Quantitative In-Situ TEM Nanoindentation Apparatus

75333-Nano-indentation is the primary technique for assessing the nanomechanical behavior of small volumes of materials. With this technique the load required to produce a given displacement into the sample by a sharp diamond tip is measured, and the hardness of the material is derived. However, the microstructural behavior that causes the mechanical response of the material is not often readily apparent. This project will develop a new nano-indentation machine for operation inside a transmission electron microscope, yielding quantitative load-displacement data concomitant with real time images of the microstructural behavior. To accomplish this objective, a miniature force-displacement transducer, capable of electrostatic actuation and capacitive displacement sensing, will be integrated into an in situ transmission-electron-microscopy (TEM) nanoindentation holder equipped with a three-axis course positioner and a three-axis piezoelectric positioner. Phase I will develop a nano-indentation device consisting of a force-displacement transducer, a piezoelectric positioner, and control hardware and software. The fully-integrated apparatus will then be tested in a transmission electron microscope. Commercial Applications and Other Benefits as described by the awardee: In situ TEM nanoindentation should substantially improve our ability to engineer the mechanical behavior of materials through altering microstructural characteristics, thereby increasing the lifetime of components and products used in day-to-day life.