It has been recently demonstrated that the superlubricity behavior of polyalkylene glycol (PAG) aqueous solutions can be achieved in a wide variety of applied conditions. However, certain parameters are expected to be adjusted further to achieve a more controllable superlubricity system. Herein, it is demonstrated that an ultralow friction coefficient can be obtained by concentrated PAG aqueous solutions (80 wt% HB‐260) as the contact pressure becomes relatively low (37 MPa). Meanwhile, the superlubricity state can be adjusted in a timely manner by adjusting the relative sliding speed. Here, the viscosity of the PAG aqueous solution (determined by its concentration and molecular weight) and applied conditions, including contact pressure and relative sliding speed, are considered as critical parameters influencing the lubricating performance. According to the theoretical analysis, the superlubricity state is confirmed and a fitted superlubricity region is proposed, which provides a comprehensive guide for achieving controllable superlubricity in the future.

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各种应用条件下聚亚烷基二醇水溶液的可控超润滑系统

最近已经证明，可以在各种应用条件下实现聚亚烷基二醇（PAG）水溶液的超润滑性能。然而，期望某些参数将被进一步调节以获得更可控的超润滑系统。本文证明，当接触压力变得相对较低（37 MPa）时，通过浓缩PAG水溶液（80 wt％HB-260）可以获得超低摩擦系数。同时，可以通过调节相对滑动速度来及时调节超润滑状态。在此，PAG水溶液的粘度（由其浓度和分子量决定）和所施加的条件，包括接触压力和相对滑动速度，被认为是影响润滑性能的关键参数。