Thanks to their outstanding mechanical properties, Bulk Metallic Glasses (BMGs) are new alternatives to traditional crystalline metals for mechanical and micromechanical applications including power transmission. However, the tribological properties of BMGs are still poorly understood, mostly because their amorphous nature induces counter intuitive responses to friction and wear. In the present study, four different BMGs (Cu₄₇Zr₄₆Al₇, Zr₄₆Cu₄₅Al₇Nb₂, Zr₆₀Cu₂₈Al₁₂, and Zr₆₁Cu₂₅Al₁₂Ti₂) underwent ball-on-disc friction tests against 100Cr6 steel balls (American Iron and Steel Institute (AISI) 52100) at different relative humidities (RHs) ranging from 20% to 80%. Controlling humidity enabled to observe a high repeatability of the friction and wear responses of the BMG. Interestingly, the friction coefficient decreased by a factor of 2 when the humidity was increased, and the wear rate of BMGs was particularly low thanks to a 3rd-body tribolayer that forms on the BMG surface, composed of oxidized wear particles originating from the ball. The morphology of this tribolayer is highly correlated to humidity. The study also identifies how the tribolayer is built up from the initial contact until the steady state is achieved.

由于其出色的机械性能，大块金属玻璃 (BMG) 是传统结晶金属的新替代品，适用于包括电力传输在内的机械和微机械应用。然而，BMG 的摩擦学特性仍然知之甚少，主要是因为它们的无定形性质会导致对摩擦和磨损的反直觉反应。在本研究中，四种不同的 BMG（Cu ₄₇ Zr ₄₆ Al ₇、Zr ₄₆ Cu ₄₅ Al ₇ Nb ₂、Zr ₆₀ Cu ₂₈ Al ₁₂和 Zr ₆₁ Cu ₂₅ Al ₁₂ Ti ₂) 在 20% 至 80% 的不同相对湿度 (RH) 下对 100Cr6 钢球（美国钢铁协会 (AISI) 52100）进行了球盘摩擦试验。控制湿度能够观察到 BMG 的摩擦和磨损响应的高重复性。有趣的是，当湿度增加时，摩擦系数降低了 2 倍，并且 BMG 的磨损率特别低，这要归功于 BMG 表面形成的第三体摩擦层，该摩擦层由源自球的氧化磨损颗粒组成。该摩擦层的形态与湿度高度相关。该研究还确定了从初始接触到达到稳定状态，摩擦层是如何形成的。