Evaluation of Mechanical Properties and Microstructures of Multi-Walled Carbon Nanotube/Alumina Composites Prepared by Pressureless Sintering
Published: 1 January 2013
TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series A , Volume 79, pp 764-768; https://doi.org/10.1299/kikaia.79.764
Abstract: Alumina ceramics reinforced with multi-walled carbon nanotubes (MWCNTs) have been prepared by pressureless sintering. Resultant composites with the MWCNT contents up to 0.9 vol.% have shown relative density as high as 98%. In addition, with increasing the MWCNT contents up to 0.9 vol.%, bending strength and fracture toughness of the composites is found to be increase gradually, and the composite containing 0.9 vol.% MWCNTs have shown 18% and 32% simultaneous increases in bending strength (699.1 ± 46.1 MPa) and fracture toughness (5.33 ± 0.03 MPa·m1/2), respectively, compared with MWCNT-free alumina. Observations on the fracture surface and the tensile-loading experiments of MWCNTs using an in-situ SEM method with a nanomanipulator system demonstrate that the MWCNTs, rather than pulling out from the alumina matrix, tend to fail in so-called “clean break” manner. Theoretical calculations imply that tougher ceramics with MWCNT can be obtained by creating the appropriate interaction between the matrix and MWCNT: not too week but also not too strong to permit an adequate load transfer between the two parts and thus a consequent pulling out without breakage of MWCNT. For the design of tougher ceramics with MWCNTs, appropriate modification of fiber/matrix interface will be one of important factors.
Keywords: toughness / carbon nanotubes / fracture / MWCNT / Pressureless / matrix / bending / MPa / sintering / vol
Scifeed alert for new publicationsNever miss any articles matching your research from any publisher
- Get alerts for new papers matching your research
- Find out the new papers from selected authors
- Updated daily for 49'000+ journals and 6000+ publishers
- Define your Scifeed now
Click here to see the statistics on "TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series A" .