Understanding intermediate temperature fatigue crack growth in single crystal Ni-based superalloys

罗尔斯·罗伊斯公司正在赞助一项为期四年的工业案例奖，致力于一系列航空发动机涡轮机叶片系统的基本疲劳失效研究。了解控制涡轮机叶片中的疲劳过程、裂纹率和裂纹路径的因素对于未来的叶片设计以及当前的检查和修复方法都非常重要。这些涡轮机叶片材料通常在航空发动机中经历一定范围的工作温度、负载和环境条件。这些测试参数在单晶镍基高温合金涡轮机叶片部件中的相互作用提供了一组有趣的复杂服务故障，需要详细的调查和解释。博士将专注于了解这些复杂的裂解过程是如何发生的，以及是什么控制着这些过程。我们的测试结构研究实验室（TSRL）的先进机械测试能力将用于在一系列测试环境中进行高温混合模式加载疲劳测试。测试后的断口分析将包括扫描电子显微镜和使用X射线CT在我们最先进的X射线断层扫描中心（mVIS）中评估3D裂纹尖端过程，该中心也是X射线成像国家研究设施的一部分。

Rolls Royce are sponsoring an Industrial CASE award for four years, working on fundamental fatigue failure investigations in a range of aeroengine turbine blade systems. Understanding what controls the fatigue processes, cracking rates and the crack paths taken in turbine blades is extremely important in both future blade design, but also in informing current inspection and repair approaches. These turbine blade materials typically experience a range of service temperatures, loads and environmental conditions in the aeroengine. The interplay of these testing parameters in the single crystal nickel base superalloy turbine blade components offers a fascinating set of complex service failures that need detailed investigation and explanation. The PhD will focus on understanding how these complex cracking processes occur, and what controls these processes. Advanced mechanical testing capabilities in our testing structures research laboratory (TSRL) will be used to conduct high temperature mixed mode loading fatigue tests in a range of testing environments. Post-test fractographic analysis will include scanning electron microscopy and the use of X-ray CT to evaluate crack tip processes in 3D in our state-of-the-art X-ray tomography centre (mVIS) which is also part of the National Research Facility in X-ray imaging.