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The wear, elastic, mechanical and thermodynamic properties of bulk metallic glasses (BMGs) is studied to explore correlations between the wear resistance and properties of BMGs. It is found that the wear resistance of BMGs is dominated by synergistic effects of strength factors, namely the hardness (H), Young's modulus (E), yield strength (σy) and glass transition temperature (Tg), as well as toughness factors, like the notch toughness (KQ) and Poisson's ratio (ν). Moreover, a novel strategy for optimizing the wear resistance of BMGs is proposed from elastic perspective. The wear resistance of BMGs is correlated with chemistry-induced changes to bulk modulus (B) and Poisson's ratio (ν) for the first time. Developing BMGs with high value of B 0.5 · [ 2 ( 1 + v ) / 3 ( 1 − 2 v ) ] 0.25 can achieve simultaneously both high strength and good toughness, which provides the elastic opportunities for designing ultra-wear-resistant BMGs.

In this study, the influences of Pd, Au and Pt on the glass-forming ability (GFA), mechanical property, electrochemical behavior and tribocorrosion resistance of the Ni- and Cu-free Zr53Al16Co31 bulk metallic glass (BMG) were investigated. Alloying of noble elements enhances the GFA and the Zr53Al16Co26M5 (M = Pd, Au and Pt) BMGs with a diameter of 5 mm can be fabricated by copper mold casting. The ZrAlCo-based BMGs show a good combination of mechanical properties with a high yield strength of over 2000 MPa, low Young's modulus of about 93 GPa and high hardness of over 550 HV. Pd, Au and Pt take a significant influence on the corrosion resistance of the ZrAlCo-based BMGs in phosphate buffer saline (PBS) solution. The ZrAlCoPt alloy exhibits the highest corrosion resistance whereas ZrAlCoAu displays the lowest one, which can be correlated with their Zr and Al concentration in the surface passive film of alloys. The ZrAlCo-based BMGs illustrate a lower wear resistance in PBS solution than that in air, which is attributed to the synergistic effects of abrasive and corrosive wear. The wear resistance of ZrAlCo-based BMGs in PBS solution highly corresponds to their corrosion resistance. The ZrAlCoPt alloy demonstrates the highest tribocorrosion resistance while ZrAlCoAu shows the lowest one among these four ZrAlCo-based BMGs. The possible mechanism of corrosion accelerating wear deterioration is discussed, which provides the guidance for the improvement in the tribocorrosion resistance of Zr-based BMGs for their promising biomedical applications.

The mechanical, electrochemical, wear, and corrosive-wear behaviors of a TiZrCuPd bulk glassy alloy were investigated. The Ti-based glassy alloy demonstrates a high yield strength of 2.3 GPa, low Young's modulus of 95 GPa, and Vickers microhardness of 7.2 GPa, which are superior to those of the Ti-6Al-4V biomedical alloy. The TiZrCuPd glassy alloy shows a good corrosion resistance in the phosphate buffer saline (PBS) solution, owing to the formation the Ti- and Zr-enriched passivation film on the alloy surface. The TiZrCuPd alloy displays the lowdry-wear rate of 6.1 × 10−8 mm3 mm N−1and wet-wear rate of 8.0 × 10−8 mm3 mm N−1. The triobocorrosionresults illustrate that the TiZrCuPd alloyshows a high pitting corrosion resistance during the wet sliding, which render its good corrosive wear performance. The good combination of mechanical, corrosion, and wear properties of the Ti-based glassy alloy make it promising for biomedical applications.

Wear behaviors of the FeCoCrMoCBY bulk metallic glass (BMG), 316 L stainless steel (SS), and CoCrMo alloy under wet sliding in the phosphate buffered saline (PBS) solution were studied and compared with those under dry sliding. The Fe-based BMG exhibited an excellent corrosive wear resistance with a low wear rate of 1.84 × 10−8 mm3 mm−1•N − 1. On the contrary, the CoCrMo alloy and 316 L SS suffered from the synergistic effect of corrosion and wear in the PBS solution. The electrochemical results revealed that the Fe-based BMG possessed the greatest corrosion performance in the PBS solution among three alloys. The excellent corrosion behavior of the Fe-based BMG was attributed to the highly-protective surface passivation film enriched in Cr and Mo elements. The triobocorrosion results manifested that the great anti-corrosive-wear capacity of the Fe-based BMG can be ascribed to the high stable passivation process during wet sliding.

The effects of heat treatment on the microstructures, crystallization kinetics, mechanical performance, and anti-corrosion behavior of a hypoeutectic Zr68Al8Ni8Cu16 bulk metallic glass (BMG) were studied. Through annealing, the precipitated phases were crystalline Zr2Cu and Zr2Ni. The total crystallinity was determined to be 10% and 77% for the samples annealed at 673 K and 713 K, respectively. The partial crystallization of the alloy leads to a dramatic deterioration in the ductility as compared to the as-cast BMG. Furthermore, the decrease in the ductility was accompanied by an increase in the crystallinity. The as-cast Zr-based BMG exhibited a greater corrosion resistance in the HCl solution than that of the annealed alloy. The depletion in the Zr and Al cation fractions of the surface oxidation film, which resulted from the precipitation of reactive nanocrystalline phases from the glassy matrix, is responsible for the reduced corrosion resistance.