We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
On the propensity to adiabatic shear, localized instability or microcracking onset
Summary
This study examined how microscale adiabatic shear, flow localization, and microcracking initiate in single and polycrystalline metals, finding that local dynamic effects control microplastic behavior even under globally quasi-static loading. The results show that early micro-band formation can signal the onset of larger-scale instabilities.
The current study objectives to develop aspects in materials characterized by progressive softening assisted by quasi-adiabatic effects. A fine scale phenomenological approach was followed, demonstrated by single and polycrystalline materials with high and low crystal structures symmetry. Even under global quasi-static conditions, local dynamic effects control the microplastic features. This was investigated in the case of alternating ductile/brittle micro events in cubic crystals and in polycrystals characterized by slip/twinning deformation mechanisms. It was found that the propensity to inhomogeneous deformation or micro-band formation might indicate the early stages of macro-band triggering. The enhancement of flow localization, is originated by dislocation group dynamics or by a sudden singular stress field release due to microcrack formation.