A Ni-8Zr high strength ultrafine eutectic-dendrite composite with large plasticity has been developed in the Ni-Zr binary eutectic system. The excellent mechanical properties are attributed to the specific heterogeneous microstructure with distinctly different length scales, i.e., micrometer-size ductile dendrites combined with an ultrafine eutectic matrix. The plastic deformation mainly proceeds through a shear banding mechanism. However, there is no significant shear localization due to the constraint effect of ductile solid solution Ni phases including dendrites and/or alternating lamellar layers. Furthermore, excessive shear stress and accumulated shear strain can be effectively released and accommodated by delocalization and multiplication of shear bands.
Bibliographical noteFunding Information:
The authors are grateful to M. H. Lee and E. Fleury for valuable discussions. This work was supported by the Global Research Laboratory Program of the Korea Ministry of Education, Science and Technology. J. M. Park, T. E. Kim, and S. W. Sohn acknowledge the support from the Third Stage of Brain Korea 21 Project in 2008.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)