**2. Materials and Methods**

The samples of Zr55Cu30Al15Ni5 amorphous alloy were produced by melting and quenching into a copper mold. They were rods with a diameter of 8 mm. The thermal analysis of the alloy was performed by differential scanning calorimetry (DSC) (Perkin-Elmer DSC-7). The Zr55Cu30Al15Ni5 bulk amorphous alloy was heated to the preset temperatures (up to 848 K), then cooled to room temperature in the calorimeter with Ar flow. The use of an argon atmosphere avoided oxidation of the sample. The heating rates (β) were 5, 10, 20, and 40 K/min. The kinetic characteristics of the crystallization reaction were determined by the obtained series of DSC curves. The error in the measurement of activation energy (Ea) and temperature was 1.9 kJ/mol and 3 K, respectively.

The samples were deformed by high-pressure torsion (HPT). The samples of an initial alloy were cut into disks with a thickness of 0.5 mm and polished before deformation. They were deformed at a rate of 1 rotation per minute, with deformation at 1, 5, and 10 rotations being used. The deformation was carried out at a pressure of 6 GPa at room temperature. The deformation degree was estimated by the formula:

$$\varepsilon = \ln\left(1 + \left(\frac{q \cdot r}{h}\right)^2\right)^{0.5} + \ln(\frac{h\_0}{h})\tag{1}$$

where: *r* is the radius of a sample, u is the angle of the punch rotation, *h0* is the thickness of an initial sample, *h* is the thickness of a deformed sample [17]. Thus, *e* = 4.8, 6.4, 7.1 for 1, 5, and 10 rotations, respectively. The deformation degree was determined for the middle of the sample radius. The diameter of the sample was 8 mm. All the subsequent measurements were performed for a sample region which was in the middle of the deformed sample radius. The deformation of the samples was carried out at room temperature. No oxide layer was found on the surface after deformation. The structural studies were carried out by X-ray diffraction (using Co Kα and Mo Kα radiations), high-resolution transmission electron microscopy (HREM), scanning electron microscopy (SEM), and X-ray microanalysis (EDS). A focused ion beam (FIB) was used to prepare electron microscope foils from certain regions of the deformed samples.
