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A new alloy exhibiting high glass-forming ability was developed with the composition Fe70.7C6.7P10.4B5Si1.1Mn0.1Cr2Mo2Ga2. This alloy exhibited excellent castability enabling net-shape-casting. The samples were prepared by copper-mould casting in conical rod form which has a small diameter of 3 mm, a large diameter of 4 mm, and a length of 54 mm, as well as in ring form with an outer diameter of 26 mm, an inner diameter of 18 mm and a thickness of 1 mm. The BS and HC values in DC conditions determined for the ring sample in the as-cast state are 0.45 T and 1.7 A/m, respectively, and for the ribbon in the as-cast state 0.5 T and 3.8 A/m, respectively. On the basis of the measured properties, large industrial use of this new alloy can be predicted.

An additional cryogenic effect will be reported obtained on hypo-eutectic FeB alloys. After resting the samples at low temperature (such as liquid N2, 77 K), the decrease in H solubility was detected by measuring the time dependence of pressure change in a hermetically closed chamber. The cryogenic treatment also caused a systematic lowering of the Curie temperature of the amorphous phase (TCam), similarly to that, observed in other types of Fe-based glasses.

The irreversible and reversible Curie-point relaxation was studied in FeNi-based liquid-quenched glasses. An unusual diffusionless transformation was detected during low temperature ageing in liquid N2 causing a hidden structural imprint in the glassy samples. The coercive force and permeability are also modified by this transformation.

Magnetic and structural properties of amorphous Co80-xCrxSi6B14, x=0, 2, 4, 6 and 8 at. , alloys were investigated. Temperature dependences of saturation magnetizations and relative initial susceptibilities were compared with the temperature dependences of heat flow obtained by DSC technique. Two crystallization temperatures were obtained in the temperature range 300-870 K. First crystallization leads to the formation of magnetically harder ferromagnetic material. Second crystallization additionally increases magnetization of the samples with 0 and 2 at. Cr and decreases it for higher Cr content. Concentration dependences of saturation magnetization, Curie as well as crystallization temperatures are reported. Increase of Cr contents decreases coercive fields of alloys. The influence of the under-critical annealing on the coercivity is discussed.

The influence of chromium admixture on magnetic properties of amorphous FeB ribbons in hydrogenation and dehydrogenation processes is studied. The measurements of demagnetization factor, the anisotropy constant induced by internal stress, and coercivity indicate that the presence of Cr atoms increases the internal stress in the structure and probably influences the size of stress centers created by hydrogenation. The concentration of sites which can be accessed and occupied by hydrogen, hydrogen diffusion rate and hydrogen atom distribution in a sample cross-section depend on Cr content in a complex way.

The time dependence of dehydrogenation is investigated by the measurement of stress sensitive magnetic properties in FINEMET type alloys after various degree of amorphous-nanocrystalline transformation. It was found that defect structure is dominantly responsible for the sensitivity to hydrogen absorption and desorption in this alloy, and the nanograin formation has only a minor significance in this respect.

The amorphous-crystalline transformations were studied in the case of glassy Fe70.7C6.7P10.4B5Si1.1Mn0.1Cr2Mo2Ga2 alloy prepared in the form of bulk ring, and thin ribbon (thicknesses are 1 mm, and 24 μm respectively). Although both samples are “XRD amorphous” there are clear differences in the devitrification behaviour as it can be revealed by DSC and thermo-magnetic measurements. These differences are discussed in terms of inherent structural heterogeneity of the bulk sample.

Continuing the earlier experiments, a series of new effects will be presented in this paper which demonstrate, that the amorphous Curie temperature (TCam) can be altered by resting the samples at low temperature such as (liquid N2, 77 K). The sign and magnitude of this shift depends on the alloy composition, but can also be influenced by the rate of liquid quench applied during the ribbon formation. TCam is lowered during liquid N2 treatments for the binary Fe85B15 glass. The effect is the same when a small amount of Si is added to the Fe85B15. Exceeding the critical concentration limit of the Si, the sign of TCam changes.