题目：Recent Innovation in Small Scale In-Situ Mechanical Properties Testing

报告人：Viola Paul, Alemnis AG, Switzerland

时间：2025年7月9日（周三）上午9:00

地点：李薰楼249室

摘要：

In situ SEM micro- and nanomechanical testing is an indispensable technique for materials design as well as for fundamental mechanics research. Many new protocols and testing geometries beyond traditional nanoindentation now enable the study of microstructure property relationships, material intrinsic behaviour including orientation-dependence and plasticity, racture dynamics, or the performance of novel micro-3D-printed metamaterials, to name but a few.

Thanks to its versatility, in situ SEM-based micromechanics is contributing to numerous scientific domains, including thin films and coatings, metallurgy, glasses and ceramics, semiconductors, biomechanics, or architectured materials. Performing micromechanical tests in situ in a SEM offers two important advantages: (1) unmatched control, stability, and positioning accuracy,and (2) the possibility to perform unique correlative experiments based on, for example, the combination of mechanical data with direct imaging or EBSD measurements.

An increasingly important branch of micromechanical testing can be found in the simulation of real-world, extreme operation conditions, such as high temperatures in engines, cryogenic temperatures in hydrogen storage, dynamic loading under shock or impact, high frequency cyclic fatigue, or a combination thereof. Progress in the understanding of material behaviour at such conditions is clearly linked to the availability of laboratory equipment that can perform reliable tests under such conditions.

We present the most recent developments in instrumentation for in situ extreme mechanics testing at themicro and nanoscales. In focusisa testing platform capable of strainrate dependent testing over the range from 0.0001 s^-1 up to 10’000 s^-1  (8 orders of magnitude) with simultaneoushigh-speed actuation and sensing capabilities with nanometer and micronewton resolution, respectively. Furthermore, the challenges and solutions to performing extreme micromechanics over the temperature range from -150°C to 1000°C, and the inherent advantages of using small volumes of sample material will be discussed. Finally, we present examples of such extreme micromechanical in situ tests and discuss future research directions in the field of extreme micromechanics.

New correlative methods of in-situ micromechanical testing will be presented, including the combination of the Alemnis ASA with the Nenovision AFM and Imina electrical nanoprobing systems.

个人简介：

Viola Paul earned an M.Sc. in Materials Engineering from the University of Technology Malaysia, followed by a Ph.D. in Materials Science from Kyushu University, Japan. After completing her Ph.D., she spent 2.5 years as a postdoctoral researcher at NIMS in the Mechanical Properties Group, led by Prof. Takahito Ohmura, where she specialized in nanomechanical testing of metals under extreme conditions, with a focus on high-temperature. She later joined Alemnis AG, where she is passionate about developing novel applications for nano- and micromechanical testing, pushing the limits of nanoindentation capabilities, and expanding its applications in various research fields.