Nanomechanical testing at high strain rates: New instrumentation for nanoindentation and microcompression

Publication date: 15 June 2018
Source:Materials & Design, Volume 148
Author(s): Gaylord Guillonneau, Maxime Mieszala, Juri Wehrs, Jakob Schwiedrzik, Serge Grop, Damian Frey, Laetitia Philippe, Jean-Marc Breguet, Johann Michler, Jeffrey M. Wheeler
Micromechanical testing is normally limited to the quasi-static strain rate regime: 10⁻⁵ to 10⁻²s⁻¹. In this work, a nanomechanical testing device has been developed that allows indentation and microcompression at strain rates from the quasi-static regime continuously up to the high strain rate regime. To reach the highest strain rates, the conventional, strain gage-based load cell was replaced with a new piezo-based sensor. The sensor's concept, calibration methods, and measurement strategies are detailed. It is shown, using nanocrystalline Nickel as a case study material, that this new high strain rate device can measure precisely mechanical properties at strain rates up to 1000s⁻¹ by nanoindentation, and strain rates up to 100s⁻¹ by microcompression, enabling the device to measure strain rates over 9 orders of magnitude.

Graphical abstract

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