Fundamental multiscale investigations for improved calculation of the service life of solid lubricated rolling bearings

改进固体润滑滚动轴承使用寿命计算的基础多尺度研究

• 批准号: 407707942
• 负责人: Professor Dr.-Ing. Benoit Merle
• 金额: --
• 依托单位: Computer-Chemie-Centrum (CCC)
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/407707942?language=en
• 关键词: Fundamental; multiscale; investigations; improved; calculation

The project aims at gathering the fundamental knowledge required for improving the calculation of the service life of solid lubricated rolling bearings, which are typically used in vacuum pumps and rotating anodes of medical X-Ray devices. The project will specifically focus on MoS2 tribological coatings. The only service life calculation model available up to date relies on an empirical approach, based on the assessment of the wear rate from macroscopic contact parameters such as load and sliding distance. This model does not capture important processes, such as the progressive transfer and redeposition of coating material onto the uncoated counterpart. The proposed investigations will enable the development of a mechanistic model taking into account the influence of the microstructure, texture and stoichiometry of the coating and relying only marginally on empirical parameters. The primary challenge consists into identifying the fundamental mechanisms governing the deformation of the coating during rolling contact and understanding the consequences in term of material removal, as well as its transfer and deposition onto the uncoated counterpart. This goal will be met by implementing a multi-scale approach closely combining experimental characterizations with computer simulations. The investigations will focus on two different MoS2 PVD coatings: the first one featuring a strongly basal texture associated with a coarse microstructure and the second one a weak texture associated with a fine columnar microstructure. The tribological behavior of these coatings will be investigated at the macroscopic scale by twin-disc tests performed under realistic service conditions. Interrupted monitoring by electron microscopy and atom probe tomography will allow assessing the structural and crystallographic evolution of the coating at the micro and nanoscale as a function of the loading duration. Micromechanical testing will furthermore provide direct insights into the associated deformation and material removal processes. The underlying fundamental mechanisms will finally be revealed by atomistic simulations. As these account for the observed transformation of the coating, they are ultimately responsible for its lifetime, which implies that their knowledge will enable formulating a mechanistic model for the service life prediction of MoS2 solid lubricated rolling bearings.

该项目旨在收集改善固体润滑滚动轴承使用寿命计算所需的基础知识，固体润滑滚动轴承通常用于真空泵和医用x射线设备的旋转阳极。该项目将特别关注二硫化钼摩擦学涂层。目前唯一可用的使用寿命计算模型依赖于经验方法，该方法基于宏观接触参数（如载荷和滑动距离）对磨损率的评估。该模型没有捕捉到重要的过程，如涂层材料的逐步转移和再沉积到未涂层的对应物上。所提出的研究将使一个考虑到涂层的微观结构、质地和化学计量的影响的机制模型的发展成为可能，并且只略微依赖于经验参数。主要的挑战在于确定在滚动接触过程中控制涂层变形的基本机制，并了解材料去除的后果，以及其转移和沉积到未涂层的对应物上。这一目标将通过实施多尺度方法紧密结合实验表征和计算机模拟来实现。研究将集中在两种不同的MoS2 PVD涂层上：第一种涂层具有强烈的基底织构，具有粗糙的微观结构；第二种涂层具有弱织构，具有细柱状微观结构。这些涂层的摩擦学性能将通过在实际使用条件下进行的双盘试验在宏观尺度上进行研究。通过电子显微镜和原子探针断层扫描的间断监测，可以评估涂层在微观和纳米尺度上的结构和晶体学演变，作为加载时间的函数。微观力学测试将进一步提供对相关变形和材料去除过程的直接见解。潜在的基本机制将最终通过原子模拟揭示出来。由于这些解释了观察到的涂层转变，它们最终对其寿命负责，这意味着它们的知识将能够制定MoS2固体润滑滚动轴承使用寿命预测的机制模型。