2016/04/06 by Ádám István Hegyi, Hegyi, Ádám István, Péter Dusán Ispánovity +14
Engineering · Physics and Astronomy · #Advanced Surface Polishing Techniques #FOS: Physical sciences #Force Microscopy Techniques and Applications #Materials Science (cond-mat.mtrl-sci) #Metal and Thin Film Mechanics
paper · pdf · doi:10.48550/arxiv.1604.01815
openalex publication_date 2016/04/06 · openalex created_date 2022/10/06 · openalex updated_date 2026/07/28
Plastic deformation of micron-scale crystalline materials differ considerably\nfrom bulk ones, because it is characterized by random strain bursts. To obtain\na detailed picture about this stochastic phenomenon, micron sized pillars have\nbeen fabricated and compressed in the chamber of a SEM. An improved FIB\nfabrication method is proposed to get non-tapered micro-pillars with a maximum\ncontrol over their shape. The in-situ compression device developed allows high\naccuracy sample positioning and force/displacement measurements with high data\nsampling rate. The collective avalanche-like motion of dislocations appears as\nstress drops on the stress-strain curve. To confirm that these stress drops are\ndirectly related to dislocation activity, and not to some other effect, an\nacoustic emission transducer has been mounted under the sample to record\nemitted acoustic activity during strain-controlled compression tests of Al-5 %\nMg micro-pillars. The correlation between the stress drops and the acoustic\nemission signals indicates that indeed dislocation avalanches are responsible\nfor the stochastic character of the deformation process.\n