Repeated yield drop phenomena as a cooperative effect

Ananthakrishna, G. (1984) Repeated yield drop phenomena as a cooperative effect Bulletin of Materials Science, 6 (4). pp. 665-676. ISSN 0250-4707

PDF - Publisher Version

Official URL:

Related URL:


We present a theoretical model of repeated yielding (RY) which reproduces many experimentally observed features, apart from showing how the temporal behaviour of the phenomenon emerges as a consequence of the cooperative behaviour of defects. We first consider the case of step-like creep curves. Our model leads to a coupled set of nonlinear differential equations which admit limit cycle solutions, and thence jumps on the creep curve. Approximate closed form solutions for the limit cycles and the steps on the creep curve are obtained. The model is then extended to the constant strain rate experiment by including the machine equation. The temporal ordering of RY is shown to follow, as well as several other features characteristic of RY. Chaotic flow is also exhibited: the model has a sequence of period-doubling bifurcations with an exponent equal to that of the quadratic map. Finally, we have analysed the fluctuations during the onset of RY using nonlinear Langevin equations. Fluctuations in the periodic (RY) phase are also investigated. We conclude that RY is another example of a dissipative structure.

Item Type:Article
Source:Copyright of this article belongs to Indian Academy of Sciences.
Keywords:Repeated Yield Drop; Defects; Cooperative Behaviour; Limit Cycle Solutions; Nonlinear Langevin Equations
ID Code:550
Deposited On:21 Sep 2010 11:45
Last Modified:16 May 2016 11:45

Repository Staff Only: item control page