Photograph of the setup: ❶ preparation chamber; ❷ 1200 K oven; ❸ ion gun; ❹ LEED-Auger; ❺ mechanical test chamber; ❻ video camera; ❼ long focus optical instrument; ❽ STM tip preparation stage; and ❾ external motors.
Technical drawing of the internal compression setup (a) overview including the external motors and the UHV chamber: ❶ rotary feedthrough; ❷ sample localization; ❸ AFM/STM stage also used as mechanical structure for the internal compression device; and ❹ UHV chamber. (b) Technical drawing of various elements composing the compression setup: ❺ piezoelectric actuators; ❻ mechanical guides; ❼ optical position sensors; ❽ load cells; ❾ sample holder; and ❿ conical stressors (compression plates) acting as thermal barriers. (c) Technical drawing of the sample holder. The sample is scanned by AFM/STM tips on its lower part.
Stress/strain curve obtained on a Ni3(Al,Ta) single crystal for compression at 300 K along the [ ] axis. First straining carried out by external motors (blue filled triangles) and second straining using the internal piezoelectric actuators (green open squares). The stress change (7.9 MPa in this case) induced by the declutch is about 6%. Some oscillations are visible during plastic deformation: they are due to sample relaxation while taking several AFM images at different strain values.
Au(111) surface obtained by STM investigations at 300 K and at different straining (a) 4.25 MPa, and (b) 4.40 MPa. Grey arrows indicate the stress-induced modifications of some nanometer scale steps. The profile is associated with the grey dashed line.
Herringbone patterns on Au(111) surface obtained by STM investigations at 300 K and at different straining (a) 4.25 MPa, and (b) 4.40 MPa. The profile is associated with the grey dashed line.
STM image of Au(111) surface at 90 K under an applied stress of 1.70 MPa. Two slip lines are indicated by dashed arrows. (b) is a blow-up of a large terrace shown in (a).
AFM images of the evolution of Ni3(Al,Ta) surface at increasing plastic strain deformed at 600 K along the [ ] axis (fixed point indicated by a circle). (a) ɛp = 0.15%, (b) ɛp = 0.25%, (c) ɛp = 0.50%, and (d) profile extracted from the slip line labelled X in (c). Some cube cross slips are shown by arrows on (b).
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