen szilárd oldat formájában kristályosodnak. A kétféle olvadéktípusban az eltérő atomi mobilitás tükröződik az olvadékok viszkozitásának eltérő hőmérséklet-függésében is. A HEA-ötvözeteknek a konfigurációs entrópia által dominált fázisstabilitásához elektronszerkezeti tényezők is hozzájárulnak: itt szerepet kap a d-elektronok részvétele az atomok közötti kötésekben.

In the present work the comparison of the effect of traditional, pulse and stress annealing is made by monitoring the important mechanical and magnetic properties of FINEMET type amorphous precursor alloy. The magnetic properties were determined from the shape of magnetization curve (coercive force, anisotropy) during various heat treatments and the mechanical properties were measured using brittleness test. The traditional heat treatments were performed in resistance furnace and the magnetic measurements were performed in astatic magnetometer. The pulse and stress annealing (as well as their combinations) were carried out inside in the magnetometer. The temperature of pulse heat treatments is regulated with the length of current pulse flowing through the sample. After each pulses the magnetization curves were measured in-situ, in the magnetometer.

In my study I present the urban environment as a space for walking a dog from the perspective of the dog owner. I analyze the activity of walking a dog as the most characteristic manifestation of the contact between public space and the dog owner, and using the method of mental mapping. I explore how dog owners perceive public space when walking their dogs. The initial hypothesis of my research was that dog owners use public spaces differently from others when they try to construct and satisfy the (assumed) needs of another creature from their viewpoint. During walks, owners use public spaces in a way that, according to their conception, suits their dogs the most. We could also say that they aim to use space from the dog’s perspective, as they can conceive of this. Urban dog keepers vary in terms of motivation, dog-keeping practices and lifestyle, thus we cannot speak about them in general. However, through examining different individuals and groups it is possible to identify some features of the “dog lifestyle.” This is important as there is a growing need to identify and understand this specific lifestyle model. In today’s urbanism, the role of multifunctional spaces is increasingly significant as such spaces are being created not to the detriment of the different sub-social groups, but by taking specific needs into consideration.

A short survey is reported on the advantageous and disadvantageous properties of soft magnetic glassy tapes to build stator and rotor elements for the increase of motor efficiency. The relative high saturation magnetization and the relative permeability of these alloy groups seem to be promising in this application field. On the other hand, the sample thickness (30 µm) displays limitations in terms of a filling factor. High hardness of tapes hinders the effectivity of mechanical shaping. Laser cutting can be successful as shaping method, presuming that the extension (thickness) of heat affected zone (HAZ) can be successfully reduced below 50µm, avoiding the brittleness evolution.

In my study I present the urban environment as a space for walking a dog from the perspective of the dog owner. I analyze the activity of walking a dog as the most characteristic manifestation of the contact between public space and the dog owner, and using the method of mental mapping I explore how dog owners perceive public space when walking their dogs. The initial hypothesis of my research was that dog owners use public spaces differently from others when they try to construct and satisfy the (assumed) needs of another creature from their viewpoint. During walks, owners use public spaces in a way that, according to their conception, suits their dogs the most. We could also say that they aim to use space from the dog’s perspective, as they can conceive of this. Urban dog keepers vary in terms of motivation, dog-keeping practices and lifestyle, thus we cannot speak about them in general. However, through examining different individuals and groups it is possible to identify some features of the “dog lifestyle.” This is important as there is a growing need to identify and understand this specific lifestyle model. In today’s urbanism, the role of multifunctional spaces is increasingly significant as such spaces are being created not to the detriment of the different sub-social groups, but by taking specific needs into consideration.

The focus of this paper is the deeper understanding of the effect of the change in the electronic structure on the wetting angle and transport properties. For this purpose, using the alloys from the earlier study, the thermopower has been measured and the Seebeck coefficient has also been determined in room temperature (solidified state). During the experiments in both case the modification of the electronic structure were performed by alloying on a way, that the investigated systems are terminal (α) solutions in solid state. The concentration dependence of property changes are interpreted on the bases of free electron model elaborated earlier for this alloy types. This prediction fits well also to the concentration dependence of heat of formation in these alloys. Similar concentration dependence has been also found between the Seebeck coefficient, the resistivity and the heat of mixing in α-phase Fe-Ni alloys. The shift of thermopower were also monitored in order to detect the crystallization (first oreder transformation) starting form amorphous Fe-B alloys.

A survey of the cluster formation tendency and mechanism in transition metal-based glassy alloys is made with an emphasis on their manifestation in various physical properties. The cluster formation is partially inherited from the supercooling of the melt. However, it also develops due to the interaction between dissolved hydrogen and the frozen glassy structure. The glassy state as “cluster assembly” is regarded as a structural background for the interpretation of several anomalous concentration dependences of thermal and magnetic properties in these glasses. We will focus on the manifestation of alloying effects, the relation between irreversible and reversible structural relaxations both in the high, and low temperature range (observed near to the glass transition or after low temperature storage). The development of the cluster assembly is the consequence of the co-existence of various bonding types between the alloy components. These are brought together in the melt, ensuring sufficient glass-forming ability. The nucleation mechanism of the amorphous-nanocrystalline transformation is also explained as a cluster phenomenon, which significantly contributes to the evolution of magnetic ultra-softness in FINEMET-type alloys. Finally, the role of the quenched-in cluster structure in the mechanism of reversible and irreversible H-absorption is discussed. Irreversible H-induced structural rearrangements can appear as microphase separation in multicomponent systems, governed by the affinity difference between the metallic components and the absorbed hydrogen. This kind of H-induced reordering is responsible for the “volume activation” of amorphous H-storage alloys and it also causes the gradual breakdown of storage capacity during cyclic absorption–desorption steps. This article mainly focuses on the cluster phenomena in Fe-based glasses because of its unique combination of high mechanical strength, strong corrosion resistance, good thermal stability and excellent magnetic properties.