Tribological properties of Zr41.25Ti13.75Ni10Cu12.5Be22.5 bulk metallic glasses under different conditions

Due to the unique properties of bulk metallic glasses (BMGs), BMGs have widely been used in mechanical engineering components. Although their materials design and mechanical properties have been thoroughly investigated, knowledge of their tribological behaviors is still rather lacking. Block-on-disc tests were thus conducted to investigate the friction and wear behaviors of Zr41.25Ti13.75Ni10Cu12.5Be22.5 BMGs when slid correspondingly: (i) under dry condition, (ii) in deionized water, and (iii) in solution respectively with 30%, 60% and 90% hydrogen peroxide. Results demonstrated that their friction coefficient was: (i) the lowest when slid under dry condition, and (ii) the highest when slid in 60% hydrogen peroxide solution. Moreover their best wear resistance was when slid under the dry condition and the worst when slid in the 30% hydrogen peroxide solution. Analysis of the worn surface revealed that the sliding wear mechanism of BMGs was mainly inhomogeneous plastic deformation, abrasive wear, adhesive wear, micro-cutting, oxidative wear, and peeling-off, and it changed with the change in sliding environment.

► The results indicated that environment conditions significantly affect the tribological behaviors of Zr-based bulk metallic glasses. The friction coefficient was the lowest under dry sliding and the highest in 60% hydrogen peroxide, while the wear resistance of Zr-based bulk metallic glasses was the best test under dry condition, followed by the alloy under 90% hydrogen peroxide, 60% hydrogen peroxide, and deionized water, worst wear was observed under 30% hydrogen peroxide.
► The weight of discs increased under dry sliding, and deionized water, it decreased under hydrogen peroxide with different concentrations.
► Zr-based bulk metallic glasses exhibits mainly micro-cutting, abrasive wear and peeling-off wear with some of the oxidative wear manner when the pairs under hydrogen peroxide with different concentration, the wear mechanism may change with the environment alteration.