EAGER/DMREF: In-Situ Thermomechanical Processing and Measurement in the Scanning Electron Microscope

提高工程合金的性能有很多应用，但在这一领域的创新需要在微观尺度上对这些材料的行为有精确的了解。这项早期概念探索性研究(EAGER)/设计材料以革新和设计我们的未来（DMREF）奖支持加速优化工程合金加工方法的努力。一个“微型模拟器”将在电子显微镜内建立，以复制金属合金在从原材料到成品的加工过程中所经历的温度和应力。该设备将提供在加工过程中对材料的详细内部结构进行成像的能力。测量材料机械性能的仪器也将集成到该系统中。这种能力的组合将提供前所未有的能力，将加工条件与材料的结构和性能相关联，并有助于有效地确定改进的加工条件，以提高性能。参与该项目的研究生将接受设计和建造复杂仪器的培训，这是国家技术竞争力的关键技能。本研究的主要目标是在扫描电子显微镜下实现相关的热机械加工和测量条件，实现金属合金热机械实时加工过程中应力和温度条件与微观组织演变和力学性能的相关性。将开发一个自适应微尺度模拟器，该模拟器将在显微镜内运行，并集成在商业金属合金加工相关条件下加热和应力样品的能力，并结合使用集成纳米压头测量局部机械性能的能力。该仪器将允许进入该系统中包含相和微观结构演变的温度范围，以及接近或超过屈服应力的拉伸应力的应用，同时以纳米级分辨率成像。此外，集成纳米压头的设计使局部微观结构与力学性能相关联。这种独特的功能组合将为热机械加工条件下不断变化的微观结构和性能提供广泛的新见解。

Improving the performance of engineering alloys has a great many applications, but innovation in this area requires precise knowledge of the behavior of these materials at the microscopic scale. This EArly-concept Grant for Exploratory Research (EAGER)/Designing Materials to Revolutionize and Engineer our Future (DMREF) award supports efforts to accelerate the optimization of processing methods for engineering alloys. A "micro-simulator" will be built within an electron microscope to replicate the temperatures and stresses that a metallic alloy experiences during the processing steps from raw materials to a manufactured form. This device will provide the ability to image the detailed internal structure of the material as it is processed. An instrument for measuring the mechanical properties of the material will also be integrated into the system. This combination of capabilities will provide unprecedented ability to correlate processing conditions to the structure and properties of the material, and help efficiently identify improved processing conditions for improved performance. The graduate students involved in this project will receive training in designing and building complex instrumentation, a key skill for national technological competitiveness.The primary goal of this research is to implement relevant thermo-mechanical processing and measurement conditions within a scanning electron microscope, to enable correlation of stress and temperature conditions to microstructural evolution and mechanical properties during real time thermo-mechanical processing of metal alloys. An Adaptive Microscale Simulator will be developed that will operate within the microscope and integrate the ability to heat and stress samples under conditions relevant to commercial metal alloy processing, combined with the ability to measure local mechanical properties using an integrated nano-indenter. The instrumentation will allow access to the range of temperatures that encompass phase and microstructural evolution in this system, and application of tensile stresses that approach or exceed the yield stress, while imaging at nanometer-scale resolution. Further the integrated nano-indenter is designed to correlate local microstructure to mechanical properties. This unique combination of capabilities will provide broad new insight into evolving microstructure and properties under thermo-mechanical processing conditions.