Intermetallic γ-TiAl-based alloys are commonly used as structural materials for components in high-temperature applications, although they generally suffer from a lack of ductility and crack resistance at ambient temperatures. Within this study, the process-adapted 4th generation TNM+ alloy, exhibiting a fully lamellar microstructure, was examined using notched micro-cantilevers with defined orientations of lamellar interfaces. These configurations were tested in situ using superimposed continuous stiffness measurement methods during loading with simultaneous scanning electron microscopy observations. Subsequently, the video signal was used for visual crack length determination by computer vision and compared to values calculated from in situ changes in stiffness data. Applying this combinatorial approach enabled to determine the J-integral as a measure of the fracture toughness for microstructurally different local crack propagation paths. Thus, distinct differences in conditional fracture toughness could be determined from 3.7 MPa m1/2 for γ/γ-interface to 4.4 MPa m1/2 for α2/γ-interface.

尽管基于金属间化合物的γ-TiAl基合金通常在环境温度下缺乏延展性和抗裂性，但它们通常用作高温应用中构件的结构材料。在这项研究中，使用带有已定义的层状界面取向的带缺口的微悬臂梁，检查了适应工艺的第四代TNM +合金，其展现出完整的层状微观结构。在同时加载扫描电子显微镜观察的过程中，使用叠加连续刚度测量方法对这些配置进行了现场测试。随后，将视频信号用于通过计算机视觉确定视觉裂缝长度，并将其与从原位计算出的值进行比较刚度数据的变化。应用这种组合方法能够确定J积分，作为微观结构不同的局部裂纹扩展路径的断裂韧性度量。因此，在条件断裂韧性明显的差异可确定从3.7兆帕米1/2为γ/γ-接口至4.4兆帕米1/2为α 2 /γ-接口。