Influence of Integrated HIP Heat Treatments on the Microstructure and Mechanical Properties of a PM Tool Steel: Experiment and Simulation

申请人以前的研究活动，包括DFG资助的研究项目，研究了压力对几种金属合金体系微观结构演变的影响。通过建立在先验知识的基础上，该项目旨在揭示和利用与热等静压高合金工具钢的热处理相关的工艺-结构-性能关系。这些复杂的多相材料由于其技术轴承和潜在的微观和宏观热机械性能而特别有趣。通过生成目标微观结构状态并通过图像分析和立体技术调查它们，将研究过程结构联系。另一方面，结构-性能关系将通过广泛的力学测试来揭示。这些努力的核心是最先进的实验室设备：一种新型的均匀快速淬火热等静压机，能够部署复杂的温度和压力剖面，将在集成的固化-热处理过程中设置目标微观结构。扫描和透射电子显微镜将提供所需的分辨率来识别和描述当前的微观结构演变。此外，还将研究所选微观组织状态的循环和准静态力学性能。其中包括高分辨率的测试和表征方法，这些方法揭示了否则无法检测到的微观结构特征，并允许分析微观结构和性能之间的相关性。热力学模拟将支持这一实验发现工作，提供对活性机制的更深入了解，同时提供一种追求微观结构设计的手段。

Previous research activities by the applicants, including research projects funded by the DFG, investigated the effects of pressure on the microstructural evolution of several metallic alloy systems. By building upon prior knowledge, this project aims to uncover and utilize the process-structure-property relationships associated with heat treatments integrated into hot isostatic pressing of high-alloy tool steels. These complex multiphase materials are particularly interesting as a subject matter because of their technological bearing and underlying micro and macro thermomechanical properties. Process-structure links will be studied by generating targeted microstructural states and investigating them through image anaylsis and stereological techniques. Structure-property relationships, on the other hand, will be uncovered by extensive mechanical testing. At the heart of these efforts is state-of-the-art laboratory equipment: A novel uniform rapid quenching hot isostatic press, capable of deploying complex temperature and pressure profiles, will set the target microstructures in an integrated consolidation-heat treatment process. Scanning and transmission electron microscopy will provide the required resolution to identify and describe the present microstructural evolutions. In addition, cyclic and quasi-static mechanical properties of selected microstructural states will be investigated. These include high-resolution testing and characterization methods that reveal otherwise undetectable microstructural features and allow analysis of the correlation between microstructure and properties. Thermokinetic simulations will support this experimental discovery effort to provide deeper insights into the active mechanisms while delivering a means to pursue microstructure design.