Force Measurement

Nanoindentation

Various nanoindentor tools are available on the market for the characterization of the mechanical and tribological properties of materials, such as hardness and Young's modulus. The interpretation of nanoindentation measurements usually requires expensive AFM or TEM equipment. An economical alternative is to bring nanoindentation to the SEM.

The unique combination of precision manipulation and controlled nanomechanical testing in SEM or FIB is possible by fitting a force sensor to a precise and stable micromanipulator or by mounting the sample to a force transducer and indenting the sample using a suitable tool tip. These alternatives make it possible to simultaneously observe and quantify the mechanical behaviour of nanoscale volumes of solids in a few quick and easy steps.

Tensile measurement

Existing devices for nanomechanical testing have either the necessary spatial or the necessary force resolution, but they rarely have both. Conventional AFM and nanoindentation-based systems are not usually suitable for in-situ testing. Micro-electro-mechanical systems (MEMS) usually only allow small displacements and conventional in-situ test rigs have insufficient displacement and force resolution. Another restriction of most systems is that they usually operate only in one predefined plane.

The MM3A-EM micromanipulator fitted with the FMS-EM plug-in tool can be used to overcome these limitations. Forces can be measured in a large working area in three planes of movement using a highly sensitive piezoresistive AFM tip.

Substages with positional encoders are also an ideal tool for applications of this nature. They can be fitted with a force sensor, allowing measurements in two planes with direct positional feedback.

Nanoforging

Nanoforging refers to the production of different types of nano-structured materials from metallic alloys. The process first establishes nano-structures in the bulk alloy and then separates them by selective phase dissolution. These objects are then isolated from the sample surface in SEM using manipulators and placed on a micro-anvil. Finally, an in-situ nanomechanical test is performed, in which the shape of the object is changed by nanoforging using a micro-hammer. In this way free-standing, high-strength, metallic nano-objects with dimensions in the 100 nm range can be created.