Abstract
Metallic single crystals of hcp (Zn and Cd) and fcc (Cu) lattice structure with various crystallographic orientation were deformed in tension at room temperature. For the study of the intermittent, scale-invariant character of collective dislocation dynamics (crackling plasticity), initially discovered in ice samples, the acoustic emission technique was used. The AE event energy distributions always follow the power law given by P(E) ∼E - τ E . The exponent τ E. was calculated for all single crystals and its value is discussed with respect to a character of plastic deformation (single or multi-slip, hardening, twinning).

Key words
acoustic emission, plastic deformation, dislocation dynamics, self-organization and patterning

Full text (138 KB)