By means of an ultrafast opto-acoustic technique we study the nanoindentation of thin chromium films on sapphire substrates by a ceramic ball bearing. Acoustic echoes at similar to 40 GHz returning from the film-indenter interface allow the film indentation profiles to be probed to sub-nanometer resolution over contact areas similar to 25 mu upsilon m in radius. The deformation of the films during loading is thereby revealed. Furthermore, thermal wave imaging of the contact at megahertz frequencies is simultaneously achieved.
Picosecond time scale imaging of mechanical contacts / Thomas, Dehoux; Oliver B., Wright; LI VOTI, Roberto. - In: PHYSICS PROCEDIA. - ISSN 1875-3892. - STAMPA. - 3:1(2010), pp. 351-356. (Intervento presentato al convegno International Congress on Ultrasonics tenutosi a Santiago, CHILE nel JAN 11-17, 2009) [10.1016/j.phpro.2010.01.046].
Picosecond time scale imaging of mechanical contacts
LI VOTI, Roberto
2010
Abstract
By means of an ultrafast opto-acoustic technique we study the nanoindentation of thin chromium films on sapphire substrates by a ceramic ball bearing. Acoustic echoes at similar to 40 GHz returning from the film-indenter interface allow the film indentation profiles to be probed to sub-nanometer resolution over contact areas similar to 25 mu upsilon m in radius. The deformation of the films during loading is thereby revealed. Furthermore, thermal wave imaging of the contact at megahertz frequencies is simultaneously achieved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
