Ultrafine-grained (UFG) aluminum and UFG composite containing carbon nanotubes (CNTs) are fabricated by hot-rolling the ball-milled powder, and their mechanical properties are investigated at warm temperatures ranging from 423 to 523. K. A number of voids are formed at the non-equilibrium grain boundaries in the UFG aluminum during tensile deformation at warm temperatures, resulting in poor ductility. However, the UFG composite exhibits enhanced ductility as well as superior yield stress. CNTs suppress the development of non-equilibrium grain boundaries and the formation of voids, giving rise to notably enhanced ductility at warm temperatures.
Bibliographical noteFunding Information:
This research was supported by the Korea Science and Engineering Foundation Grant (No. 2010-0016139 ) and the Second Stage of Brain Korea 21 Project in 2010.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering