Discontinuous strain-induced martensite transformation related to the Portevin-Le Chatelier effect in a medium manganese steel

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

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 ...

Effect of Heat Treatment on the Portevin-Le Chatelier Effect of Al-2.5%Mg Alloy

An experimental study is presented on the effect of microstructural change on the Portevin-Le Chatelier effect behaviour of Al-2.5%Mg alloy. Tensile tests are performed on the as received and heat treated (at 400 oC for 16 hours) samples for a wide range of strain rates. The serrations observed in the stress-time curve are investigated from statistical analysis point of view. Microstructures of...

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.