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SUMMARY

Borukh I. V. Influence of hydrogen treatment on structure and magnetic

properties of materials based on Nd2Fe14B and SmCo5 intermetallics. -

Qualifying scientific paper on the rights of the manuscript.

Thesis for a degree of Candidate of Sciences (Engineering) inspeciality

05.02.01 – materialsscience. H. V. Karpenko Physico-Mechanical Institute NASU,

Lviv, 2021.

The thesis for a degree of Candidate of Sciences (Engineering) is devoted to

the development of the method of obtaining sintered nanostructured magnets from

rare earth – transition metal alloys using hydrogen – initiated phase

transformations – the HDDR method. Differential thermal analysis (DTA), X-ray

phase analysis (X-ray diffraction), method of scanning electron microscopy

(SEM), energy-dispersive X-ray spectrometry and magnetic hysteresis loop

measurements were used to study the conditions of processing Nd 11,7Fe 82,3B 6,

Nd 16Fe 76B 8, Nd 11,7Fe 81,1Zr 1,2B 6, Nd 16Fe 73,9Zr 2,1B 8 and Sm (Co, T) 5, T = Zr, V, Ti

ferromagnetic materials at separate stages of sintered magnets production:

grinding, pressing and sintering.

The relationship between the parameters of grinding alloys and the

parameters of hydrogen treatment to obtain magnetically anisotropic materials with

crushed to the nanolevel microstructure is studied. The peculiarities of HDDR in

the powders of alloys, during their sintering and in heat treatment of sintered

SmCo 5, magnets at a hydrogen pressure up to 0.5 MPa in the temperature range of

20–950 ° С are studied. It is found that after solid-HDDR at low hydrogen pressure

in alloys without zirconium ( Nd 11,7Fe 82,3B 6, and Nd 16Fe 76B 8) milled grains of

Nd 2Fe 14B phase with dimensions of 200 nm are formed, and after solid-HDDR at

low pressure of hydrogen in alloys with zirconium (Nd 11,7Fe 81,1Zr 1,2B 6 and

Nd 16Fe 73,9Zr 2,1B 8) milled grains of the Nd 2Fe 14B phase two times smaller in size -

100-200 nm, are formed.