Friction reduction in lubricated tribological contacts by micro textured surfaces

通过微纹理表面减少润滑摩擦接触中的摩擦

• 批准号: 426217784
• 负责人: Professorin Dr.-Ing. Marion Merklein
• 金额: --
• 依托单位: Lehrstuhl für Fertigungstechnologie (LFT)
• 依托单位国家: 德国
• 项目类别: Research Grants (Transfer Project)
• 财政年份: 2020
• 资助国家: 德国
• 起止时间: 2019-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/426217784?language=en
• 关键词: Friction; reduction; lubricated; tribological; contacts

The modification of component surfaces in lubricated tribological systems can improve the tribological behavior and reduce friction losses. This can be achieved by tribological layers or by discrete microtextures applied to the component surface. With regard to larger quantities, these microtextures have to be realized by forming processes such as micro coining, which can be integrated into conventional manufacturing processes. Up to now, basic knowledge is missing in order to understand the manufacturing challenges in combined forming processes during component production. In addition, a deeper understanding of the effects as well as the optimal design of surface microtextures in lubricated tribological contacts is lacking.The aim of the research project is to gain basic scientific knowledge with regard to the effect of surface microtextures in EHL contacts, as well as their manufacturability using forming processes. In cooperation with industrial partners, the obtained basic knowledge is transferred to industrial applications. A more realistic determination of the effects of microtextures in rolling-sliding contacts is achieved by the expansion of a TEHL simulation model by the influence of thin layers, roughness and solid-solid contact as well as dynamic operating conditions. Exemplary for the cam/tappet-contact, over the cup surface locally optimized microtextures are derived, taking into account the manufacturing limitations. Latter are investigated for an extrusion-coining process, in which a more homogeneous and precise texture shaping on the component by an inverse texture optimization is strived. In addition, a combined process including deep drawing, ironing and coining which has a lower material flow in the coining area is compared with the extrusion process. The objective is to identify process-specific influencing variables on the texture shape. In addition, the wear behavior of the coining punches is examined using a wear test-rig. The overriding objective of the study is to gain knowledge on the achievable accuracy of the texture geometry as well as on the application behavior of the tools based on numerical models and simplified bench tests. The analysis of the application behavior of the components in terms of friction and wear in a complete test chain from model, over component, to aggregate testing-rigs serves to validate the numerical design. Finally, the obtained knowledge about suitable and simultaneously technically feasible microtextures is validated for different application cases using experimental setups.

对润滑摩擦系统中的构件表面进行改性处理，可以改善摩擦学性能，降低摩擦损失。这可以通过摩擦层或通过施加到部件表面的离散微纹理来实现。对于更大的数量，这些微纹理必须通过成形工艺实现，例如微压印，其可以集成到传统的制造工艺中。到目前为止，基本知识是缺失的，以了解在组件生产过程中组合成形工艺的制造挑战。此外，对润滑摩擦接触中表面微织构的影响以及优化设计缺乏更深入的了解，本研究项目的目的是获得关于EHL接触中表面微织构影响的基础科学知识，以及它们使用成形工艺的可制造性。通过与工业合作伙伴的合作，将获得的基础知识转移到工业应用中。一个更现实的确定在滚动-滑动接触的微观织构的影响，实现了由薄层，粗糙度和固-固接触以及动态操作条件的影响的TEHL模拟模型的扩展。示例性的凸轮/挺杆接触，在杯表面上的局部优化的微观纹理的推导，考虑到制造的限制。后者是针对挤压-压印工艺进行研究的，其中通过逆纹理优化来努力在部件上形成更均匀、更精确的纹理。此外，还将拉深、变薄和精压的复合工艺与挤压工艺进行了比较，结果表明，复合工艺在精压区的材料流动较小。其目的是确定特定工艺的纹理形状的影响变量。此外，使用磨损试验台检查压印冲头的磨损行为。这项研究的首要目标是获得知识的纹理几何形状的可实现的精度，以及基于数值模型和简化的台架试验的工具的应用行为。在从模型到组件再到集料试验台的完整试验链中，对组件在摩擦和磨损方面的应用行为进行分析，以验证数值设计。最后，所获得的知识，适当的，同时技术上可行的显微纹理验证不同的应用情况下，使用实验装置。