Bonding and elastic properties of amorphous AlYB14

• Bonding and elasticity of amorphous AlYB14 were probed.
• Ab initio data imply icosahedral bonding and large stiffness.
• Thin films were synthesized by magnetron sputtering.
• The theoretical predictions were verified experimentally.
• This model provides a foundation for knowledge-based design of amorphous solids.

We have studied the bonding and elastic properties of amorphous AlYB14 using theoretical and experimental means. Based on pair distribution functions and Voronoi tessellation, the icosahedral bonding is expected. A rather large Young's modulus of 365 GPa is predicted for amorphous AlYB14. To verify these predictions, we have measured density, pair distribution functions, binding energy and elastic properties of Al–Y–B thin films synthesized by magnetron sputtering. The calculated and measured densities are with a deviation of 3.5% in good agreement. The measured binding energy and pair distribution functions are also consistent with icosahedral bonding. The measured Young's modulus is 305±19 GPa, which is 16% smaller than the theoretical value and hence in good agreement. Overall consistency between theory and experiments was obtained indicating that the computational strategy employed here is useful to describe correlations between bonding, elasticity, density as well as (chemical) short range order and may hence enable future knowledge-based design of these ternary borides which show great potential for surface protection applications.