The load-bearing behaviour of lubricated contacts depends primarily on the normal force, the relative velocity, and the geometry. Thus, with the aid of the Stribeck curve, it is usually well possible to characterize whether hydrodynamics, mixed friction, or boundary friction is more likely to be present. The fact that the load regime can also depend on the fluid quantity is obvious, but has hardly been systematically investigated so far. Especially for contacts with microscopic roughness, the defined application of a very small amount of fluid is a very challenging requirement. In this paper, a very fundamental study shows how a pin-on-disc tribometer can be used to achieve the transition from dry friction via mixed friction to predominant hydrodynamics by the amount of supplied fluid. The experiments are carried out on samples filed with different coarseness. In addition, the simultaneous influence of partial filling and normal force as well as relative velocity is also shown. Very good reproducibility has been practically reached over the entire range of the tests. Regarding the quantities for the coefficient of friction (COF), it was concluded that close to full filling, a reduction of the fluid quantity has a similar effect on the COF as the reduction of the velocity. This property goes along with the common theory of starved lubricated systems. Such behaviour was not observed to the same extent for the normal force. In the vicinity of smaller fluid quantities, the COF increases very rapidly with further reduction in fluid quantity, far more disproportionately than that with reduction in velocity. With a deeper understanding of this problem, various practical issues such as idling or the run-up process in bearings can also be studied in a more focused manner.

润滑触点的承载行为主要取决于法向力、相对速度和几何形状。因此，借助 Stribeck 曲线，通常可以很好地表征流体动力学、混合摩擦或边界摩擦是否更可能存在。负载状态也取决于流体量这一事实是显而易见的，但迄今为止几乎没有系统地研究过。特别是对于具有微观粗糙度的触点，极少量流体的定义应用是一项非常具有挑战性的要求。在本文中，一项非常基础的研究显示了如何使用销盘式摩擦计实现从通过混合摩擦的干摩擦到通过供应流体量的主要流体动力学的转变。实验是在不同粗糙度的样品上进行的。此外，还显示了部分填充和法向力以及相对速度的同时影响。在整个测试范围内实际上都达到了非常好的重现性。关于摩擦系数 (COF) 的量，得出的结论是，接近完全填充时，流体量的减少对 COF 的影响与速度的降低类似。这一特性与缺乏润滑系统的共同理论相一致。对于法向力，没有以相同程度观察到这种行为。在较小的流体量附近，随着流体量的进一步减少，COF 会非常迅速地增加，远不成比例地随着速度的减少而增加。