MICROSCOPY AND MICROINDENTATION MECHANICS OF SINGLE-CRYSTAL FE-3 WT-PERCENT-SI .1. ATOMIC-FORCE MICROSCOPY OF A SMALL INDENTATION

Atomic force microscope measurements of elastic-plastic indentation in to an Fe-3 wt. % Si single crystal showed that the volume displaced to the surface is nearly equal to the volume of the cavity. The surface displacement profiles and plastic zone size caused by a 69 nm penetrat ion of a Vickers diamond tip are reasonably represented by an elastic- plastic continuum model. Invoking conservation of volume, estimates of the number of dislocations emanating from the free surface are reason ably consistent with the number of dislocations that have formed in th e plastic zone to represent an average calculated plastic strain of 0. 044.