In a recent publication, Hawes and Bale provide an extended discussion of phenotypic plasticity in the context of low temperature responses of animals. They argue that phenotypic plasticity may be partitioned phylogenetically at several levels and go on to explore these levels, and cold hardiness strategies that they term cryotypes, which in their view constitute cryotypic plasticity. Here we a...

Ti–6Al–4V foams are produced by the expansion of pressurized argon pores trapped in billets created by powder metallurgy. Pore expansion during thermal cycling (840–1030 C, which induces transformation superplasticity in Ti–6Al–4V) improves both the foaming rate (by reducing the flow stress) and the final porosity (by delaying fracture of the pores and subsequent escape of the gas), as compared...

Experiments were conducted on a magnesium AZ31 alloy to evaluate the role of cavitation in high temperature superplasticity. Samples were processed by equal-channel angular pressing (ECAP) and then pulled to failure in tension at a temperature of 623K. Similar tests were also conducted on the as-received alloy. The results show the development of significant internal cavitation in this alloy wh...

There has been considerable success over the past five decades in developing a phenomenological and micromechanism-based understanding of lastic flow, creep and superplasticity. Although it is widely known that grain sizes have a distribution in polycrystals and nanocrystals, this factor s usually not included in most analysis of deformation and failure. Experimental observations relating to th...

We introduce a continuous damage fiber bundle model and compare its behavior with that of dry fiber bundles. Several interesting constitutive behaviors, such as plasticity, are found in this model depending on the value of the damage parameter and on the form of the disorder distribution. We compare the constitutive behavior of global load transfer models, obtained analytically, with local load...