Composition design and first-principles calculations of (ZrTiHfNi)100-xNbx high-entropy amorphous alloys

High-entropy amorphous alloys exhibit outstanding performance and immense application potential due to their unique long-range disordered structure and multi-principal-element characteristics. Glass-forming ability (GFA) is crucial in determining their performance and manufacturability. This study designed a (ZrTiHfNi) 100-x Nb x high-entropy amorphous alloy system based on key physicochemical parameters, followed by a systematic investigation combining first-principles molecular dynamics simulations with experimental validation. The results reveal that Nb addition significantly alters interatomic interactions and local packing. At 15 at.% Nb, the system exhibits optimal structural characteristics: the shortest average bond length, the highest coordination number, and the greatest fraction of icosahedral clusters, indicating the densest local packing and most stable short-range order. TEM and XRD experimental results indicate that all composition bands exhibit typical amorphous structures, with the XRD diffraction peaks of the Nb15 composition displaying the largest full width at half maximum (FWHM). This work clarifies the atomic-scale mechanism behind the composition-dependent GFA in this system.