Real time optical monitoring to understand railway rail wear and its dependence on steel metallurgy

铁路是未来低碳交通网络的核心，铁路行业一直在寻求创新，以提高整体系统的可靠性。整个轨道系统依赖于轨道本身的质量和性能以及轨道-车轮接触的行为。网络运营商（如Network Rail）一直在寻求创新，以减少维护需求，并减少员工在轨道维护活动中面临的风险。磨损以及滚动接触疲劳裂纹增长是影响钢轨寿命和系统维护需求的主要因素之一。虽然钢轨中裂纹的快速增长是一个主要的安全问题，但磨损通常是一个更明显和渐进的过程，并且在裂纹形成之前去除材料是有益的。然而，磨损导致更换钢轨，并带来经济和环境成本，因此更好地了解其速率和冶金来源有许多好处。这项研究将建立在谢菲尔德大学进行的广泛的轮轨接触研究的基础上，包括最近在英国铁路研究创新网络（UKRRIN）下与英国钢铁公司的合作。这将提供与一批赞助学生合作的机会，并选择与英国钢铁公司密切合作，无论是在我们的联合设备所在的罗瑟勒姆研发设施，还是在我们的斯肯索普制造设施，以满足学生和项目的需求。英国钢铁公司的工作人员与谢菲尔德大学紧密合作，将有定期的联系和合作机会。该项目将利用谢菲尔德大学的世界一流的冶金设施，以及与UKRRIN联合收购的一套铁路专用表征设备。这项工作将利用一种新的光学监测系统来检查双盘摩擦测试的轨道钢在真实的时间，使以前无法获得的研究人员的轨道磨损的角度。计划中的研究包括通过磨损片捕获、显微镜（光学和电子）、机械测试（如硬度和纳米压痕）以及接触和材料建模的实施来表征材料。英国钢铁公司将提供其生产设施作为研发工具，通过控制热处理来生成具有不同原始奥氏体晶粒尺寸和珠光体菌落间距的显微组织。该项目将寻求将磨损行为和磨屑形态的变化与微观结构联系起来。它将联合收割机这种自下而上的微观结构方法与自上而下的监测和建模工作相结合，以提高对磨损的理解，从而指导未来的产品开发和等级选择。

Rail is central to the low carbon transport networks of the future, and the rail industry is constantly looking for innovations to improve overall system reliability. The whole rail system is reliant on the quality and performance of the rails themselves and on the behaviour of the rail-wheel contact. Network operators such as Network Rail are constantly seeking innovations to reduce the requirement for maintenance, and to reduce the exposure of staff to the risks associated with on-track maintenance activities.Wear, alongside rolling contact fatigue crack growth, is one of the major factors influencing rail life and system maintenance requirements. While rapid crack growth in rails is a major safety concern wear is usually a more visible and gradual process, and can be beneficial in removing material prior to crack formation. However, wear leads to rail replacement with economic and environmental costs so there are many benefits to better understanding its rate and metallurgical origin. This research will build on the extensive body of wheel-rail contact research carried out at the University of Sheffield, including the recent collaboration with British Steel under the UK Rail Research Innovation Network (UKRRIN). This will offer the opportunity to work with a cohort of sponsored students and options to work closely with British Steel either at our Rotherham R&D facility where joint equipment is located, or at our manufacturing facility in Scunthorpe as suits student and project needs. British Steel staff are closely integrated with the University and there will be regular contact and opportunities to work collaboratively.This project will make use of the world-class metallurgical facilities at The University of Sheffield, in addition to the suite of rail-specific characterization equipment jointly acquired under UKRRIN. The work will make use of a novel optical monitoring system to examine twin disc tribological testing of rail steels in real time, enabling a perspective of rail wear previously unavailable to researchers. Planned research includes materials characterization via wear flake capture, microscopy (optical and electron), mechanical testing such as hardness and nanoindentation, and implementation of contact and materials modelling.British Steel will provide access to their production facilities as an R&D tool, enabling the generation of microstructures with varied prior austenite grain size and pearlite colony spacing via controlled heat treatment. The project will seek to correlate variations in wear behaviour and wear flake morphology with microstructure. It will combine this bottom-up microstructural approach with the top-down monitoring and modelling work to generate an improved understanding of wear that can guide future product development and grade selection.