Relaxation oscillations and negative strain rate sensitivity in the Portevin - Le Chatelier effect

Details Relaxation oscillations and negative strain rate sensitivity in the Portevin - Le Chatelier effect Relaxation oscillations and negative strain rate sensitivity in the Portevin - Le Chatelier effect

2000-01-06

arxiv.org/abs/nlin/0001008v1

Nonlinear Sciences

Chaotic Dynamics

7 figures, To appear in Phys. Rev. E

Scientific paper

10.1103/PhysRevE.61.3664

A characteristic feature of the Portevin - Le Chatelier effect or the jerky flow is the stick-slip nature of stress-strain curves which is believed to result from the negative strain rate dependence of the flow stress. The latter is assumed to result from the competition of a few relevant time scales controlling the dynamics of jerky flow. We address the issue of time scales and its connection to the negative strain rate sensitivity of the flow stress within the framework of a model for the jerky flow which is known to reproduce several experimentally observed features including the negative strain rate sensitivity of the flow stress. We attempt to understand the above issues by analyzing the geometry of the slow manifold underlying the relaxational oscillations in the model. We show that the nature of the relaxational oscillations is a result of the atypical bent geometry of the slow manifold. The analysis of the slow manifold structure helps us to understand the time scales operating in different regions of the slow manifold. Using this information we are able to establish connection with the strain rate sensitivity of the flow stress. The analysis also helps us to provide a proper dynamical interpretation for the negative branch of the strain rate sensitivity.

Affiliated with

Also associated with

No associations

Rating

Relaxation oscillations and negative strain rate sensitivity in the Portevin - Le Chatelier effect does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Relaxation oscillations and negative strain rate sensitivity in the Portevin - Le Chatelier effect, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Relaxation oscillations and negative strain rate sensitivity in the Portevin - Le Chatelier effect will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-670597