Electron tomography (ET) has been introduced in materials science in the past decade and it has opened a new prospect: the technique can retrieve three-dimensional (3D) structural information [1]. However, a major roadblock exists to combine the in-situ experiments with electron tomography, which is expected to reveal real time 3D structural changes [2]. Towards dynamic 3D (i.e., “4D-ET”) visualization of material’s microstructures under various straining conditions with a time scale of a few minutes or less, we designed and developed a new specimen holder compatible with tensile test and high-angle tilting, termed as “straining and tomography (SATO)” holder [3].
Figure 1 shows a schematic illustration of a newly designed specimen holder (a) and a cartridge-type blade on which a specimen is glued (b). The area of gluing is marked by gray. The basic concept of this development is a single tilt-axis holder with a tensile mechanism and also being capable of electron tomography. To achieve straining and high-angle tilting simultaneously, we developed a novel mechanism as shown in Fig. 1(a). A linear motion actuator deforms a newly designed cartridge-type blade on which a specimen is glued. Deformation velocity of the blade is designed as 1/3 of that of the actuator. Figure 1(b) explains the motion of blade. The trajectory (dotted line) is an arc but the radius of curvature (R) is so large (3 mm) that the tensile axis is perpendicular to the holder for a nanometer- scale object whose center is located at O.
Figure 2 shows (a) an appearance of the developed specimen holder and (b) a magnified photo of the cartridge-type blade. The holder motion is fully computer-controlled via graphical user interface developed for this system. We measured the deformation velocity of the blade and deduced the strain rate. The minimum and the maximum values obtained were 1.5×10-6 and 5.2×10-3 s-1. The blade as well as the holder is robust and multiple acquisitions raise no technical problem at all. This result demonstrates stability and reliability of the holder as a novel in-situ experimental instrument for 4D-ET. We also confirmed that the maximum tilt angle of the specimen holder reaches ±60o with a rectangular shape aluminum specimen.
Figure 3 shows an example of in-situ tensile test using the newly developed holder. The material is an Al-Mg-Si alloy with a conventional 3 mm diameter disk shape prepared by electropolishing (Fig. 3(a)). When the actuator moved 9.87 μm from the initial position, slip bands were suddenly introduced (Fig. 3(b)). With increasing the tensile stress, slip bands were discontinuously but incrementally introduced in several parts of the field of view until a crack was introduced elsewhere. It should be mentioned that the drift of a field of view was negligible throughout the in-situ tensile experiment. The new specimen holder will have wide range potential applications in materials science.
References
[1] S. Hata, H. Miyazaki, S. Miyazaki et al., Ultramicrosc. 111, 1168 (2011).
[2] J. Kacher, G. S. Liu, and I. M. Robertson, Micron 43, 1099 (2012).
[3] K. Sato, H. Miyazaki, T. Gondo, S. Miyazaki, M. Murayama and S. Hata, Microscopy 64, 369 (2015).
[4] This study was supported by the Grant-in-Aid for Scientific Research on Innovative Area, “Bulk Nanostructured Metals” (Grant No. 25102703) from the Ministry of Education, Culture, Sports, Science and Technology, Japan. K. S. and S. H. acknowledge the financial support from the Japan Science Technology Agency (JST) “Development of systems and technology for advanced measurement and analysis” program.
Figures:
Figure 1. (a) A schematic illustration of a newly designed specimen holder and (b) a cartridge-type blade on which a specimen is glued.
Figure 2. (a) An appearance of a developed specimen holder and (b) a magnified photo of a cartridge-type blade.
Figure 3. An example of in-situ tensile test using the newly developed holder. The material is an Al-Mg-Si alloy with a conventional 3 mm diameter disk shape. (a) An early stage of straining, (b) slip bands suddenly appeared.
To cite this abstract:
Kazuhisa Sato, Hiroya Miyazaki, Takashi Gondo, Shinsuke Miyazaki, Mitsuhiro Murayama, Satoshi Hata; Development of a novel straining holder for TEM compatible with electron tomography. The 16th European Microscopy Congress, Lyon, France. https://emc-proceedings.com/abstract/development-of-a-novel-straining-holder-for-tem-compatible-with-electron-tomography/. Accessed: September 21, 2023« Back to The 16th European Microscopy Congress 2016
EMC Abstracts - https://emc-proceedings.com/abstract/development-of-a-novel-straining-holder-for-tem-compatible-with-electron-tomography/