Although the efficiency of a gear pair is currently high, a better understanding of surface/lubricant contribution on efficiency is critical. Electrified drivelines will, for example, impose higher speed and alternate loading, and it is expected that these new conditions will, to a greater extent, rely on the surface/lubricant characteristics. Phenomena taking place in the gear contact is often measured using ball-on-disc and twin-disc tribometers. In this study, these two test set-ups were compared in order to assess differences in the behaviour of surface/lubricant interactions. Results showed that ball-on-disc and twin-disc set-ups reflect the same friction trends. However, the friction results differed by a factor of roughly two, even though the tribometers were set-up to run at the same contact pressure. The wear mechanisms also differed: micropits occurred on discs used in the twin-disc set-up, whereas normal or no wear was found on the ball-on-disc specimens. The contact conditions for the two test set-ups were also analysed using a numerical model. The comparison of these two machines may aid gear designers in selecting the proper experimental set-up for their purpose.

中文翻译：

---

滚动/滑动触点摩擦表面粗糙度的研究：圆盘球与双盘

尽管目前齿轮对的效率很高，但更好地了解表面/润滑剂对效率的作用至关重要。电气传动系统将例如施加更高的速度和交替负载，并且可以预期，这些新条件将在更大程度上依赖于表面/润滑剂特性。齿轮接触中发生的现象通常使用圆盘球和双盘摩擦计测量。在这项研究中，比较了这两个测试设置，以评估表面/润滑剂相互作用的行为差异。结果表明，圆盘和双盘设置反映了相同的摩擦趋势。但是，即使将摩擦计设置为在相同的接触压力下运行，摩擦结果也相差大约两倍。磨损机理也有所不同：在双碟片装置中使用的碟片上会出现微坑，而在圆盘碟片标本上发现正常或无磨损。还使用数值模型分析了两个测试装置的接触条件。这两台机器的比较可以帮助齿轮设计者选择合适的实验装置。