Ensayo Le Chatelier-Anstett

Portevin-Le chatelier effect

Aluminum subjected to smooth mechanical loading does not often deform in a correspondingly smooth manner. Typically it deforms inhomogeneously through the propagation of deformation fronts that slowly traverse the sample. These are called Portevin-Le Chatelier fronts; what determines their velocity has been somewhat mysterious. We present a phenomenological theory for deformation fronts that ce...

Portevin–Le Chatelier effect in an aluminum alloy

The Le Chatelier Principle in Data Envelopment Analysis

The paper gives a brief review of the nonparametric approach to efficiency measurement or Data Envelopment Analysis as it is known in the operations research literature. Inequalities are derived between the efficiency measures when different assumptions are made on the technology sets or on the behavior of managers. Of particular interest is the derivation of a Le Chatelier Principle for measur...

Chaotic and power law states in the Portevin - Le Chatelier effect

– Recent studies on the Portevin Le Chatelier effect report an intriguing crossover phenomenon from a low dimensional chaotic to an infinite dimensional scale invariant power law regime in experiments on CuAl single crystals and AlMg polycrystals, as a function of strain rate. We devise a fully dynamical model which reproduces these results. At low and medium strain rates, the model is chaotic ...

Time-resolved strain mapping measurements of individual Portevin–Le Chatelier deformation bands

A technique based on high-speed digital photography and image correlation for direct whole-field strain mapping of Portevin–Le Chatelier deformation bands is described. Results for a type B band show that the deformation band was formed within a few milliseconds and remained stationary as no motion of the band was detected. 2005 Published by Elsevier Ltd. on behalf of Acta Materialia Inc.