a1 Department of Materials Physics, Eötvös University Budapest, 1117 Budapest, Pázmany P. sétány 1/A, Hungary
a2 Departments of Aerospace & Mechanical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089-1453; Materials Research Group, School of Engineering Sciences, University of Southampton, Southampton SO17 1BJ, UK
Spatial fluctuations of the microstructure suggest possible self-organized criticality in the Portevin–Le Chatelier plastic instability occurring in age-hardenable alloys. The discontinuous yielding found in a supersaturated Al alloy can be characterized by a universal power-law spectrum that is independent of the experimental conditions. The result provides an explanation for the formation of unexpected detrimental strain localizations when samples are severely deformed, giving a framework for studying the simultaneous effects of solute atoms and precipitates in the decomposition of solid solutions.
(Received September 03 2011)
(Accepted December 15 2011)