The shaft mechanical face seal in a high-speed turbopump of a liquid rocket engine often operates under extremely harsh conditions. For example, a low-temperature and low-viscosity fluid (such as liquid oxygen or liquid hydrogen) is used as a lubricant. The performance of the seal rings, especially the friction and wear behavior, directly determines whether the seal functions normal. In this study, the friction and wear behavior of several ring materials are tested using a pin-on-disk tribo-tester, and the wear morphology of the ring is investigated. The friction coefficients (COFs) and mass-wear rates under dry-friction and water-lubricated conditions, which are used to simulate low-viscosity conditions, are obtained. The results show that at a pressure-velocity (PV) value of 2.4 MPa·(m/s), the COF between the copper graphite (stator) and copper-chrome alloy disk (rotor) is low (with a value of 0.18) under the dry-friction conditions, and the 5-min wear mass of the copper graphite is approximately 2 mg. Under the water-lubricated conditions, compared with other materials (such as copper-chrome alloy, S07 steel, alumina ceramic coating, and nickel-based calcium fluoride), the S07 steel with a diamond-like carbon film is preferred for use in a high-speed turbopump under extreme conditions. The results of this study can provide theoretical and experimental guidance in the design of mechanical face seals in liquid rocket engines.

液体火箭发动机的高速涡轮泵中的轴机械端面密封通常在极其恶劣的条件下运行。例如，将低温低粘度的流体（例如液氧或液氢）用作润滑剂。密封环的性能，尤其是摩擦和磨损行为，直接决定了密封是否正常工作。在这项研究中，使用销盘摩擦式测试仪测试了几种环材料的摩擦和磨损行为，并研究了环的磨损形态。获得了用于模拟低粘度条件的干摩擦和水润滑条件下的摩擦系数（COFs）和整体磨损率。结果表明，在压力速度（PV）值为2.4 MPa·（m / s）时，在干摩擦条件下，铜石墨（定子）和铜铬合金盘（转子）之间的COF低（值为0.18），并且铜石墨的5分钟磨损质量约为2 mg。在水润滑条件下，与其他材料（例如铜铬合金，S07钢，氧化铝陶瓷涂层和镍基氟化钙）相比，具有钻石状碳膜的S07钢更适合用于极端条件下的高速涡轮泵。这项研究的结果可以为液体火箭发动机的机械端面密封设计提供理论和实验指导。与其他材料（例如铜铬合金，S07钢，氧化铝陶瓷涂层和镍基氟化钙）相比，带有类金刚石碳膜的S07钢更适合在极端条件下用于高速涡轮泵。这项研究的结果可以为液体火箭发动机的机械端面密封设计提供理论和实验指导。与其他材料（例如铜铬合金，S07钢，氧化铝陶瓷涂层和镍基氟化钙）相比，带有类金刚石碳膜的S07钢更适合在极端条件下用于高速涡轮泵。这项研究的结果可以为液体火箭发动机的机械端面密封设计提供理论和实验指导。