This study focuses on the effect of replacing molybdenum with vanadium in rapidly quenched quasi-high-entropy alloys of the Fe-Co-Ni-Cr-(Mo,V)-B system. The paper analyzes the effect of the chemical composition of alloys with different boron content levels on structure formation, characteristic temperatures of alloys, and mechanical properties. An analysis of the relationship between the structure of alloys and their properties is performed. X-ray diffraction and scanning electron microscopy methods were used in the work to establish the structural dependencies. Characteristic temperatures were determined by differential scanning calorimetry. It is suggested that the addition of vanadium to the alloys of this system leads to the formation of vanadium nitrides in the structure, due to the binding of dissolved nitrogen. Furthermore, it is found that replacing molybdenum with vanadium leads to an increase in the thermal stability of the amorphous phase.

Cold rolling (CR) with thickness reduction of 10%, 30%, and 50% was applied to Zr₅₀Cu₄₄Al₆ and Zr_49.5Cu₄₄Al₆Nb_0.5 metallic glassy ribbon samples. The XRD patterns showed the amorphousness of all samples after casting and CR processes. The SEM images indicated the formation of multiple shear bands (SBs) owing to plastic deformation during CR. However, the addition of 0.5 at% Nb to the alloy changed the SBs’ density and spacing characteristics. The characterization of free volume changes caused by CR was carried out by measuring the density of Archimedes. The micro-hardness of samples was studied by investigating SBs and free volume during plastic deformation. Alloy softening occurred due to the formation of free volume during CR. X-ray photoelectron spectroscopy (XPS) confirmed the presence of oxides ZrO₂, CuO_x, and AlO_x on the surface of the ribbons. The anodic polarization curves of the cast and R50 samples in solutions of NaCl and Na₂SO₄ (0.5 M) were obtained using potentiodynamic polarization measurements. Compared to CR ribbons, melt-spun ribbons after casting showed better corrosion resistance with lower anodic current densities in Na₂SO₄ solution.